wapshop/node_modules/vue-template-compiler/build.js

'use strict';

Object.defineProperty(exports, '__esModule', { value: true });

function _interopDefault (ex) { return (ex && (typeof ex === 'object') && 'default' in ex) ? ex['default'] : ex; }

var deindent = _interopDefault(require('de-indent'));
var he = require('he');

/*  */

/**
 * Convert a value to a string that is actually rendered.
 */
function _toString (val) {
  return val == null
    ? ''
    : typeof val === 'object'
      ? JSON.stringify(val, null, 2)
      : String(val)
}

/**
 * Convert a input value to a number for persistence.
 * If the conversion fails, return original string.
 */
function toNumber (val) {
  var n = parseFloat(val);
  return isNaN(n) ? val : n
}

/**
 * Make a map and return a function for checking if a key
 * is in that map.
 */
function makeMap (
  str,
  expectsLowerCase
) {
  var map = Object.create(null);
  var list = str.split(',');
  for (var i = 0; i < list.length; i++) {
    map[list[i]] = true;
  }
  return expectsLowerCase
    ? function (val) { return map[val.toLowerCase()]; }
    : function (val) { return map[val]; }
}

/**
 * Check if a tag is a built-in tag.
 */
var isBuiltInTag = makeMap('slot,component', true);

/**
 * Remove an item from an array
 */
function remove (arr, item) {
  if (arr.length) {
    var index = arr.indexOf(item);
    if (index > -1) {
      return arr.splice(index, 1)
    }
  }
}

/**
 * Check whether the object has the property.
 */
var hasOwnProperty = Object.prototype.hasOwnProperty;
function hasOwn (obj, key) {
  return hasOwnProperty.call(obj, key)
}

/**
 * Check if value is primitive
 */
function isPrimitive (value) {
  return typeof value === 'string' || typeof value === 'number'
}

/**
 * Create a cached version of a pure function.
 */
function cached (fn) {
  var cache = Object.create(null);
  return (function cachedFn (str) {
    var hit = cache[str];
    return hit || (cache[str] = fn(str))
  })
}

/**
 * Camelize a hyphen-delimited string.
 */
var camelizeRE = /-(\w)/g;
var camelize = cached(function (str) {
  return str.replace(camelizeRE, function (_, c) { return c ? c.toUpperCase() : ''; })
});

/**
 * Capitalize a string.
 */
var capitalize = cached(function (str) {
  return str.charAt(0).toUpperCase() + str.slice(1)
});

/**
 * Hyphenate a camelCase string.
 */
var hyphenateRE = /([^-])([A-Z])/g;
var hyphenate = cached(function (str) {
  return str
    .replace(hyphenateRE, '$1-$2')
    .replace(hyphenateRE, '$1-$2')
    .toLowerCase()
});

/**
 * Simple bind, faster than native
 */
function bind (fn, ctx) {
  function boundFn (a) {
    var l = arguments.length;
    return l
      ? l > 1
        ? fn.apply(ctx, arguments)
        : fn.call(ctx, a)
      : fn.call(ctx)
  }
  // record original fn length
  boundFn._length = fn.length;
  return boundFn
}

/**
 * Convert an Array-like object to a real Array.
 */
function toArray (list, start) {
  start = start || 0;
  var i = list.length - start;
  var ret = new Array(i);
  while (i--) {
    ret[i] = list[i + start];
  }
  return ret
}

/**
 * Mix properties into target object.
 */
function extend (to, _from) {
  for (var key in _from) {
    to[key] = _from[key];
  }
  return to
}

/**
 * Quick object check - this is primarily used to tell
 * Objects from primitive values when we know the value
 * is a JSON-compliant type.
 */
function isObject (obj) {
  return obj !== null && typeof obj === 'object'
}

/**
 * Strict object type check. Only returns true
 * for plain JavaScript objects.
 */
var toString = Object.prototype.toString;
var OBJECT_STRING = '[object Object]';
function isPlainObject (obj) {
  return toString.call(obj) === OBJECT_STRING
}

/**
 * Merge an Array of Objects into a single Object.
 */
function toObject (arr) {
  var res = {};
  for (var i = 0; i < arr.length; i++) {
    if (arr[i]) {
      extend(res, arr[i]);
    }
  }
  return res
}

/**
 * Perform no operation.
 */
function noop () {}

/**
 * Always return false.
 */
var no = function () { return false; };

/**
 * Return same value
 */
var identity = function (_) { return _; };

/**
 * Generate a static keys string from compiler modules.
 */
function genStaticKeys (modules) {
  return modules.reduce(function (keys, m) {
    return keys.concat(m.staticKeys || [])
  }, []).join(',')
}

/**
 * Check if two values are loosely equal - that is,
 * if they are plain objects, do they have the same shape?
 */
function looseEqual (a, b) {
  var isObjectA = isObject(a);
  var isObjectB = isObject(b);
  if (isObjectA && isObjectB) {
    try {
      return JSON.stringify(a) === JSON.stringify(b)
    } catch (e) {
      // possible circular reference
      return a === b
    }
  } else if (!isObjectA && !isObjectB) {
    return String(a) === String(b)
  } else {
    return false
  }
}

function looseIndexOf (arr, val) {
  for (var i = 0; i < arr.length; i++) {
    if (looseEqual(arr[i], val)) { return i }
  }
  return -1
}

/**
 * Ensure a function is called only once.
 */

/*  */

var isUnaryTag = makeMap(
  'area,base,br,col,embed,frame,hr,img,input,isindex,keygen,' +
  'link,meta,param,source,track,wbr'
);

// Elements that you can, intentionally, leave open
// (and which close themselves)
var canBeLeftOpenTag = makeMap(
  'colgroup,dd,dt,li,options,p,td,tfoot,th,thead,tr,source'
);

// HTML5 tags https://html.spec.whatwg.org/multipage/indices.html#elements-3
// Phrasing Content https://html.spec.whatwg.org/multipage/dom.html#phrasing-content
var isNonPhrasingTag = makeMap(
  'address,article,aside,base,blockquote,body,caption,col,colgroup,dd,' +
  'details,dialog,div,dl,dt,fieldset,figcaption,figure,footer,form,' +
  'h1,h2,h3,h4,h5,h6,head,header,hgroup,hr,html,legend,li,menuitem,meta,' +
  'optgroup,option,param,rp,rt,source,style,summary,tbody,td,tfoot,th,thead,' +
  'title,tr,track'
);

/**
 * Not type-checking this file because it's mostly vendor code.
 */

/*!
 * HTML Parser By John Resig (ejohn.org)
 * Modified by Juriy "kangax" Zaytsev
 * Original code by Erik Arvidsson, Mozilla Public License
 * http://erik.eae.net/simplehtmlparser/simplehtmlparser.js
 */

// Regular Expressions for parsing tags and attributes
var singleAttrIdentifier = /([^\s"'<>/=]+)/;
var singleAttrAssign = /(?:=)/;
var singleAttrValues = [
  // attr value double quotes
  /"([^"]*)"+/.source,
  // attr value, single quotes
  /'([^']*)'+/.source,
  // attr value, no quotes
  /([^\s"'=<>`]+)/.source
];
var attribute = new RegExp(
  '^\\s*' + singleAttrIdentifier.source +
  '(?:\\s*(' + singleAttrAssign.source + ')' +
  '\\s*(?:' + singleAttrValues.join('|') + '))?'
);

// could use https://www.w3.org/TR/1999/REC-xml-names-19990114/#NT-QName
// but for Vue templates we can enforce a simple charset
var ncname = '[a-zA-Z_][\\w\\-\\.]*';
var qnameCapture = '((?:' + ncname + '\\:)?' + ncname + ')';
var startTagOpen = new RegExp('^<' + qnameCapture);
var startTagClose = /^\s*(\/?)>/;
var endTag = new RegExp('^<\\/' + qnameCapture + '[^>]*>');
var doctype = /^<!DOCTYPE [^>]+>/i;
var comment = /^<!--/;
var conditionalComment = /^<!\[/;

var IS_REGEX_CAPTURING_BROKEN = false;
'x'.replace(/x(.)?/g, function (m, g) {
  IS_REGEX_CAPTURING_BROKEN = g === '';
});

// Special Elements (can contain anything)
var isPlainTextElement = makeMap('script,style,textarea', true);
var reCache = {};

var decodingMap = {
  '&lt;': '<',
  '&gt;': '>',
  '&quot;': '"',
  '&amp;': '&',
  '&#10;': '\n'
};
var encodedAttr = /&(?:lt|gt|quot|amp);/g;
var encodedAttrWithNewLines = /&(?:lt|gt|quot|amp|#10);/g;

function decodeAttr (value, shouldDecodeNewlines) {
  var re = shouldDecodeNewlines ? encodedAttrWithNewLines : encodedAttr;
  return value.replace(re, function (match) { return decodingMap[match]; })
}

function parseHTML (html, options) {
  var stack = [];
  var expectHTML = options.expectHTML;
  var isUnaryTag$$1 = options.isUnaryTag || no;
  var canBeLeftOpenTag$$1 = options.canBeLeftOpenTag || no;
  var index = 0;
  var last, lastTag;
  while (html) {
    last = html;
    // Make sure we're not in a plaintext content element like script/style
    if (!lastTag || !isPlainTextElement(lastTag)) {
      var textEnd = html.indexOf('<');
      if (textEnd === 0) {
        // Comment:
        if (comment.test(html)) {
          var commentEnd = html.indexOf('-->');

          if (commentEnd >= 0) {
            advance(commentEnd + 3);
            continue
          }
        }

        // http://en.wikipedia.org/wiki/Conditional_comment#Downlevel-revealed_conditional_comment
        if (conditionalComment.test(html)) {
          var conditionalEnd = html.indexOf(']>');

          if (conditionalEnd >= 0) {
            advance(conditionalEnd + 2);
            continue
          }
        }

        // Doctype:
        var doctypeMatch = html.match(doctype);
        if (doctypeMatch) {
          advance(doctypeMatch[0].length);
          continue
        }

        // End tag:
        var endTagMatch = html.match(endTag);
        if (endTagMatch) {
          var curIndex = index;
          advance(endTagMatch[0].length);
          parseEndTag(endTagMatch[1], curIndex, index);
          continue
        }

        // Start tag:
        var startTagMatch = parseStartTag();
        if (startTagMatch) {
          handleStartTag(startTagMatch);
          continue
        }
      }

      var text = (void 0), rest$1 = (void 0), next = (void 0);
      if (textEnd >= 0) {
        rest$1 = html.slice(textEnd);
        while (
          !endTag.test(rest$1) &&
          !startTagOpen.test(rest$1) &&
          !comment.test(rest$1) &&
          !conditionalComment.test(rest$1)
        ) {
          // < in plain text, be forgiving and treat it as text
          next = rest$1.indexOf('<', 1);
          if (next < 0) { break }
          textEnd += next;
          rest$1 = html.slice(textEnd);
        }
        text = html.substring(0, textEnd);
        advance(textEnd);
      }

      if (textEnd < 0) {
        text = html;
        html = '';
      }

      if (options.chars && text) {
        options.chars(text);
      }
    } else {
      var stackedTag = lastTag.toLowerCase();
      var reStackedTag = reCache[stackedTag] || (reCache[stackedTag] = new RegExp('([\\s\\S]*?)(</' + stackedTag + '[^>]*>)', 'i'));
      var endTagLength = 0;
      var rest = html.replace(reStackedTag, function (all, text, endTag) {
        endTagLength = endTag.length;
        if (!isPlainTextElement(stackedTag) && stackedTag !== 'noscript') {
          text = text
            .replace(/<!--([\s\S]*?)-->/g, '$1')
            .replace(/<!\[CDATA\[([\s\S]*?)]]>/g, '$1');
        }
        if (options.chars) {
          options.chars(text);
        }
        return ''
      });
      index += html.length - rest.length;
      html = rest;
      parseEndTag(stackedTag, index - endTagLength, index);
    }

    if (html === last) {
      options.chars && options.chars(html);
      if (process.env.NODE_ENV !== 'production' && !stack.length && options.warn) {
        options.warn(("Mal-formatted tag at end of template: \"" + html + "\""));
      }
      break
    }
  }

  // Clean up any remaining tags
  parseEndTag();

  function advance (n) {
    index += n;
    html = html.substring(n);
  }

  function parseStartTag () {
    var start = html.match(startTagOpen);
    if (start) {
      var match = {
        tagName: start[1],
        attrs: [],
        start: index
      };
      advance(start[0].length);
      var end, attr;
      while (!(end = html.match(startTagClose)) && (attr = html.match(attribute))) {
        advance(attr[0].length);
        match.attrs.push(attr);
      }
      if (end) {
        match.unarySlash = end[1];
        advance(end[0].length);
        match.end = index;
        return match
      }
    }
  }

  function handleStartTag (match) {
    var tagName = match.tagName;
    var unarySlash = match.unarySlash;

    if (expectHTML) {
      if (lastTag === 'p' && isNonPhrasingTag(tagName)) {
        parseEndTag(lastTag);
      }
      if (canBeLeftOpenTag$$1(tagName) && lastTag === tagName) {
        parseEndTag(tagName);
      }
    }

    var unary = isUnaryTag$$1(tagName) || tagName === 'html' && lastTag === 'head' || !!unarySlash;

    var l = match.attrs.length;
    var attrs = new Array(l);
    for (var i = 0; i < l; i++) {
      var args = match.attrs[i];
      // hackish work around FF bug https://bugzilla.mozilla.org/show_bug.cgi?id=369778
      if (IS_REGEX_CAPTURING_BROKEN && args[0].indexOf('""') === -1) {
        if (args[3] === '') { delete args[3]; }
        if (args[4] === '') { delete args[4]; }
        if (args[5] === '') { delete args[5]; }
      }
      var value = args[3] || args[4] || args[5] || '';
      attrs[i] = {
        name: args[1],
        value: decodeAttr(
          value,
          options.shouldDecodeNewlines
        )
      };
    }

    if (!unary) {
      stack.push({ tag: tagName, lowerCasedTag: tagName.toLowerCase(), attrs: attrs });
      lastTag = tagName;
    }

    if (options.start) {
      options.start(tagName, attrs, unary, match.start, match.end);
    }
  }

  function parseEndTag (tagName, start, end) {
    var pos, lowerCasedTagName;
    if (start == null) { start = index; }
    if (end == null) { end = index; }

    if (tagName) {
      lowerCasedTagName = tagName.toLowerCase();
    }

    // Find the closest opened tag of the same type
    if (tagName) {
      for (pos = stack.length - 1; pos >= 0; pos--) {
        if (stack[pos].lowerCasedTag === lowerCasedTagName) {
          break
        }
      }
    } else {
      // If no tag name is provided, clean shop
      pos = 0;
    }

    if (pos >= 0) {
      // Close all the open elements, up the stack
      for (var i = stack.length - 1; i >= pos; i--) {
        if (process.env.NODE_ENV !== 'production' &&
            (i > pos || !tagName) &&
            options.warn) {
          options.warn(
            ("tag <" + (stack[i].tag) + "> has no matching end tag.")
          );
        }
        if (options.end) {
          options.end(stack[i].tag, start, end);
        }
      }

      // Remove the open elements from the stack
      stack.length = pos;
      lastTag = pos && stack[pos - 1].tag;
    } else if (lowerCasedTagName === 'br') {
      if (options.start) {
        options.start(tagName, [], true, start, end);
      }
    } else if (lowerCasedTagName === 'p') {
      if (options.start) {
        options.start(tagName, [], false, start, end);
      }
      if (options.end) {
        options.end(tagName, start, end);
      }
    }
  }
}

/*  */

var splitRE = /\r?\n/g;
var replaceRE = /./g;
var isSpecialTag = makeMap('script,style,template', true);



/**
 * Parse a single-file component (*.vue) file into an SFC Descriptor Object.
 */
function parseComponent (
  content,
  options
 ) {
  if ( options === void 0 ) options = {};

  var sfc = {
    template: null,
    script: null,
    styles: [],
    customBlocks: []
  };
  var depth = 0;
  var currentBlock = null;

  function start (
    tag,
    attrs,
    unary,
    start,
    end
  ) {
    if (depth === 0) {
      currentBlock = {
        type: tag,
        content: '',
        start: end,
        attrs: attrs.reduce(function (cumulated, ref) {
          var name = ref.name;
          var value = ref.value;

          cumulated[name] = value || true;
          return cumulated
        }, Object.create(null))
      };
      if (isSpecialTag(tag)) {
        checkAttrs(currentBlock, attrs);
        if (tag === 'style') {
          sfc.styles.push(currentBlock);
        } else {
          sfc[tag] = currentBlock;
        }
      } else { // custom blocks
        sfc.customBlocks.push(currentBlock);
      }
    }
    if (!unary) {
      depth++;
    }
  }

  function checkAttrs (block, attrs) {
    for (var i = 0; i < attrs.length; i++) {
      var attr = attrs[i];
      if (attr.name === 'lang') {
        block.lang = attr.value;
      }
      if (attr.name === 'scoped') {
        block.scoped = true;
      }
      if (attr.name === 'module') {
        block.module = attr.value || true;
      }
      if (attr.name === 'src') {
        block.src = attr.value;
      }
    }
  }

  function end (tag, start, end) {
    if (depth === 1 && currentBlock) {
      currentBlock.end = start;
      var text = deindent(content.slice(currentBlock.start, currentBlock.end));
      // pad content so that linters and pre-processors can output correct
      // line numbers in errors and warnings
      if (currentBlock.type !== 'template' && options.pad) {
        text = padContent(currentBlock, options.pad) + text;
      }
      currentBlock.content = text;
      currentBlock = null;
    }
    depth--;
  }

  function padContent (block, pad) {
    if (pad === 'space') {
      return content.slice(0, block.start).replace(replaceRE, ' ')
    } else {
      var offset = content.slice(0, block.start).split(splitRE).length;
      var padChar = block.type === 'script' && !block.lang
        ? '//\n'
        : '\n';
      return Array(offset).join(padChar)
    }
  }

  parseHTML(content, {
    start: start,
    end: end
  });

  return sfc
}

/*  */

var validDivisionCharRE = /[\w).+\-_$\]]/;

function parseFilters (exp) {
  var inSingle = false;
  var inDouble = false;
  var inTemplateString = false;
  var inRegex = false;
  var curly = 0;
  var square = 0;
  var paren = 0;
  var lastFilterIndex = 0;
  var c, prev, i, expression, filters;

  for (i = 0; i < exp.length; i++) {
    prev = c;
    c = exp.charCodeAt(i);
    if (inSingle) {
      if (c === 0x27 && prev !== 0x5C) { inSingle = false; }
    } else if (inDouble) {
      if (c === 0x22 && prev !== 0x5C) { inDouble = false; }
    } else if (inTemplateString) {
      if (c === 0x60 && prev !== 0x5C) { inTemplateString = false; }
    } else if (inRegex) {
      if (c === 0x2f && prev !== 0x5C) { inRegex = false; }
    } else if (
      c === 0x7C && // pipe
      exp.charCodeAt(i + 1) !== 0x7C &&
      exp.charCodeAt(i - 1) !== 0x7C &&
      !curly && !square && !paren
    ) {
      if (expression === undefined) {
        // first filter, end of expression
        lastFilterIndex = i + 1;
        expression = exp.slice(0, i).trim();
      } else {
        pushFilter();
      }
    } else {
      switch (c) {
        case 0x22: inDouble = true; break         // "
        case 0x27: inSingle = true; break         // '
        case 0x60: inTemplateString = true; break // `
        case 0x28: paren++; break                 // (
        case 0x29: paren--; break                 // )
        case 0x5B: square++; break                // [
        case 0x5D: square--; break                // ]
        case 0x7B: curly++; break                 // {
        case 0x7D: curly--; break                 // }
      }
      if (c === 0x2f) { // /
        var j = i - 1;
        var p = (void 0);
        // find first non-whitespace prev char
        for (; j >= 0; j--) {
          p = exp.charAt(j);
          if (p !== ' ') { break }
        }
        if (!p || !validDivisionCharRE.test(p)) {
          inRegex = true;
        }
      }
    }
  }

  if (expression === undefined) {
    expression = exp.slice(0, i).trim();
  } else if (lastFilterIndex !== 0) {
    pushFilter();
  }

  function pushFilter () {
    (filters || (filters = [])).push(exp.slice(lastFilterIndex, i).trim());
    lastFilterIndex = i + 1;
  }

  if (filters) {
    for (i = 0; i < filters.length; i++) {
      expression = wrapFilter(expression, filters[i]);
    }
  }

  return expression
}

function wrapFilter (exp, filter) {
  var i = filter.indexOf('(');
  if (i < 0) {
    // _f: resolveFilter
    return ("_f(\"" + filter + "\")(" + exp + ")")
  } else {
    var name = filter.slice(0, i);
    var args = filter.slice(i + 1);
    return ("_f(\"" + name + "\")(" + exp + "," + args)
  }
}

/*  */

var defaultTagRE = /\{\{((?:.|\n)+?)\}\}/g;
var regexEscapeRE = /[-.*+?^${}()|[\]\/\\]/g;

var buildRegex = cached(function (delimiters) {
  var open = delimiters[0].replace(regexEscapeRE, '\\$&');
  var close = delimiters[1].replace(regexEscapeRE, '\\$&');
  return new RegExp(open + '((?:.|\\n)+?)' + close, 'g')
});

function parseText (
  text,
  delimiters
) {
  var tagRE = delimiters ? buildRegex(delimiters) : defaultTagRE;
  if (!tagRE.test(text)) {
    return
  }
  var tokens = [];
  var lastIndex = tagRE.lastIndex = 0;
  var match, index;
  while ((match = tagRE.exec(text))) {
    index = match.index;
    // push text token
    if (index > lastIndex) {
      tokens.push(JSON.stringify(text.slice(lastIndex, index)));
    }
    // tag token
    var exp = parseFilters(match[1].trim());
    tokens.push(("_s(" + exp + ")"));
    lastIndex = index + match[0].length;
  }
  if (lastIndex < text.length) {
    tokens.push(JSON.stringify(text.slice(lastIndex)));
  }
  return tokens.join('+')
}

/*  */
/* globals MutationObserver */

// can we use __proto__?
var hasProto = '__proto__' in {};

// Browser environment sniffing
var inBrowser = typeof window !== 'undefined';
var UA = inBrowser && window.navigator.userAgent.toLowerCase();
var isIE = UA && /msie|trident/.test(UA);
var isIE9 = UA && UA.indexOf('msie 9.0') > 0;
var isEdge = UA && UA.indexOf('edge/') > 0;
var isAndroid = UA && UA.indexOf('android') > 0;
var isIOS = UA && /iphone|ipad|ipod|ios/.test(UA);
var isChrome = UA && /chrome\/\d+/.test(UA) && !isEdge;

// this needs to be lazy-evaled because vue may be required before
// vue-server-renderer can set VUE_ENV
var _isServer;
var isServerRendering = function () {
  if (_isServer === undefined) {
    /* istanbul ignore if */
    if (!inBrowser && typeof global !== 'undefined') {
      // detect presence of vue-server-renderer and avoid
      // Webpack shimming the process
      _isServer = global['process'].env.VUE_ENV === 'server';
    } else {
      _isServer = false;
    }
  }
  return _isServer
};

// detect devtools
var devtools = inBrowser && window.__VUE_DEVTOOLS_GLOBAL_HOOK__;

/* istanbul ignore next */
function isNative (Ctor) {
  return /native code/.test(Ctor.toString())
}

var hasSymbol =
  typeof Symbol !== 'undefined' && isNative(Symbol) &&
  typeof Reflect !== 'undefined' && isNative(Reflect.ownKeys);

/**
 * Defer a task to execute it asynchronously.
 */
var nextTick = (function () {
  var callbacks = [];
  var pending = false;
  var timerFunc;

  function nextTickHandler () {
    pending = false;
    var copies = callbacks.slice(0);
    callbacks.length = 0;
    for (var i = 0; i < copies.length; i++) {
      copies[i]();
    }
  }

  // the nextTick behavior leverages the microtask queue, which can be accessed
  // via either native Promise.then or MutationObserver.
  // MutationObserver has wider support, however it is seriously bugged in
  // UIWebView in iOS >= 9.3.3 when triggered in touch event handlers. It
  // completely stops working after triggering a few times... so, if native
  // Promise is available, we will use it:
  /* istanbul ignore if */
  if (typeof Promise !== 'undefined' && isNative(Promise)) {
    var p = Promise.resolve();
    var logError = function (err) { console.error(err); };
    timerFunc = function () {
      p.then(nextTickHandler).catch(logError);
      // in problematic UIWebViews, Promise.then doesn't completely break, but
      // it can get stuck in a weird state where callbacks are pushed into the
      // microtask queue but the queue isn't being flushed, until the browser
      // needs to do some other work, e.g. handle a timer. Therefore we can
      // "force" the microtask queue to be flushed by adding an empty timer.
      if (isIOS) { setTimeout(noop); }
    };
  } else if (typeof MutationObserver !== 'undefined' && (
    isNative(MutationObserver) ||
    // PhantomJS and iOS 7.x
    MutationObserver.toString() === '[object MutationObserverConstructor]'
  )) {
    // use MutationObserver where native Promise is not available,
    // e.g. PhantomJS IE11, iOS7, Android 4.4
    var counter = 1;
    var observer = new MutationObserver(nextTickHandler);
    var textNode = document.createTextNode(String(counter));
    observer.observe(textNode, {
      characterData: true
    });
    timerFunc = function () {
      counter = (counter + 1) % 2;
      textNode.data = String(counter);
    };
  } else {
    // fallback to setTimeout
    /* istanbul ignore next */
    timerFunc = function () {
      setTimeout(nextTickHandler, 0);
    };
  }

  return function queueNextTick (cb, ctx) {
    var _resolve;
    callbacks.push(function () {
      if (cb) { cb.call(ctx); }
      if (_resolve) { _resolve(ctx); }
    });
    if (!pending) {
      pending = true;
      timerFunc();
    }
    if (!cb && typeof Promise !== 'undefined') {
      return new Promise(function (resolve) {
        _resolve = resolve;
      })
    }
  }
})();

var _Set;
/* istanbul ignore if */
if (typeof Set !== 'undefined' && isNative(Set)) {
  // use native Set when available.
  _Set = Set;
} else {
  // a non-standard Set polyfill that only works with primitive keys.
  _Set = (function () {
    function Set () {
      this.set = Object.create(null);
    }
    Set.prototype.has = function has (key) {
      return this.set[key] === true
    };
    Set.prototype.add = function add (key) {
      this.set[key] = true;
    };
    Set.prototype.clear = function clear () {
      this.set = Object.create(null);
    };

    return Set;
  }());
}

/*  */

function baseWarn (msg) {
  console.error(("[Vue compiler]: " + msg));
}

function pluckModuleFunction (
  modules,
  key
) {
  return modules
    ? modules.map(function (m) { return m[key]; }).filter(function (_) { return _; })
    : []
}

function addProp (el, name, value) {
  (el.props || (el.props = [])).push({ name: name, value: value });
}

function addAttr (el, name, value) {
  (el.attrs || (el.attrs = [])).push({ name: name, value: value });
}

function addDirective (
  el,
  name,
  rawName,
  value,
  arg,
  modifiers
) {
  (el.directives || (el.directives = [])).push({ name: name, rawName: rawName, value: value, arg: arg, modifiers: modifiers });
}

function addHandler (
  el,
  name,
  value,
  modifiers,
  important
) {
  // check capture modifier
  if (modifiers && modifiers.capture) {
    delete modifiers.capture;
    name = '!' + name; // mark the event as captured
  }
  if (modifiers && modifiers.once) {
    delete modifiers.once;
    name = '~' + name; // mark the event as once
  }
  var events;
  if (modifiers && modifiers.native) {
    delete modifiers.native;
    events = el.nativeEvents || (el.nativeEvents = {});
  } else {
    events = el.events || (el.events = {});
  }
  var newHandler = { value: value, modifiers: modifiers };
  var handlers = events[name];
  /* istanbul ignore if */
  if (Array.isArray(handlers)) {
    important ? handlers.unshift(newHandler) : handlers.push(newHandler);
  } else if (handlers) {
    events[name] = important ? [newHandler, handlers] : [handlers, newHandler];
  } else {
    events[name] = newHandler;
  }
}

function getBindingAttr (
  el,
  name,
  getStatic
) {
  var dynamicValue =
    getAndRemoveAttr(el, ':' + name) ||
    getAndRemoveAttr(el, 'v-bind:' + name);
  if (dynamicValue != null) {
    return parseFilters(dynamicValue)
  } else if (getStatic !== false) {
    var staticValue = getAndRemoveAttr(el, name);
    if (staticValue != null) {
      return JSON.stringify(staticValue)
    }
  }
}

function getAndRemoveAttr (el, name) {
  var val;
  if ((val = el.attrsMap[name]) != null) {
    var list = el.attrsList;
    for (var i = 0, l = list.length; i < l; i++) {
      if (list[i].name === name) {
        list.splice(i, 1);
        break
      }
    }
  }
  return val
}

/*  */

var onRE = /^@|^v-on:/;
var dirRE = /^v-|^@|^:/;
var forAliasRE = /(.*?)\s+(?:in|of)\s+(.*)/;
var forIteratorRE = /\((\{[^}]*\}|[^,]*),([^,]*)(?:,([^,]*))?\)/;

var argRE = /:(.*)$/;
var bindRE = /^:|^v-bind:/;
var modifierRE = /\.[^.]+/g;

var decodeHTMLCached = cached(he.decode);

// configurable state
var warn;
var delimiters;
var transforms;
var preTransforms;
var postTransforms;
var platformIsPreTag;
var platformMustUseProp;
var platformGetTagNamespace;

/**
 * Convert HTML string to AST.
 */
function parse (
  template,
  options
) {
  warn = options.warn || baseWarn;
  platformGetTagNamespace = options.getTagNamespace || no;
  platformMustUseProp = options.mustUseProp || no;
  platformIsPreTag = options.isPreTag || no;
  preTransforms = pluckModuleFunction(options.modules, 'preTransformNode');
  transforms = pluckModuleFunction(options.modules, 'transformNode');
  postTransforms = pluckModuleFunction(options.modules, 'postTransformNode');
  delimiters = options.delimiters;

  var stack = [];
  var preserveWhitespace = options.preserveWhitespace !== false;
  var root;
  var currentParent;
  var inVPre = false;
  var inPre = false;
  var warned = false;

  function warnOnce (msg) {
    if (!warned) {
      warned = true;
      warn(msg);
    }
  }

  function endPre (element) {
    // check pre state
    if (element.pre) {
      inVPre = false;
    }
    if (platformIsPreTag(element.tag)) {
      inPre = false;
    }
  }

  parseHTML(template, {
    warn: warn,
    expectHTML: options.expectHTML,
    isUnaryTag: options.isUnaryTag,
    canBeLeftOpenTag: options.canBeLeftOpenTag,
    shouldDecodeNewlines: options.shouldDecodeNewlines,
    start: function start (tag, attrs, unary) {
      // check namespace.
      // inherit parent ns if there is one
      var ns = (currentParent && currentParent.ns) || platformGetTagNamespace(tag);

      // handle IE svg bug
      /* istanbul ignore if */
      if (isIE && ns === 'svg') {
        attrs = guardIESVGBug(attrs);
      }

      var element = {
        type: 1,
        tag: tag,
        attrsList: attrs,
        attrsMap: makeAttrsMap(attrs),
        parent: currentParent,
        children: []
      };
      if (ns) {
        element.ns = ns;
      }

      if (isForbiddenTag(element) && !isServerRendering()) {
        element.forbidden = true;
        process.env.NODE_ENV !== 'production' && warn(
          'Templates should only be responsible for mapping the state to the ' +
          'UI. Avoid placing tags with side-effects in your templates, such as ' +
          "<" + tag + ">" + ', as they will not be parsed.'
        );
      }

      // apply pre-transforms
      for (var i = 0; i < preTransforms.length; i++) {
        preTransforms[i](element, options);
      }

      if (!inVPre) {
        processPre(element);
        if (element.pre) {
          inVPre = true;
        }
      }
      if (platformIsPreTag(element.tag)) {
        inPre = true;
      }
      if (inVPre) {
        processRawAttrs(element);
      } else {
        processFor(element);
        processIf(element);
        processOnce(element);
        processKey(element);

        // determine whether this is a plain element after
        // removing structural attributes
        element.plain = !element.key && !attrs.length;

        processRef(element);
        processSlot(element);
        processComponent(element);
        for (var i$1 = 0; i$1 < transforms.length; i$1++) {
          transforms[i$1](element, options);
        }
        processAttrs(element);
      }

      function checkRootConstraints (el) {
        if (process.env.NODE_ENV !== 'production') {
          if (el.tag === 'slot' || el.tag === 'template') {
            warnOnce(
              "Cannot use <" + (el.tag) + "> as component root element because it may " +
              'contain multiple nodes.'
            );
          }
          if (el.attrsMap.hasOwnProperty('v-for')) {
            warnOnce(
              'Cannot use v-for on stateful component root element because ' +
              'it renders multiple elements.'
            );
          }
        }
      }

      // tree management
      if (!root) {
        root = element;
        checkRootConstraints(root);
      } else if (!stack.length) {
        // allow root elements with v-if, v-else-if and v-else
        if (root.if && (element.elseif || element.else)) {
          checkRootConstraints(element);
          addIfCondition(root, {
            exp: element.elseif,
            block: element
          });
        } else if (process.env.NODE_ENV !== 'production') {
          warnOnce(
            "Component template should contain exactly one root element. " +
            "If you are using v-if on multiple elements, " +
            "use v-else-if to chain them instead."
          );
        }
      }
      if (currentParent && !element.forbidden) {
        if (element.elseif || element.else) {
          processIfConditions(element, currentParent);
        } else if (element.slotScope) { // scoped slot
          currentParent.plain = false;
          var name = element.slotTarget || '"default"';(currentParent.scopedSlots || (currentParent.scopedSlots = {}))[name] = element;
        } else {
          currentParent.children.push(element);
          element.parent = currentParent;
        }
      }
      if (!unary) {
        currentParent = element;
        stack.push(element);
      } else {
        endPre(element);
      }
      // apply post-transforms
      for (var i$2 = 0; i$2 < postTransforms.length; i$2++) {
        postTransforms[i$2](element, options);
      }
    },

    end: function end () {
      // remove trailing whitespace
      var element = stack[stack.length - 1];
      var lastNode = element.children[element.children.length - 1];
      if (lastNode && lastNode.type === 3 && lastNode.text === ' ' && !inPre) {
        element.children.pop();
      }
      // pop stack
      stack.length -= 1;
      currentParent = stack[stack.length - 1];
      endPre(element);
    },

    chars: function chars (text) {
      if (!currentParent) {
        if (process.env.NODE_ENV !== 'production') {
          if (text === template) {
            warnOnce(
              'Component template requires a root element, rather than just text.'
            );
          } else if ((text = text.trim())) {
            warnOnce(
              ("text \"" + text + "\" outside root element will be ignored.")
            );
          }
        }
        return
      }
      // IE textarea placeholder bug
      /* istanbul ignore if */
      if (isIE &&
          currentParent.tag === 'textarea' &&
          currentParent.attrsMap.placeholder === text) {
        return
      }
      var children = currentParent.children;
      text = inPre || text.trim()
        ? decodeHTMLCached(text)
        // only preserve whitespace if its not right after a starting tag
        : preserveWhitespace && children.length ? ' ' : '';
      if (text) {
        var expression;
        if (!inVPre && text !== ' ' && (expression = parseText(text, delimiters))) {
          children.push({
            type: 2,
            expression: expression,
            text: text
          });
        } else if (text !== ' ' || !children.length || children[children.length - 1].text !== ' ') {
          children.push({
            type: 3,
            text: text
          });
        }
      }
    }
  });
  return root
}

function processPre (el) {
  if (getAndRemoveAttr(el, 'v-pre') != null) {
    el.pre = true;
  }
}

function processRawAttrs (el) {
  var l = el.attrsList.length;
  if (l) {
    var attrs = el.attrs = new Array(l);
    for (var i = 0; i < l; i++) {
      attrs[i] = {
        name: el.attrsList[i].name,
        value: JSON.stringify(el.attrsList[i].value)
      };
    }
  } else if (!el.pre) {
    // non root node in pre blocks with no attributes
    el.plain = true;
  }
}

function processKey (el) {
  var exp = getBindingAttr(el, 'key');
  if (exp) {
    if (process.env.NODE_ENV !== 'production' && el.tag === 'template') {
      warn("<template> cannot be keyed. Place the key on real elements instead.");
    }
    el.key = exp;
  }
}

function processRef (el) {
  var ref = getBindingAttr(el, 'ref');
  if (ref) {
    el.ref = ref;
    el.refInFor = checkInFor(el);
  }
}

function processFor (el) {
  var exp;
  if ((exp = getAndRemoveAttr(el, 'v-for'))) {
    var inMatch = exp.match(forAliasRE);
    if (!inMatch) {
      process.env.NODE_ENV !== 'production' && warn(
        ("Invalid v-for expression: " + exp)
      );
      return
    }
    el.for = inMatch[2].trim();
    var alias = inMatch[1].trim();
    var iteratorMatch = alias.match(forIteratorRE);
    if (iteratorMatch) {
      el.alias = iteratorMatch[1].trim();
      el.iterator1 = iteratorMatch[2].trim();
      if (iteratorMatch[3]) {
        el.iterator2 = iteratorMatch[3].trim();
      }
    } else {
      el.alias = alias;
    }
  }
}

function processIf (el) {
  var exp = getAndRemoveAttr(el, 'v-if');
  if (exp) {
    el.if = exp;
    addIfCondition(el, {
      exp: exp,
      block: el
    });
  } else {
    if (getAndRemoveAttr(el, 'v-else') != null) {
      el.else = true;
    }
    var elseif = getAndRemoveAttr(el, 'v-else-if');
    if (elseif) {
      el.elseif = elseif;
    }
  }
}

function processIfConditions (el, parent) {
  var prev = findPrevElement(parent.children);
  if (prev && prev.if) {
    addIfCondition(prev, {
      exp: el.elseif,
      block: el
    });
  } else if (process.env.NODE_ENV !== 'production') {
    warn(
      "v-" + (el.elseif ? ('else-if="' + el.elseif + '"') : 'else') + " " +
      "used on element <" + (el.tag) + "> without corresponding v-if."
    );
  }
}

function findPrevElement (children) {
  var i = children.length;
  while (i--) {
    if (children[i].type === 1) {
      return children[i]
    } else {
      if (process.env.NODE_ENV !== 'production' && children[i].text !== ' ') {
        warn(
          "text \"" + (children[i].text.trim()) + "\" between v-if and v-else(-if) " +
          "will be ignored."
        );
      }
      children.pop();
    }
  }
}

function addIfCondition (el, condition) {
  if (!el.ifConditions) {
    el.ifConditions = [];
  }
  el.ifConditions.push(condition);
}

function processOnce (el) {
  var once$$1 = getAndRemoveAttr(el, 'v-once');
  if (once$$1 != null) {
    el.once = true;
  }
}

function processSlot (el) {
  if (el.tag === 'slot') {
    el.slotName = getBindingAttr(el, 'name');
    if (process.env.NODE_ENV !== 'production' && el.key) {
      warn(
        "`key` does not work on <slot> because slots are abstract outlets " +
        "and can possibly expand into multiple elements. " +
        "Use the key on a wrapping element instead."
      );
    }
  } else {
    var slotTarget = getBindingAttr(el, 'slot');
    if (slotTarget) {
      el.slotTarget = slotTarget === '""' ? '"default"' : slotTarget;
    }
    if (el.tag === 'template') {
      el.slotScope = getAndRemoveAttr(el, 'scope');
    }
  }
}

function processComponent (el) {
  var binding;
  if ((binding = getBindingAttr(el, 'is'))) {
    el.component = binding;
  }
  if (getAndRemoveAttr(el, 'inline-template') != null) {
    el.inlineTemplate = true;
  }
}

function processAttrs (el) {
  var list = el.attrsList;
  var i, l, name, rawName, value, modifiers, isProp;
  for (i = 0, l = list.length; i < l; i++) {
    name = rawName = list[i].name;
    value = list[i].value;
    if (dirRE.test(name)) {
      // mark element as dynamic
      el.hasBindings = true;
      // modifiers
      modifiers = parseModifiers(name);
      if (modifiers) {
        name = name.replace(modifierRE, '');
      }
      if (bindRE.test(name)) { // v-bind
        name = name.replace(bindRE, '');
        value = parseFilters(value);
        isProp = false;
        if (modifiers) {
          if (modifiers.prop) {
            isProp = true;
            name = camelize(name);
            if (name === 'innerHtml') { name = 'innerHTML'; }
          }
          if (modifiers.camel) {
            name = camelize(name);
          }
        }
        if (isProp || platformMustUseProp(el.tag, el.attrsMap.type, name)) {
          addProp(el, name, value);
        } else {
          addAttr(el, name, value);
        }
      } else if (onRE.test(name)) { // v-on
        name = name.replace(onRE, '');
        addHandler(el, name, value, modifiers);
      } else { // normal directives
        name = name.replace(dirRE, '');
        // parse arg
        var argMatch = name.match(argRE);
        var arg = argMatch && argMatch[1];
        if (arg) {
          name = name.slice(0, -(arg.length + 1));
        }
        addDirective(el, name, rawName, value, arg, modifiers);
        if (process.env.NODE_ENV !== 'production' && name === 'model') {
          checkForAliasModel(el, value);
        }
      }
    } else {
      // literal attribute
      if (process.env.NODE_ENV !== 'production') {
        var expression = parseText(value, delimiters);
        if (expression) {
          warn(
            name + "=\"" + value + "\": " +
            'Interpolation inside attributes has been removed. ' +
            'Use v-bind or the colon shorthand instead. For example, ' +
            'instead of <div id="{{ val }}">, use <div :id="val">.'
          );
        }
      }
      addAttr(el, name, JSON.stringify(value));
    }
  }
}

function checkInFor (el) {
  var parent = el;
  while (parent) {
    if (parent.for !== undefined) {
      return true
    }
    parent = parent.parent;
  }
  return false
}

function parseModifiers (name) {
  var match = name.match(modifierRE);
  if (match) {
    var ret = {};
    match.forEach(function (m) { ret[m.slice(1)] = true; });
    return ret
  }
}

function makeAttrsMap (attrs) {
  var map = {};
  for (var i = 0, l = attrs.length; i < l; i++) {
    if (process.env.NODE_ENV !== 'production' && map[attrs[i].name] && !isIE) {
      warn('duplicate attribute: ' + attrs[i].name);
    }
    map[attrs[i].name] = attrs[i].value;
  }
  return map
}

function isForbiddenTag (el) {
  return (
    el.tag === 'style' ||
    (el.tag === 'script' && (
      !el.attrsMap.type ||
      el.attrsMap.type === 'text/javascript'
    ))
  )
}

var ieNSBug = /^xmlns:NS\d+/;
var ieNSPrefix = /^NS\d+:/;

/* istanbul ignore next */
function guardIESVGBug (attrs) {
  var res = [];
  for (var i = 0; i < attrs.length; i++) {
    var attr = attrs[i];
    if (!ieNSBug.test(attr.name)) {
      attr.name = attr.name.replace(ieNSPrefix, '');
      res.push(attr);
    }
  }
  return res
}

function checkForAliasModel (el, value) {
  var _el = el;
  while (_el) {
    if (_el.for && _el.alias === value) {
      warn(
        "<" + (el.tag) + " v-model=\"" + value + "\">: " +
        "You are binding v-model directly to a v-for iteration alias. " +
        "This will not be able to modify the v-for source array because " +
        "writing to the alias is like modifying a function local variable. " +
        "Consider using an array of objects and use v-model on an object property instead."
      );
    }
    _el = _el.parent;
  }
}

/*  */

var isStaticKey;
var isPlatformReservedTag;

var genStaticKeysCached = cached(genStaticKeys$1);

/**
 * Goal of the optimizer: walk the generated template AST tree
 * and detect sub-trees that are purely static, i.e. parts of
 * the DOM that never needs to change.
 *
 * Once we detect these sub-trees, we can:
 *
 * 1. Hoist them into constants, so that we no longer need to
 *    create fresh nodes for them on each re-render;
 * 2. Completely skip them in the patching process.
 */
function optimize (root, options) {
  if (!root) { return }
  isStaticKey = genStaticKeysCached(options.staticKeys || '');
  isPlatformReservedTag = options.isReservedTag || no;
  // first pass: mark all non-static nodes.
  markStatic(root);
  // second pass: mark static roots.
  markStaticRoots(root, false);
}

function genStaticKeys$1 (keys) {
  return makeMap(
    'type,tag,attrsList,attrsMap,plain,parent,children,attrs' +
    (keys ? ',' + keys : '')
  )
}

function markStatic (node) {
  node.static = isStatic(node);
  if (node.type === 1) {
    // do not make component slot content static. this avoids
    // 1. components not able to mutate slot nodes
    // 2. static slot content fails for hot-reloading
    if (
      !isPlatformReservedTag(node.tag) &&
      node.tag !== 'slot' &&
      node.attrsMap['inline-template'] == null
    ) {
      return
    }
    for (var i = 0, l = node.children.length; i < l; i++) {
      var child = node.children[i];
      markStatic(child);
      if (!child.static) {
        node.static = false;
      }
    }
  }
}

function markStaticRoots (node, isInFor) {
  if (node.type === 1) {
    if (node.static || node.once) {
      node.staticInFor = isInFor;
    }
    // For a node to qualify as a static root, it should have children that
    // are not just static text. Otherwise the cost of hoisting out will
    // outweigh the benefits and it's better off to just always render it fresh.
    if (node.static && node.children.length && !(
      node.children.length === 1 &&
      node.children[0].type === 3
    )) {
      node.staticRoot = true;
      return
    } else {
      node.staticRoot = false;
    }
    if (node.children) {
      for (var i = 0, l = node.children.length; i < l; i++) {
        markStaticRoots(node.children[i], isInFor || !!node.for);
      }
    }
    if (node.ifConditions) {
      walkThroughConditionsBlocks(node.ifConditions, isInFor);
    }
  }
}

function walkThroughConditionsBlocks (conditionBlocks, isInFor) {
  for (var i = 1, len = conditionBlocks.length; i < len; i++) {
    markStaticRoots(conditionBlocks[i].block, isInFor);
  }
}

function isStatic (node) {
  if (node.type === 2) { // expression
    return false
  }
  if (node.type === 3) { // text
    return true
  }
  return !!(node.pre || (
    !node.hasBindings && // no dynamic bindings
    !node.if && !node.for && // not v-if or v-for or v-else
    !isBuiltInTag(node.tag) && // not a built-in
    isPlatformReservedTag(node.tag) && // not a component
    !isDirectChildOfTemplateFor(node) &&
    Object.keys(node).every(isStaticKey)
  ))
}

function isDirectChildOfTemplateFor (node) {
  while (node.parent) {
    node = node.parent;
    if (node.tag !== 'template') {
      return false
    }
    if (node.for) {
      return true
    }
  }
  return false
}

/*  */

var fnExpRE = /^\s*([\w$_]+|\([^)]*?\))\s*=>|^function\s*\(/;
var simplePathRE = /^\s*[A-Za-z_$][\w$]*(?:\.[A-Za-z_$][\w$]*|\['.*?']|\[".*?"]|\[\d+]|\[[A-Za-z_$][\w$]*])*\s*$/;

// keyCode aliases
var keyCodes = {
  esc: 27,
  tab: 9,
  enter: 13,
  space: 32,
  up: 38,
  left: 37,
  right: 39,
  down: 40,
  'delete': [8, 46]
};

// #4868: modifiers that prevent the execution of the listener
// need to explicitly return null so that we can determine whether to remove
// the listener for .once
var genGuard = function (condition) { return ("if(" + condition + ")return null;"); };

var modifierCode = {
  stop: '$event.stopPropagation();',
  prevent: '$event.preventDefault();',
  self: genGuard("$event.target !== $event.currentTarget"),
  ctrl: genGuard("!$event.ctrlKey"),
  shift: genGuard("!$event.shiftKey"),
  alt: genGuard("!$event.altKey"),
  meta: genGuard("!$event.metaKey"),
  left: genGuard("'button' in $event && $event.button !== 0"),
  middle: genGuard("'button' in $event && $event.button !== 1"),
  right: genGuard("'button' in $event && $event.button !== 2")
};

function genHandlers (events, native) {
  var res = native ? 'nativeOn:{' : 'on:{';
  for (var name in events) {
    res += "\"" + name + "\":" + (genHandler(name, events[name])) + ",";
  }
  return res.slice(0, -1) + '}'
}

function genHandler (
  name,
  handler
) {
  if (!handler) {
    return 'function(){}'
  }

  if (Array.isArray(handler)) {
    return ("[" + (handler.map(function (handler) { return genHandler(name, handler); }).join(',')) + "]")
  }

  var isMethodPath = simplePathRE.test(handler.value);
  var isFunctionExpression = fnExpRE.test(handler.value);

  if (!handler.modifiers) {
    return isMethodPath || isFunctionExpression
      ? handler.value
      : ("function($event){" + (handler.value) + "}") // inline statement
  } else {
    var code = '';
    var genModifierCode = '';
    var keys = [];
    for (var key in handler.modifiers) {
      if (modifierCode[key]) {
        genModifierCode += modifierCode[key];
        // left/right
        if (keyCodes[key]) {
          keys.push(key);
        }
      } else {
        keys.push(key);
      }
    }
    if (keys.length) {
      code += genKeyFilter(keys);
    }
    // Make sure modifiers like prevent and stop get executed after key filtering
    if (genModifierCode) {
      code += genModifierCode;
    }
    var handlerCode = isMethodPath
      ? handler.value + '($event)'
      : isFunctionExpression
        ? ("(" + (handler.value) + ")($event)")
        : handler.value;
    return ("function($event){" + code + handlerCode + "}")
  }
}

function genKeyFilter (keys) {
  return ("if(!('button' in $event)&&" + (keys.map(genFilterCode).join('&&')) + ")return null;")
}

function genFilterCode (key) {
  var keyVal = parseInt(key, 10);
  if (keyVal) {
    return ("$event.keyCode!==" + keyVal)
  }
  var alias = keyCodes[key];
  return ("_k($event.keyCode," + (JSON.stringify(key)) + (alias ? ',' + JSON.stringify(alias) : '') + ")")
}

/*  */

function bind$1 (el, dir) {
  el.wrapData = function (code) {
    return ("_b(" + code + ",'" + (el.tag) + "'," + (dir.value) + (dir.modifiers && dir.modifiers.prop ? ',true' : '') + ")")
  };
}

/*  */

var baseDirectives = {
  bind: bind$1,
  cloak: noop
};

/*  */

// configurable state
var warn$1;
var transforms$1;
var dataGenFns;
var platformDirectives;
var isPlatformReservedTag$1;
var staticRenderFns;
var onceCount;
var currentOptions;

function generate (
  ast,
  options
) {
  // save previous staticRenderFns so generate calls can be nested
  var prevStaticRenderFns = staticRenderFns;
  var currentStaticRenderFns = staticRenderFns = [];
  var prevOnceCount = onceCount;
  onceCount = 0;
  currentOptions = options;
  warn$1 = options.warn || baseWarn;
  transforms$1 = pluckModuleFunction(options.modules, 'transformCode');
  dataGenFns = pluckModuleFunction(options.modules, 'genData');
  platformDirectives = options.directives || {};
  isPlatformReservedTag$1 = options.isReservedTag || no;
  var code = ast ? genElement(ast) : '_c("div")';
  staticRenderFns = prevStaticRenderFns;
  onceCount = prevOnceCount;
  return {
    render: ("with(this){return " + code + "}"),
    staticRenderFns: currentStaticRenderFns
  }
}

function genElement (el) {
  if (el.staticRoot && !el.staticProcessed) {
    return genStatic(el)
  } else if (el.once && !el.onceProcessed) {
    return genOnce(el)
  } else if (el.for && !el.forProcessed) {
    return genFor(el)
  } else if (el.if && !el.ifProcessed) {
    return genIf(el)
  } else if (el.tag === 'template' && !el.slotTarget) {
    return genChildren(el) || 'void 0'
  } else if (el.tag === 'slot') {
    return genSlot(el)
  } else {
    // component or element
    var code;
    if (el.component) {
      code = genComponent(el.component, el);
    } else {
      var data = el.plain ? undefined : genData(el);

      var children = el.inlineTemplate ? null : genChildren(el, true);
      code = "_c('" + (el.tag) + "'" + (data ? ("," + data) : '') + (children ? ("," + children) : '') + ")";
    }
    // module transforms
    for (var i = 0; i < transforms$1.length; i++) {
      code = transforms$1[i](el, code);
    }
    return code
  }
}

// hoist static sub-trees out
function genStatic (el) {
  el.staticProcessed = true;
  staticRenderFns.push(("with(this){return " + (genElement(el)) + "}"));
  return ("_m(" + (staticRenderFns.length - 1) + (el.staticInFor ? ',true' : '') + ")")
}

// v-once
function genOnce (el) {
  el.onceProcessed = true;
  if (el.if && !el.ifProcessed) {
    return genIf(el)
  } else if (el.staticInFor) {
    var key = '';
    var parent = el.parent;
    while (parent) {
      if (parent.for) {
        key = parent.key;
        break
      }
      parent = parent.parent;
    }
    if (!key) {
      process.env.NODE_ENV !== 'production' && warn$1(
        "v-once can only be used inside v-for that is keyed. "
      );
      return genElement(el)
    }
    return ("_o(" + (genElement(el)) + "," + (onceCount++) + (key ? ("," + key) : "") + ")")
  } else {
    return genStatic(el)
  }
}

function genIf (el) {
  el.ifProcessed = true; // avoid recursion
  return genIfConditions(el.ifConditions.slice())
}

function genIfConditions (conditions) {
  if (!conditions.length) {
    return '_e()'
  }

  var condition = conditions.shift();
  if (condition.exp) {
    return ("(" + (condition.exp) + ")?" + (genTernaryExp(condition.block)) + ":" + (genIfConditions(conditions)))
  } else {
    return ("" + (genTernaryExp(condition.block)))
  }

  // v-if with v-once should generate code like (a)?_m(0):_m(1)
  function genTernaryExp (el) {
    return el.once ? genOnce(el) : genElement(el)
  }
}

function genFor (el) {
  var exp = el.for;
  var alias = el.alias;
  var iterator1 = el.iterator1 ? ("," + (el.iterator1)) : '';
  var iterator2 = el.iterator2 ? ("," + (el.iterator2)) : '';

  if (
    process.env.NODE_ENV !== 'production' &&
    maybeComponent(el) && el.tag !== 'slot' && el.tag !== 'template' && !el.key
  ) {
    warn$1(
      "<" + (el.tag) + " v-for=\"" + alias + " in " + exp + "\">: component lists rendered with " +
      "v-for should have explicit keys. " +
      "See https://vuejs.org/guide/list.html#key for more info.",
      true /* tip */
    );
  }

  el.forProcessed = true; // avoid recursion
  return "_l((" + exp + ")," +
    "function(" + alias + iterator1 + iterator2 + "){" +
      "return " + (genElement(el)) +
    '})'
}

function genData (el) {
  var data = '{';

  // directives first.
  // directives may mutate the el's other properties before they are generated.
  var dirs = genDirectives(el);
  if (dirs) { data += dirs + ','; }

  // key
  if (el.key) {
    data += "key:" + (el.key) + ",";
  }
  // ref
  if (el.ref) {
    data += "ref:" + (el.ref) + ",";
  }
  if (el.refInFor) {
    data += "refInFor:true,";
  }
  // pre
  if (el.pre) {
    data += "pre:true,";
  }
  // record original tag name for components using "is" attribute
  if (el.component) {
    data += "tag:\"" + (el.tag) + "\",";
  }
  // module data generation functions
  for (var i = 0; i < dataGenFns.length; i++) {
    data += dataGenFns[i](el);
  }
  // attributes
  if (el.attrs) {
    data += "attrs:{" + (genProps(el.attrs)) + "},";
  }
  // DOM props
  if (el.props) {
    data += "domProps:{" + (genProps(el.props)) + "},";
  }
  // event handlers
  if (el.events) {
    data += (genHandlers(el.events)) + ",";
  }
  if (el.nativeEvents) {
    data += (genHandlers(el.nativeEvents, true)) + ",";
  }
  // slot target
  if (el.slotTarget) {
    data += "slot:" + (el.slotTarget) + ",";
  }
  // scoped slots
  if (el.scopedSlots) {
    data += (genScopedSlots(el.scopedSlots)) + ",";
  }
  // component v-model
  if (el.model) {
    data += "model:{value:" + (el.model.value) + ",callback:" + (el.model.callback) + ",expression:" + (el.model.expression) + "},";
  }
  // inline-template
  if (el.inlineTemplate) {
    var inlineTemplate = genInlineTemplate(el);
    if (inlineTemplate) {
      data += inlineTemplate + ",";
    }
  }
  data = data.replace(/,$/, '') + '}';
  // v-bind data wrap
  if (el.wrapData) {
    data = el.wrapData(data);
  }
  return data
}

function genDirectives (el) {
  var dirs = el.directives;
  if (!dirs) { return }
  var res = 'directives:[';
  var hasRuntime = false;
  var i, l, dir, needRuntime;
  for (i = 0, l = dirs.length; i < l; i++) {
    dir = dirs[i];
    needRuntime = true;
    var gen = platformDirectives[dir.name] || baseDirectives[dir.name];
    if (gen) {
      // compile-time directive that manipulates AST.
      // returns true if it also needs a runtime counterpart.
      needRuntime = !!gen(el, dir, warn$1);
    }
    if (needRuntime) {
      hasRuntime = true;
      res += "{name:\"" + (dir.name) + "\",rawName:\"" + (dir.rawName) + "\"" + (dir.value ? (",value:(" + (dir.value) + "),expression:" + (JSON.stringify(dir.value))) : '') + (dir.arg ? (",arg:\"" + (dir.arg) + "\"") : '') + (dir.modifiers ? (",modifiers:" + (JSON.stringify(dir.modifiers))) : '') + "},";
    }
  }
  if (hasRuntime) {
    return res.slice(0, -1) + ']'
  }
}

function genInlineTemplate (el) {
  var ast = el.children[0];
  if (process.env.NODE_ENV !== 'production' && (
    el.children.length > 1 || ast.type !== 1
  )) {
    warn$1('Inline-template components must have exactly one child element.');
  }
  if (ast.type === 1) {
    var inlineRenderFns = generate(ast, currentOptions);
    return ("inlineTemplate:{render:function(){" + (inlineRenderFns.render) + "},staticRenderFns:[" + (inlineRenderFns.staticRenderFns.map(function (code) { return ("function(){" + code + "}"); }).join(',')) + "]}")
  }
}

function genScopedSlots (slots) {
  return ("scopedSlots:_u([" + (Object.keys(slots).map(function (key) { return genScopedSlot(key, slots[key]); }).join(',')) + "])")
}

function genScopedSlot (key, el) {
  return "[" + key + ",function(" + (String(el.attrsMap.scope)) + "){" +
    "return " + (el.tag === 'template'
      ? genChildren(el) || 'void 0'
      : genElement(el)) + "}]"
}

function genChildren (el, checkSkip) {
  var children = el.children;
  if (children.length) {
    var el$1 = children[0];
    // optimize single v-for
    if (children.length === 1 &&
        el$1.for &&
        el$1.tag !== 'template' &&
        el$1.tag !== 'slot') {
      return genElement(el$1)
    }
    var normalizationType = checkSkip ? getNormalizationType(children) : 0;
    return ("[" + (children.map(genNode).join(',')) + "]" + (normalizationType ? ("," + normalizationType) : ''))
  }
}

// determine the normalization needed for the children array.
// 0: no normalization needed
// 1: simple normalization needed (possible 1-level deep nested array)
// 2: full normalization needed
function getNormalizationType (children) {
  var res = 0;
  for (var i = 0; i < children.length; i++) {
    var el = children[i];
    if (el.type !== 1) {
      continue
    }
    if (needsNormalization(el) ||
        (el.ifConditions && el.ifConditions.some(function (c) { return needsNormalization(c.block); }))) {
      res = 2;
      break
    }
    if (maybeComponent(el) ||
        (el.ifConditions && el.ifConditions.some(function (c) { return maybeComponent(c.block); }))) {
      res = 1;
    }
  }
  return res
}

function needsNormalization (el) {
  return el.for !== undefined || el.tag === 'template' || el.tag === 'slot'
}

function maybeComponent (el) {
  return !isPlatformReservedTag$1(el.tag)
}

function genNode (node) {
  if (node.type === 1) {
    return genElement(node)
  } else {
    return genText(node)
  }
}

function genText (text) {
  return ("_v(" + (text.type === 2
    ? text.expression // no need for () because already wrapped in _s()
    : transformSpecialNewlines(JSON.stringify(text.text))) + ")")
}

function genSlot (el) {
  var slotName = el.slotName || '"default"';
  var children = genChildren(el);
  var res = "_t(" + slotName + (children ? ("," + children) : '');
  var attrs = el.attrs && ("{" + (el.attrs.map(function (a) { return ((camelize(a.name)) + ":" + (a.value)); }).join(',')) + "}");
  var bind$$1 = el.attrsMap['v-bind'];
  if ((attrs || bind$$1) && !children) {
    res += ",null";
  }
  if (attrs) {
    res += "," + attrs;
  }
  if (bind$$1) {
    res += (attrs ? '' : ',null') + "," + bind$$1;
  }
  return res + ')'
}

// componentName is el.component, take it as argument to shun flow's pessimistic refinement
function genComponent (componentName, el) {
  var children = el.inlineTemplate ? null : genChildren(el, true);
  return ("_c(" + componentName + "," + (genData(el)) + (children ? ("," + children) : '') + ")")
}

function genProps (props) {
  var res = '';
  for (var i = 0; i < props.length; i++) {
    var prop = props[i];
    res += "\"" + (prop.name) + "\":" + (transformSpecialNewlines(prop.value)) + ",";
  }
  return res.slice(0, -1)
}

// #3895, #4268
function transformSpecialNewlines (text) {
  return text
    .replace(/\u2028/g, '\\u2028')
    .replace(/\u2029/g, '\\u2029')
}

/*  */

// these keywords should not appear inside expressions, but operators like
// typeof, instanceof and in are allowed
var prohibitedKeywordRE = new RegExp('\\b' + (
  'do,if,for,let,new,try,var,case,else,with,await,break,catch,class,const,' +
  'super,throw,while,yield,delete,export,import,return,switch,default,' +
  'extends,finally,continue,debugger,function,arguments'
).split(',').join('\\b|\\b') + '\\b');

// these unary operators should not be used as property/method names
var unaryOperatorsRE = new RegExp('\\b' + (
  'delete,typeof,void'
).split(',').join('\\s*\\([^\\)]*\\)|\\b') + '\\s*\\([^\\)]*\\)');

// check valid identifier for v-for
var identRE = /[A-Za-z_$][\w$]*/;

// strip strings in expressions
var stripStringRE = /'(?:[^'\\]|\\.)*'|"(?:[^"\\]|\\.)*"|`(?:[^`\\]|\\.)*\$\{|\}(?:[^`\\]|\\.)*`|`(?:[^`\\]|\\.)*`/g;

// detect problematic expressions in a template
function detectErrors (ast) {
  var errors = [];
  if (ast) {
    checkNode(ast, errors);
  }
  return errors
}

function checkNode (node, errors) {
  if (node.type === 1) {
    for (var name in node.attrsMap) {
      if (dirRE.test(name)) {
        var value = node.attrsMap[name];
        if (value) {
          if (name === 'v-for') {
            checkFor(node, ("v-for=\"" + value + "\""), errors);
          } else if (onRE.test(name)) {
            checkEvent(value, (name + "=\"" + value + "\""), errors);
          } else {
            checkExpression(value, (name + "=\"" + value + "\""), errors);
          }
        }
      }
    }
    if (node.children) {
      for (var i = 0; i < node.children.length; i++) {
        checkNode(node.children[i], errors);
      }
    }
  } else if (node.type === 2) {
    checkExpression(node.expression, node.text, errors);
  }
}

function checkEvent (exp, text, errors) {
  var keywordMatch = exp.replace(stripStringRE, '').match(unaryOperatorsRE);
  if (keywordMatch) {
    errors.push(
      "avoid using JavaScript unary operator as property name: " +
      "\"" + (keywordMatch[0]) + "\" in expression " + (text.trim())
    );
  }
  checkExpression(exp, text, errors);
}

function checkFor (node, text, errors) {
  checkExpression(node.for || '', text, errors);
  checkIdentifier(node.alias, 'v-for alias', text, errors);
  checkIdentifier(node.iterator1, 'v-for iterator', text, errors);
  checkIdentifier(node.iterator2, 'v-for iterator', text, errors);
}

function checkIdentifier (ident, type, text, errors) {
  if (typeof ident === 'string' && !identRE.test(ident)) {
    errors.push(("invalid " + type + " \"" + ident + "\" in expression: " + (text.trim())));
  }
}

function checkExpression (exp, text, errors) {
  try {
    new Function(("return " + exp));
  } catch (e) {
    var keywordMatch = exp.replace(stripStringRE, '').match(prohibitedKeywordRE);
    if (keywordMatch) {
      errors.push(
        "avoid using JavaScript keyword as property name: " +
        "\"" + (keywordMatch[0]) + "\" in expression " + (text.trim())
      );
    } else {
      errors.push(("invalid expression: " + (text.trim())));
    }
  }
}

/*  */

var config = {
  /**
   * Option merge strategies (used in core/util/options)
   */
  optionMergeStrategies: Object.create(null),

  /**
   * Whether to suppress warnings.
   */
  silent: false,

  /**
   * Show production mode tip message on boot?
   */
  productionTip: process.env.NODE_ENV !== 'production',

  /**
   * Whether to enable devtools
   */
  devtools: process.env.NODE_ENV !== 'production',

  /**
   * Whether to record perf
   */
  performance: false,

  /**
   * Error handler for watcher errors
   */
  errorHandler: null,

  /**
   * Ignore certain custom elements
   */
  ignoredElements: [],

  /**
   * Custom user key aliases for v-on
   */
  keyCodes: Object.create(null),

  /**
   * Check if a tag is reserved so that it cannot be registered as a
   * component. This is platform-dependent and may be overwritten.
   */
  isReservedTag: no,

  /**
   * Check if a tag is an unknown element.
   * Platform-dependent.
   */
  isUnknownElement: no,

  /**
   * Get the namespace of an element
   */
  getTagNamespace: noop,

  /**
   * Parse the real tag name for the specific platform.
   */
  parsePlatformTagName: identity,

  /**
   * Check if an attribute must be bound using property, e.g. value
   * Platform-dependent.
   */
  mustUseProp: no,

  /**
   * List of asset types that a component can own.
   */
  _assetTypes: [
    'component',
    'directive',
    'filter'
  ],

  /**
   * List of lifecycle hooks.
   */
  _lifecycleHooks: [
    'beforeCreate',
    'created',
    'beforeMount',
    'mounted',
    'beforeUpdate',
    'updated',
    'beforeDestroy',
    'destroyed',
    'activated',
    'deactivated'
  ],

  /**
   * Max circular updates allowed in a scheduler flush cycle.
   */
  _maxUpdateCount: 100
};

var warn$2 = noop;
var tip = noop;
var formatComponentName;

if (process.env.NODE_ENV !== 'production') {
  var hasConsole = typeof console !== 'undefined';
  var classifyRE = /(?:^|[-_])(\w)/g;
  var classify = function (str) { return str
    .replace(classifyRE, function (c) { return c.toUpperCase(); })
    .replace(/[-_]/g, ''); };

  warn$2 = function (msg, vm) {
    if (hasConsole && (!config.silent)) {
      console.error("[Vue warn]: " + msg + " " + (
        vm ? formatLocation(formatComponentName(vm)) : ''
      ));
    }
  };

  tip = function (msg, vm) {
    if (hasConsole && (!config.silent)) {
      console.warn("[Vue tip]: " + msg + " " + (
        vm ? formatLocation(formatComponentName(vm)) : ''
      ));
    }
  };

  formatComponentName = function (vm, includeFile) {
    if (vm.$root === vm) {
      return '<Root>'
    }
    var name = typeof vm === 'string'
      ? vm
      : typeof vm === 'function' && vm.options
        ? vm.options.name
        : vm._isVue
          ? vm.$options.name || vm.$options._componentTag
          : vm.name;

    var file = vm._isVue && vm.$options.__file;
    if (!name && file) {
      var match = file.match(/([^/\\]+)\.vue$/);
      name = match && match[1];
    }

    return (
      (name ? ("<" + (classify(name)) + ">") : "<Anonymous>") +
      (file && includeFile !== false ? (" at " + file) : '')
    )
  };

  var formatLocation = function (str) {
    if (str === "<Anonymous>") {
      str += " - use the \"name\" option for better debugging messages.";
    }
    return ("\n(found in " + str + ")")
  };
}

/*  */

function baseCompile (
  template,
  options
) {
  var ast = parse(template.trim(), options);
  optimize(ast, options);
  var code = generate(ast, options);
  return {
    ast: ast,
    render: code.render,
    staticRenderFns: code.staticRenderFns
  }
}

function makeFunction (code, errors) {
  try {
    return new Function(code)
  } catch (err) {
    errors.push({ err: err, code: code });
    return noop
  }
}

function createCompiler (baseOptions) {
  var functionCompileCache = Object.create(null);

  function compile (
    template,
    options
  ) {
    var finalOptions = Object.create(baseOptions);
    var errors = [];
    var tips = [];
    finalOptions.warn = function (msg, tip$$1) {
      (tip$$1 ? tips : errors).push(msg);
    };

    if (options) {
      // merge custom modules
      if (options.modules) {
        finalOptions.modules = (baseOptions.modules || []).concat(options.modules);
      }
      // merge custom directives
      if (options.directives) {
        finalOptions.directives = extend(
          Object.create(baseOptions.directives),
          options.directives
        );
      }
      // copy other options
      for (var key in options) {
        if (key !== 'modules' && key !== 'directives') {
          finalOptions[key] = options[key];
        }
      }
    }

    var compiled = baseCompile(template, finalOptions);
    if (process.env.NODE_ENV !== 'production') {
      errors.push.apply(errors, detectErrors(compiled.ast));
    }
    compiled.errors = errors;
    compiled.tips = tips;
    return compiled
  }

  function compileToFunctions (
    template,
    options,
    vm
  ) {
    options = options || {};

    /* istanbul ignore if */
    if (process.env.NODE_ENV !== 'production') {
      // detect possible CSP restriction
      try {
        new Function('return 1');
      } catch (e) {
        if (e.toString().match(/unsafe-eval|CSP/)) {
          warn$2(
            'It seems you are using the standalone build of Vue.js in an ' +
            'environment with Content Security Policy that prohibits unsafe-eval. ' +
            'The template compiler cannot work in this environment. Consider ' +
            'relaxing the policy to allow unsafe-eval or pre-compiling your ' +
            'templates into render functions.'
          );
        }
      }
    }

    // check cache
    var key = options.delimiters
      ? String(options.delimiters) + template
      : template;
    if (functionCompileCache[key]) {
      return functionCompileCache[key]
    }

    // compile
    var compiled = compile(template, options);

    // check compilation errors/tips
    if (process.env.NODE_ENV !== 'production') {
      if (compiled.errors && compiled.errors.length) {
        warn$2(
          "Error compiling template:\n\n" + template + "\n\n" +
          compiled.errors.map(function (e) { return ("- " + e); }).join('\n') + '\n',
          vm
        );
      }
      if (compiled.tips && compiled.tips.length) {
        compiled.tips.forEach(function (msg) { return tip(msg, vm); });
      }
    }

    // turn code into functions
    var res = {};
    var fnGenErrors = [];
    res.render = makeFunction(compiled.render, fnGenErrors);
    var l = compiled.staticRenderFns.length;
    res.staticRenderFns = new Array(l);
    for (var i = 0; i < l; i++) {
      res.staticRenderFns[i] = makeFunction(compiled.staticRenderFns[i], fnGenErrors);
    }

    // check function generation errors.
    // this should only happen if there is a bug in the compiler itself.
    // mostly for codegen development use
    /* istanbul ignore if */
    if (process.env.NODE_ENV !== 'production') {
      if ((!compiled.errors || !compiled.errors.length) && fnGenErrors.length) {
        warn$2(
          "Failed to generate render function:\n\n" +
          fnGenErrors.map(function (ref) {
            var err = ref.err;
            var code = ref.code;

            return ((err.toString()) + " in\n\n" + code + "\n");
        }).join('\n'),
          vm
        );
      }
    }

    return (functionCompileCache[key] = res)
  }

  return {
    compile: compile,
    compileToFunctions: compileToFunctions
  }
}

/*  */

function transformNode (el, options) {
  var warn = options.warn || baseWarn;
  var staticClass = getAndRemoveAttr(el, 'class');
  if (process.env.NODE_ENV !== 'production' && staticClass) {
    var expression = parseText(staticClass, options.delimiters);
    if (expression) {
      warn(
        "class=\"" + staticClass + "\": " +
        'Interpolation inside attributes has been removed. ' +
        'Use v-bind or the colon shorthand instead. For example, ' +
        'instead of <div class="{{ val }}">, use <div :class="val">.'
      );
    }
  }
  if (staticClass) {
    el.staticClass = JSON.stringify(staticClass);
  }
  var classBinding = getBindingAttr(el, 'class', false /* getStatic */);
  if (classBinding) {
    el.classBinding = classBinding;
  }
}

function genData$1 (el) {
  var data = '';
  if (el.staticClass) {
    data += "staticClass:" + (el.staticClass) + ",";
  }
  if (el.classBinding) {
    data += "class:" + (el.classBinding) + ",";
  }
  return data
}

var klass = {
  staticKeys: ['staticClass'],
  transformNode: transformNode,
  genData: genData$1
};

/*  */

var parseStyleText = cached(function (cssText) {
  var res = {};
  var listDelimiter = /;(?![^(]*\))/g;
  var propertyDelimiter = /:(.+)/;
  cssText.split(listDelimiter).forEach(function (item) {
    if (item) {
      var tmp = item.split(propertyDelimiter);
      tmp.length > 1 && (res[tmp[0].trim()] = tmp[1].trim());
    }
  });
  return res
});

// normalize possible array / string values into Object


/**
 * parent component style should be after child's
 * so that parent component's style could override it
 */

/*  */

function transformNode$1 (el, options) {
  var warn = options.warn || baseWarn;
  var staticStyle = getAndRemoveAttr(el, 'style');
  if (staticStyle) {
    /* istanbul ignore if */
    if (process.env.NODE_ENV !== 'production') {
      var expression = parseText(staticStyle, options.delimiters);
      if (expression) {
        warn(
          "style=\"" + staticStyle + "\": " +
          'Interpolation inside attributes has been removed. ' +
          'Use v-bind or the colon shorthand instead. For example, ' +
          'instead of <div style="{{ val }}">, use <div :style="val">.'
        );
      }
    }
    el.staticStyle = JSON.stringify(parseStyleText(staticStyle));
  }

  var styleBinding = getBindingAttr(el, 'style', false /* getStatic */);
  if (styleBinding) {
    el.styleBinding = styleBinding;
  }
}

function genData$2 (el) {
  var data = '';
  if (el.staticStyle) {
    data += "staticStyle:" + (el.staticStyle) + ",";
  }
  if (el.styleBinding) {
    data += "style:(" + (el.styleBinding) + "),";
  }
  return data
}

var style = {
  staticKeys: ['staticStyle'],
  transformNode: transformNode$1,
  genData: genData$2
};

var modules = [
  klass,
  style
];

/*  */

/**
 * Cross-platform code generation for component v-model
 */
function genComponentModel (
  el,
  value,
  modifiers
) {
  var ref = modifiers || {};
  var number = ref.number;
  var trim = ref.trim;

  var baseValueExpression = '$$v';
  var valueExpression = baseValueExpression;
  if (trim) {
    valueExpression =
      "(typeof " + baseValueExpression + " === 'string'" +
        "? " + baseValueExpression + ".trim()" +
        ": " + baseValueExpression + ")";
  }
  if (number) {
    valueExpression = "_n(" + valueExpression + ")";
  }
  var assignment = genAssignmentCode(value, valueExpression);

  el.model = {
    value: ("(" + value + ")"),
    expression: ("\"" + value + "\""),
    callback: ("function (" + baseValueExpression + ") {" + assignment + "}")
  };
}

/**
 * Cross-platform codegen helper for generating v-model value assignment code.
 */
function genAssignmentCode (
  value,
  assignment
) {
  var modelRs = parseModel(value);
  if (modelRs.idx === null) {
    return (value + "=" + assignment)
  } else {
    return "var $$exp = " + (modelRs.exp) + ", $$idx = " + (modelRs.idx) + ";" +
      "if (!Array.isArray($$exp)){" +
        value + "=" + assignment + "}" +
      "else{$$exp.splice($$idx, 1, " + assignment + ")}"
  }
}

/**
 * parse directive model to do the array update transform. a[idx] = val => $$a.splice($$idx, 1, val)
 *
 * for loop possible cases:
 *
 * - test
 * - test[idx]
 * - test[test1[idx]]
 * - test["a"][idx]
 * - xxx.test[a[a].test1[idx]]
 * - test.xxx.a["asa"][test1[idx]]
 *
 */

var len;
var str;
var chr;
var index;
var expressionPos;
var expressionEndPos;

function parseModel (val) {
  str = val;
  len = str.length;
  index = expressionPos = expressionEndPos = 0;

  if (val.indexOf('[') < 0 || val.lastIndexOf(']') < len - 1) {
    return {
      exp: val,
      idx: null
    }
  }

  while (!eof()) {
    chr = next();
    /* istanbul ignore if */
    if (isStringStart(chr)) {
      parseString(chr);
    } else if (chr === 0x5B) {
      parseBracket(chr);
    }
  }

  return {
    exp: val.substring(0, expressionPos),
    idx: val.substring(expressionPos + 1, expressionEndPos)
  }
}

function next () {
  return str.charCodeAt(++index)
}

function eof () {
  return index >= len
}

function isStringStart (chr) {
  return chr === 0x22 || chr === 0x27
}

function parseBracket (chr) {
  var inBracket = 1;
  expressionPos = index;
  while (!eof()) {
    chr = next();
    if (isStringStart(chr)) {
      parseString(chr);
      continue
    }
    if (chr === 0x5B) { inBracket++; }
    if (chr === 0x5D) { inBracket--; }
    if (inBracket === 0) {
      expressionEndPos = index;
      break
    }
  }
}

function parseString (chr) {
  var stringQuote = chr;
  while (!eof()) {
    chr = next();
    if (chr === stringQuote) {
      break
    }
  }
}

/*  */

var warn$3;

// in some cases, the event used has to be determined at runtime
// so we used some reserved tokens during compile.
var RANGE_TOKEN = '__r';
var CHECKBOX_RADIO_TOKEN = '__c';

function model (
  el,
  dir,
  _warn
) {
  warn$3 = _warn;
  var value = dir.value;
  var modifiers = dir.modifiers;
  var tag = el.tag;
  var type = el.attrsMap.type;

  if (process.env.NODE_ENV !== 'production') {
    var dynamicType = el.attrsMap['v-bind:type'] || el.attrsMap[':type'];
    if (tag === 'input' && dynamicType) {
      warn$3(
        "<input :type=\"" + dynamicType + "\" v-model=\"" + value + "\">:\n" +
        "v-model does not support dynamic input types. Use v-if branches instead."
      );
    }
    // inputs with type="file" are read only and setting the input's
    // value will throw an error.
    if (tag === 'input' && type === 'file') {
      warn$3(
        "<" + (el.tag) + " v-model=\"" + value + "\" type=\"file\">:\n" +
        "File inputs are read only. Use a v-on:change listener instead."
      );
    }
  }

  if (tag === 'select') {
    genSelect(el, value, modifiers);
  } else if (tag === 'input' && type === 'checkbox') {
    genCheckboxModel(el, value, modifiers);
  } else if (tag === 'input' && type === 'radio') {
    genRadioModel(el, value, modifiers);
  } else if (tag === 'input' || tag === 'textarea') {
    genDefaultModel(el, value, modifiers);
  } else if (!config.isReservedTag(tag)) {
    genComponentModel(el, value, modifiers);
    // component v-model doesn't need extra runtime
    return false
  } else if (process.env.NODE_ENV !== 'production') {
    warn$3(
      "<" + (el.tag) + " v-model=\"" + value + "\">: " +
      "v-model is not supported on this element type. " +
      'If you are working with contenteditable, it\'s recommended to ' +
      'wrap a library dedicated for that purpose inside a custom component.'
    );
  }

  // ensure runtime directive metadata
  return true
}

function genCheckboxModel (
  el,
  value,
  modifiers
) {
  var number = modifiers && modifiers.number;
  var valueBinding = getBindingAttr(el, 'value') || 'null';
  var trueValueBinding = getBindingAttr(el, 'true-value') || 'true';
  var falseValueBinding = getBindingAttr(el, 'false-value') || 'false';
  addProp(el, 'checked',
    "Array.isArray(" + value + ")" +
      "?_i(" + value + "," + valueBinding + ")>-1" + (
        trueValueBinding === 'true'
          ? (":(" + value + ")")
          : (":_q(" + value + "," + trueValueBinding + ")")
      )
  );
  addHandler(el, CHECKBOX_RADIO_TOKEN,
    "var $$a=" + value + "," +
        '$$el=$event.target,' +
        "$$c=$$el.checked?(" + trueValueBinding + "):(" + falseValueBinding + ");" +
    'if(Array.isArray($$a)){' +
      "var $$v=" + (number ? '_n(' + valueBinding + ')' : valueBinding) + "," +
          '$$i=_i($$a,$$v);' +
      "if($$c){$$i<0&&(" + value + "=$$a.concat($$v))}" +
      "else{$$i>-1&&(" + value + "=$$a.slice(0,$$i).concat($$a.slice($$i+1)))}" +
    "}else{" + value + "=$$c}",
    null, true
  );
}

function genRadioModel (
    el,
    value,
    modifiers
) {
  var number = modifiers && modifiers.number;
  var valueBinding = getBindingAttr(el, 'value') || 'null';
  valueBinding = number ? ("_n(" + valueBinding + ")") : valueBinding;
  addProp(el, 'checked', ("_q(" + value + "," + valueBinding + ")"));
  addHandler(el, CHECKBOX_RADIO_TOKEN, genAssignmentCode(value, valueBinding), null, true);
}

function genSelect (
    el,
    value,
    modifiers
) {
  var number = modifiers && modifiers.number;
  var selectedVal = "Array.prototype.filter" +
    ".call($event.target.options,function(o){return o.selected})" +
    ".map(function(o){var val = \"_value\" in o ? o._value : o.value;" +
    "return " + (number ? '_n(val)' : 'val') + "})";

  var assignment = '$event.target.multiple ? $$selectedVal : $$selectedVal[0]';
  var code = "var $$selectedVal = " + selectedVal + ";";
  code = code + " " + (genAssignmentCode(value, assignment));
  addHandler(el, 'change', code, null, true);
}

function genDefaultModel (
  el,
  value,
  modifiers
) {
  var type = el.attrsMap.type;
  var ref = modifiers || {};
  var lazy = ref.lazy;
  var number = ref.number;
  var trim = ref.trim;
  var needCompositionGuard = !lazy && type !== 'range';
  var event = lazy
    ? 'change'
    : type === 'range'
      ? RANGE_TOKEN
      : 'input';

  var valueExpression = '$event.target.value';
  if (trim) {
    valueExpression = "$event.target.value.trim()";
  }
  if (number) {
    valueExpression = "_n(" + valueExpression + ")";
  }

  var code = genAssignmentCode(value, valueExpression);
  if (needCompositionGuard) {
    code = "if($event.target.composing)return;" + code;
  }

  addProp(el, 'value', ("(" + value + ")"));
  addHandler(el, event, code, null, true);
  if (trim || number || type === 'number') {
    addHandler(el, 'blur', '$forceUpdate()');
  }
}

/*  */

function text (el, dir) {
  if (dir.value) {
    addProp(el, 'textContent', ("_s(" + (dir.value) + ")"));
  }
}

/*  */

function html (el, dir) {
  if (dir.value) {
    addProp(el, 'innerHTML', ("_s(" + (dir.value) + ")"));
  }
}

var directives = {
  model: model,
  text: text,
  html: html
};

/*  */

var emptyObject = Object.freeze({});

/**
 * Check if a string starts with $ or _
 */
function isReserved (str) {
  var c = (str + '').charCodeAt(0);
  return c === 0x24 || c === 0x5F
}

/**
 * Define a property.
 */
function def (obj, key, val, enumerable) {
  Object.defineProperty(obj, key, {
    value: val,
    enumerable: !!enumerable,
    writable: true,
    configurable: true
  });
}

/**
 * Parse simple path.
 */
var bailRE = /[^\w.$]/;
function parsePath (path) {
  if (bailRE.test(path)) {
    return
  }
  var segments = path.split('.');
  return function (obj) {
    for (var i = 0; i < segments.length; i++) {
      if (!obj) { return }
      obj = obj[segments[i]];
    }
    return obj
  }
}

/* not type checking this file because flow doesn't play well with Proxy */

var initProxy;

if (process.env.NODE_ENV !== 'production') {
  var allowedGlobals = makeMap(
    'Infinity,undefined,NaN,isFinite,isNaN,' +
    'parseFloat,parseInt,decodeURI,decodeURIComponent,encodeURI,encodeURIComponent,' +
    'Math,Number,Date,Array,Object,Boolean,String,RegExp,Map,Set,JSON,Intl,' +
    'require' // for Webpack/Browserify
  );

  var warnNonPresent = function (target, key) {
    warn$2(
      "Property or method \"" + key + "\" is not defined on the instance but " +
      "referenced during render. Make sure to declare reactive data " +
      "properties in the data option.",
      target
    );
  };

  var hasProxy =
    typeof Proxy !== 'undefined' &&
    Proxy.toString().match(/native code/);

  if (hasProxy) {
    var isBuiltInModifier = makeMap('stop,prevent,self,ctrl,shift,alt,meta');
    config.keyCodes = new Proxy(config.keyCodes, {
      set: function set (target, key, value) {
        if (isBuiltInModifier(key)) {
          warn$2(("Avoid overwriting built-in modifier in config.keyCodes: ." + key));
          return false
        } else {
          target[key] = value;
          return true
        }
      }
    });
  }

  var hasHandler = {
    has: function has (target, key) {
      var has = key in target;
      var isAllowed = allowedGlobals(key) || key.charAt(0) === '_';
      if (!has && !isAllowed) {
        warnNonPresent(target, key);
      }
      return has || !isAllowed
    }
  };

  var getHandler = {
    get: function get (target, key) {
      if (typeof key === 'string' && !(key in target)) {
        warnNonPresent(target, key);
      }
      return target[key]
    }
  };

  initProxy = function initProxy (vm) {
    if (hasProxy) {
      // determine which proxy handler to use
      var options = vm.$options;
      var handlers = options.render && options.render._withStripped
        ? getHandler
        : hasHandler;
      vm._renderProxy = new Proxy(vm, handlers);
    } else {
      vm._renderProxy = vm;
    }
  };
}

/*  */


var uid$1 = 0;

/**
 * A dep is an observable that can have multiple
 * directives subscribing to it.
 */
var Dep = function Dep () {
  this.id = uid$1++;
  this.subs = [];
};

Dep.prototype.addSub = function addSub (sub) {
  this.subs.push(sub);
};

Dep.prototype.removeSub = function removeSub (sub) {
  remove(this.subs, sub);
};

Dep.prototype.depend = function depend () {
  if (Dep.target) {
    Dep.target.addDep(this);
  }
};

Dep.prototype.notify = function notify () {
  // stabilize the subscriber list first
  var subs = this.subs.slice();
  for (var i = 0, l = subs.length; i < l; i++) {
    subs[i].update();
  }
};

// the current target watcher being evaluated.
// this is globally unique because there could be only one
// watcher being evaluated at any time.
Dep.target = null;
var targetStack = [];

function pushTarget (_target) {
  if (Dep.target) { targetStack.push(Dep.target); }
  Dep.target = _target;
}

function popTarget () {
  Dep.target = targetStack.pop();
}

var mark;
var measure;

if (process.env.NODE_ENV !== 'production') {
  var perf = inBrowser && window.performance;
  /* istanbul ignore if */
  if (
    perf &&
    perf.mark &&
    perf.measure &&
    perf.clearMarks &&
    perf.clearMeasures
  ) {
    mark = function (tag) { return perf.mark(tag); };
    measure = function (name, startTag, endTag) {
      perf.measure(name, startTag, endTag);
      perf.clearMarks(startTag);
      perf.clearMarks(endTag);
      perf.clearMeasures(name);
    };
  }
}

/*  */

var VNode = function VNode (
  tag,
  data,
  children,
  text,
  elm,
  context,
  componentOptions
) {
  this.tag = tag;
  this.data = data;
  this.children = children;
  this.text = text;
  this.elm = elm;
  this.ns = undefined;
  this.context = context;
  this.functionalContext = undefined;
  this.key = data && data.key;
  this.componentOptions = componentOptions;
  this.componentInstance = undefined;
  this.parent = undefined;
  this.raw = false;
  this.isStatic = false;
  this.isRootInsert = true;
  this.isComment = false;
  this.isCloned = false;
  this.isOnce = false;
};

var prototypeAccessors = { child: {} };

// DEPRECATED: alias for componentInstance for backwards compat.
/* istanbul ignore next */
prototypeAccessors.child.get = function () {
  return this.componentInstance
};

Object.defineProperties( VNode.prototype, prototypeAccessors );

var createEmptyVNode = function () {
  var node = new VNode();
  node.text = '';
  node.isComment = true;
  return node
};

function createTextVNode (val) {
  return new VNode(undefined, undefined, undefined, String(val))
}

// optimized shallow clone
// used for static nodes and slot nodes because they may be reused across
// multiple renders, cloning them avoids errors when DOM manipulations rely
// on their elm reference.
function cloneVNode (vnode) {
  var cloned = new VNode(
    vnode.tag,
    vnode.data,
    vnode.children,
    vnode.text,
    vnode.elm,
    vnode.context,
    vnode.componentOptions
  );
  cloned.ns = vnode.ns;
  cloned.isStatic = vnode.isStatic;
  cloned.key = vnode.key;
  cloned.isCloned = true;
  return cloned
}

function cloneVNodes (vnodes) {
  var len = vnodes.length;
  var res = new Array(len);
  for (var i = 0; i < len; i++) {
    res[i] = cloneVNode(vnodes[i]);
  }
  return res
}

/*
 * not type checking this file because flow doesn't play well with
 * dynamically accessing methods on Array prototype
 */

var arrayProto = Array.prototype;
var arrayMethods = Object.create(arrayProto);[
  'push',
  'pop',
  'shift',
  'unshift',
  'splice',
  'sort',
  'reverse'
]
.forEach(function (method) {
  // cache original method
  var original = arrayProto[method];
  def(arrayMethods, method, function mutator () {
    var arguments$1 = arguments;

    // avoid leaking arguments:
    // http://jsperf.com/closure-with-arguments
    var i = arguments.length;
    var args = new Array(i);
    while (i--) {
      args[i] = arguments$1[i];
    }
    var result = original.apply(this, args);
    var ob = this.__ob__;
    var inserted;
    switch (method) {
      case 'push':
        inserted = args;
        break
      case 'unshift':
        inserted = args;
        break
      case 'splice':
        inserted = args.slice(2);
        break
    }
    if (inserted) { ob.observeArray(inserted); }
    // notify change
    ob.dep.notify();
    return result
  });
});

/*  */

var arrayKeys = Object.getOwnPropertyNames(arrayMethods);

/**
 * By default, when a reactive property is set, the new value is
 * also converted to become reactive. However when passing down props,
 * we don't want to force conversion because the value may be a nested value
 * under a frozen data structure. Converting it would defeat the optimization.
 */
var observerState = {
  shouldConvert: true,
  isSettingProps: false
};

/**
 * Observer class that are attached to each observed
 * object. Once attached, the observer converts target
 * object's property keys into getter/setters that
 * collect dependencies and dispatches updates.
 */
var Observer = function Observer (value) {
  this.value = value;
  this.dep = new Dep();
  this.vmCount = 0;
  def(value, '__ob__', this);
  if (Array.isArray(value)) {
    var augment = hasProto
      ? protoAugment
      : copyAugment;
    augment(value, arrayMethods, arrayKeys);
    this.observeArray(value);
  } else {
    this.walk(value);
  }
};

/**
 * Walk through each property and convert them into
 * getter/setters. This method should only be called when
 * value type is Object.
 */
Observer.prototype.walk = function walk (obj) {
  var keys = Object.keys(obj);
  for (var i = 0; i < keys.length; i++) {
    defineReactive$$1(obj, keys[i], obj[keys[i]]);
  }
};

/**
 * Observe a list of Array items.
 */
Observer.prototype.observeArray = function observeArray (items) {
  for (var i = 0, l = items.length; i < l; i++) {
    observe(items[i]);
  }
};

// helpers

/**
 * Augment an target Object or Array by intercepting
 * the prototype chain using __proto__
 */
function protoAugment (target, src) {
  /* eslint-disable no-proto */
  target.__proto__ = src;
  /* eslint-enable no-proto */
}

/**
 * Augment an target Object or Array by defining
 * hidden properties.
 */
/* istanbul ignore next */
function copyAugment (target, src, keys) {
  for (var i = 0, l = keys.length; i < l; i++) {
    var key = keys[i];
    def(target, key, src[key]);
  }
}

/**
 * Attempt to create an observer instance for a value,
 * returns the new observer if successfully observed,
 * or the existing observer if the value already has one.
 */
function observe (value, asRootData) {
  if (!isObject(value)) {
    return
  }
  var ob;
  if (hasOwn(value, '__ob__') && value.__ob__ instanceof Observer) {
    ob = value.__ob__;
  } else if (
    observerState.shouldConvert &&
    !isServerRendering() &&
    (Array.isArray(value) || isPlainObject(value)) &&
    Object.isExtensible(value) &&
    !value._isVue
  ) {
    ob = new Observer(value);
  }
  if (asRootData && ob) {
    ob.vmCount++;
  }
  return ob
}

/**
 * Define a reactive property on an Object.
 */
function defineReactive$$1 (
  obj,
  key,
  val,
  customSetter
) {
  var dep = new Dep();

  var property = Object.getOwnPropertyDescriptor(obj, key);
  if (property && property.configurable === false) {
    return
  }

  // cater for pre-defined getter/setters
  var getter = property && property.get;
  var setter = property && property.set;

  var childOb = observe(val);
  Object.defineProperty(obj, key, {
    enumerable: true,
    configurable: true,
    get: function reactiveGetter () {
      var value = getter ? getter.call(obj) : val;
      if (Dep.target) {
        dep.depend();
        if (childOb) {
          childOb.dep.depend();
        }
        if (Array.isArray(value)) {
          dependArray(value);
        }
      }
      return value
    },
    set: function reactiveSetter (newVal) {
      var value = getter ? getter.call(obj) : val;
      /* eslint-disable no-self-compare */
      if (newVal === value || (newVal !== newVal && value !== value)) {
        return
      }
      /* eslint-enable no-self-compare */
      if (process.env.NODE_ENV !== 'production' && customSetter) {
        customSetter();
      }
      if (setter) {
        setter.call(obj, newVal);
      } else {
        val = newVal;
      }
      childOb = observe(newVal);
      dep.notify();
    }
  });
}

/**
 * Set a property on an object. Adds the new property and
 * triggers change notification if the property doesn't
 * already exist.
 */
function set (target, key, val) {
  if (Array.isArray(target) && typeof key === 'number') {
    target.length = Math.max(target.length, key);
    target.splice(key, 1, val);
    return val
  }
  if (hasOwn(target, key)) {
    target[key] = val;
    return val
  }
  var ob = (target ).__ob__;
  if (target._isVue || (ob && ob.vmCount)) {
    process.env.NODE_ENV !== 'production' && warn$2(
      'Avoid adding reactive properties to a Vue instance or its root $data ' +
      'at runtime - declare it upfront in the data option.'
    );
    return val
  }
  if (!ob) {
    target[key] = val;
    return val
  }
  defineReactive$$1(ob.value, key, val);
  ob.dep.notify();
  return val
}

/**
 * Delete a property and trigger change if necessary.
 */
function del (target, key) {
  if (Array.isArray(target) && typeof key === 'number') {
    target.splice(key, 1);
    return
  }
  var ob = (target ).__ob__;
  if (target._isVue || (ob && ob.vmCount)) {
    process.env.NODE_ENV !== 'production' && warn$2(
      'Avoid deleting properties on a Vue instance or its root $data ' +
      '- just set it to null.'
    );
    return
  }
  if (!hasOwn(target, key)) {
    return
  }
  delete target[key];
  if (!ob) {
    return
  }
  ob.dep.notify();
}

/**
 * Collect dependencies on array elements when the array is touched, since
 * we cannot intercept array element access like property getters.
 */
function dependArray (value) {
  for (var e = (void 0), i = 0, l = value.length; i < l; i++) {
    e = value[i];
    e && e.__ob__ && e.__ob__.dep.depend();
    if (Array.isArray(e)) {
      dependArray(e);
    }
  }
}

/*  */

var normalizeEvent = cached(function (name) {
  var once$$1 = name.charAt(0) === '~'; // Prefixed last, checked first
  name = once$$1 ? name.slice(1) : name;
  var capture = name.charAt(0) === '!';
  name = capture ? name.slice(1) : name;
  return {
    name: name,
    once: once$$1,
    capture: capture
  }
});

function createFnInvoker (fns) {
  function invoker () {
    var arguments$1 = arguments;

    var fns = invoker.fns;
    if (Array.isArray(fns)) {
      for (var i = 0; i < fns.length; i++) {
        fns[i].apply(null, arguments$1);
      }
    } else {
      // return handler return value for single handlers
      return fns.apply(null, arguments)
    }
  }
  invoker.fns = fns;
  return invoker
}

function updateListeners (
  on,
  oldOn,
  add,
  remove$$1,
  vm
) {
  var name, cur, old, event;
  for (name in on) {
    cur = on[name];
    old = oldOn[name];
    event = normalizeEvent(name);
    if (!cur) {
      process.env.NODE_ENV !== 'production' && warn$2(
        "Invalid handler for event \"" + (event.name) + "\": got " + String(cur),
        vm
      );
    } else if (!old) {
      if (!cur.fns) {
        cur = on[name] = createFnInvoker(cur);
      }
      add(event.name, cur, event.once, event.capture);
    } else if (cur !== old) {
      old.fns = cur;
      on[name] = old;
    }
  }
  for (name in oldOn) {
    if (!on[name]) {
      event = normalizeEvent(name);
      remove$$1(event.name, oldOn[name], event.capture);
    }
  }
}

/*  */

/*  */

// The template compiler attempts to minimize the need for normalization by
// statically analyzing the template at compile time.
//
// For plain HTML markup, normalization can be completely skipped because the
// generated render function is guaranteed to return Array<VNode>. There are
// two cases where extra normalization is needed:

// 1. When the children contains components - because a functional component
// may return an Array instead of a single root. In this case, just a simple
// normalization is needed - if any child is an Array, we flatten the whole
// thing with Array.prototype.concat. It is guaranteed to be only 1-level deep
// because functional components already normalize their own children.
function simpleNormalizeChildren (children) {
  for (var i = 0; i < children.length; i++) {
    if (Array.isArray(children[i])) {
      return Array.prototype.concat.apply([], children)
    }
  }
  return children
}

// 2. When the children contains constructs that always generated nested Arrays,
// e.g. <template>, <slot>, v-for, or when the children is provided by user
// with hand-written render functions / JSX. In such cases a full normalization
// is needed to cater to all possible types of children values.
function normalizeChildren (children) {
  return isPrimitive(children)
    ? [createTextVNode(children)]
    : Array.isArray(children)
      ? normalizeArrayChildren(children)
      : undefined
}

function normalizeArrayChildren (children, nestedIndex) {
  var res = [];
  var i, c, last;
  for (i = 0; i < children.length; i++) {
    c = children[i];
    if (c == null || typeof c === 'boolean') { continue }
    last = res[res.length - 1];
    //  nested
    if (Array.isArray(c)) {
      res.push.apply(res, normalizeArrayChildren(c, ((nestedIndex || '') + "_" + i)));
    } else if (isPrimitive(c)) {
      if (last && last.text) {
        last.text += String(c);
      } else if (c !== '') {
        // convert primitive to vnode
        res.push(createTextVNode(c));
      }
    } else {
      if (c.text && last && last.text) {
        res[res.length - 1] = createTextVNode(last.text + c.text);
      } else {
        // default key for nested array children (likely generated by v-for)
        if (c.tag && c.key == null && nestedIndex != null) {
          c.key = "__vlist" + nestedIndex + "_" + i + "__";
        }
        res.push(c);
      }
    }
  }
  return res
}

/*  */

/*  */

function initEvents (vm) {
  vm._events = Object.create(null);
  vm._hasHookEvent = false;
  // init parent attached events
  var listeners = vm.$options._parentListeners;
  if (listeners) {
    updateComponentListeners(vm, listeners);
  }
}

var target;

function add (event, fn, once$$1) {
  if (once$$1) {
    target.$once(event, fn);
  } else {
    target.$on(event, fn);
  }
}

function remove$1 (event, fn) {
  target.$off(event, fn);
}

function updateComponentListeners (
  vm,
  listeners,
  oldListeners
) {
  target = vm;
  updateListeners(listeners, oldListeners || {}, add, remove$1, vm);
}

function eventsMixin (Vue) {
  var hookRE = /^hook:/;
  Vue.prototype.$on = function (event, fn) {
    var this$1 = this;

    var vm = this;
    if (Array.isArray(event)) {
      for (var i = 0, l = event.length; i < l; i++) {
        this$1.$on(event[i], fn);
      }
    } else {
      (vm._events[event] || (vm._events[event] = [])).push(fn);
      // optimize hook:event cost by using a boolean flag marked at registration
      // instead of a hash lookup
      if (hookRE.test(event)) {
        vm._hasHookEvent = true;
      }
    }
    return vm
  };

  Vue.prototype.$once = function (event, fn) {
    var vm = this;
    function on () {
      vm.$off(event, on);
      fn.apply(vm, arguments);
    }
    on.fn = fn;
    vm.$on(event, on);
    return vm
  };

  Vue.prototype.$off = function (event, fn) {
    var this$1 = this;

    var vm = this;
    // all
    if (!arguments.length) {
      vm._events = Object.create(null);
      return vm
    }
    // array of events
    if (Array.isArray(event)) {
      for (var i$1 = 0, l = event.length; i$1 < l; i$1++) {
        this$1.$off(event[i$1], fn);
      }
      return vm
    }
    // specific event
    var cbs = vm._events[event];
    if (!cbs) {
      return vm
    }
    if (arguments.length === 1) {
      vm._events[event] = null;
      return vm
    }
    // specific handler
    var cb;
    var i = cbs.length;
    while (i--) {
      cb = cbs[i];
      if (cb === fn || cb.fn === fn) {
        cbs.splice(i, 1);
        break
      }
    }
    return vm
  };

  Vue.prototype.$emit = function (event) {
    var vm = this;
    if (process.env.NODE_ENV !== 'production') {
      var lowerCaseEvent = event.toLowerCase();
      if (lowerCaseEvent !== event && vm._events[lowerCaseEvent]) {
        tip(
          "Event \"" + lowerCaseEvent + "\" is emitted in component " +
          (formatComponentName(vm)) + " but the handler is registered for \"" + event + "\". " +
          "Note that HTML attributes are case-insensitive and you cannot use " +
          "v-on to listen to camelCase events when using in-DOM templates. " +
          "You should probably use \"" + (hyphenate(event)) + "\" instead of \"" + event + "\"."
        );
      }
    }
    var cbs = vm._events[event];
    if (cbs) {
      cbs = cbs.length > 1 ? toArray(cbs) : cbs;
      var args = toArray(arguments, 1);
      for (var i = 0, l = cbs.length; i < l; i++) {
        cbs[i].apply(vm, args);
      }
    }
    return vm
  };
}

/*  */

/**
 * Runtime helper for resolving raw children VNodes into a slot object.
 */
function resolveSlots (
  children,
  context
) {
  var slots = {};
  if (!children) {
    return slots
  }
  var defaultSlot = [];
  var name, child;
  for (var i = 0, l = children.length; i < l; i++) {
    child = children[i];
    // named slots should only be respected if the vnode was rendered in the
    // same context.
    if ((child.context === context || child.functionalContext === context) &&
        child.data && (name = child.data.slot)) {
      var slot = (slots[name] || (slots[name] = []));
      if (child.tag === 'template') {
        slot.push.apply(slot, child.children);
      } else {
        slot.push(child);
      }
    } else {
      defaultSlot.push(child);
    }
  }
  // ignore whitespace
  if (!defaultSlot.every(isWhitespace)) {
    slots.default = defaultSlot;
  }
  return slots
}

function isWhitespace (node) {
  return node.isComment || node.text === ' '
}

function resolveScopedSlots (
  fns
) {
  var res = {};
  for (var i = 0; i < fns.length; i++) {
    res[fns[i][0]] = fns[i][1];
  }
  return res
}

/*  */

var activeInstance = null;

function initLifecycle (vm) {
  var options = vm.$options;

  // locate first non-abstract parent
  var parent = options.parent;
  if (parent && !options.abstract) {
    while (parent.$options.abstract && parent.$parent) {
      parent = parent.$parent;
    }
    parent.$children.push(vm);
  }

  vm.$parent = parent;
  vm.$root = parent ? parent.$root : vm;

  vm.$children = [];
  vm.$refs = {};

  vm._watcher = null;
  vm._inactive = null;
  vm._directInactive = false;
  vm._isMounted = false;
  vm._isDestroyed = false;
  vm._isBeingDestroyed = false;
}

function lifecycleMixin (Vue) {
  Vue.prototype._update = function (vnode, hydrating) {
    var vm = this;
    if (vm._isMounted) {
      callHook(vm, 'beforeUpdate');
    }
    var prevEl = vm.$el;
    var prevVnode = vm._vnode;
    var prevActiveInstance = activeInstance;
    activeInstance = vm;
    vm._vnode = vnode;
    // Vue.prototype.__patch__ is injected in entry points
    // based on the rendering backend used.
    if (!prevVnode) {
      // initial render
      vm.$el = vm.__patch__(
        vm.$el, vnode, hydrating, false /* removeOnly */,
        vm.$options._parentElm,
        vm.$options._refElm
      );
    } else {
      // updates
      vm.$el = vm.__patch__(prevVnode, vnode);
    }
    activeInstance = prevActiveInstance;
    // update __vue__ reference
    if (prevEl) {
      prevEl.__vue__ = null;
    }
    if (vm.$el) {
      vm.$el.__vue__ = vm;
    }
    // if parent is an HOC, update its $el as well
    if (vm.$vnode && vm.$parent && vm.$vnode === vm.$parent._vnode) {
      vm.$parent.$el = vm.$el;
    }
    // updated hook is called by the scheduler to ensure that children are
    // updated in a parent's updated hook.
  };

  Vue.prototype.$forceUpdate = function () {
    var vm = this;
    if (vm._watcher) {
      vm._watcher.update();
    }
  };

  Vue.prototype.$destroy = function () {
    var vm = this;
    if (vm._isBeingDestroyed) {
      return
    }
    callHook(vm, 'beforeDestroy');
    vm._isBeingDestroyed = true;
    // remove self from parent
    var parent = vm.$parent;
    if (parent && !parent._isBeingDestroyed && !vm.$options.abstract) {
      remove(parent.$children, vm);
    }
    // teardown watchers
    if (vm._watcher) {
      vm._watcher.teardown();
    }
    var i = vm._watchers.length;
    while (i--) {
      vm._watchers[i].teardown();
    }
    // remove reference from data ob
    // frozen object may not have observer.
    if (vm._data.__ob__) {
      vm._data.__ob__.vmCount--;
    }
    // call the last hook...
    vm._isDestroyed = true;
    // invoke destroy hooks on current rendered tree
    vm.__patch__(vm._vnode, null);
    // fire destroyed hook
    callHook(vm, 'destroyed');
    // turn off all instance listeners.
    vm.$off();
    // remove __vue__ reference
    if (vm.$el) {
      vm.$el.__vue__ = null;
    }
    // remove reference to DOM nodes (prevents leak)
    vm.$options._parentElm = vm.$options._refElm = null;
  };
}



function updateChildComponent (
  vm,
  propsData,
  listeners,
  parentVnode,
  renderChildren
) {
  // determine whether component has slot children
  // we need to do this before overwriting $options._renderChildren
  var hasChildren = !!(
    renderChildren ||               // has new static slots
    vm.$options._renderChildren ||  // has old static slots
    parentVnode.data.scopedSlots || // has new scoped slots
    vm.$scopedSlots !== emptyObject // has old scoped slots
  );

  vm.$options._parentVnode = parentVnode;
  vm.$vnode = parentVnode; // update vm's placeholder node without re-render
  if (vm._vnode) { // update child tree's parent
    vm._vnode.parent = parentVnode;
  }
  vm.$options._renderChildren = renderChildren;

  // update props
  if (propsData && vm.$options.props) {
    observerState.shouldConvert = false;
    if (process.env.NODE_ENV !== 'production') {
      observerState.isSettingProps = true;
    }
    var props = vm._props;
    var propKeys = vm.$options._propKeys || [];
    for (var i = 0; i < propKeys.length; i++) {
      var key = propKeys[i];
      props[key] = validateProp(key, vm.$options.props, propsData, vm);
    }
    observerState.shouldConvert = true;
    if (process.env.NODE_ENV !== 'production') {
      observerState.isSettingProps = false;
    }
    // keep a copy of raw propsData
    vm.$options.propsData = propsData;
  }
  // update listeners
  if (listeners) {
    var oldListeners = vm.$options._parentListeners;
    vm.$options._parentListeners = listeners;
    updateComponentListeners(vm, listeners, oldListeners);
  }
  // resolve slots + force update if has children
  if (hasChildren) {
    vm.$slots = resolveSlots(renderChildren, parentVnode.context);
    vm.$forceUpdate();
  }
}

function isInInactiveTree (vm) {
  while (vm && (vm = vm.$parent)) {
    if (vm._inactive) { return true }
  }
  return false
}

function activateChildComponent (vm, direct) {
  if (direct) {
    vm._directInactive = false;
    if (isInInactiveTree(vm)) {
      return
    }
  } else if (vm._directInactive) {
    return
  }
  if (vm._inactive || vm._inactive == null) {
    vm._inactive = false;
    for (var i = 0; i < vm.$children.length; i++) {
      activateChildComponent(vm.$children[i]);
    }
    callHook(vm, 'activated');
  }
}

function deactivateChildComponent (vm, direct) {
  if (direct) {
    vm._directInactive = true;
    if (isInInactiveTree(vm)) {
      return
    }
  }
  if (!vm._inactive) {
    vm._inactive = true;
    for (var i = 0; i < vm.$children.length; i++) {
      deactivateChildComponent(vm.$children[i]);
    }
    callHook(vm, 'deactivated');
  }
}

function callHook (vm, hook) {
  var handlers = vm.$options[hook];
  if (handlers) {
    for (var i = 0, j = handlers.length; i < j; i++) {
      try {
        handlers[i].call(vm);
      } catch (e) {
        handleError(e, vm, (hook + " hook"));
      }
    }
  }
  if (vm._hasHookEvent) {
    vm.$emit('hook:' + hook);
  }
}

/*  */


var queue = [];
var has = {};
var circular = {};
var waiting = false;
var flushing = false;
var index$1 = 0;

/**
 * Reset the scheduler's state.
 */
function resetSchedulerState () {
  queue.length = 0;
  has = {};
  if (process.env.NODE_ENV !== 'production') {
    circular = {};
  }
  waiting = flushing = false;
}

/**
 * Flush both queues and run the watchers.
 */
function flushSchedulerQueue () {
  flushing = true;
  var watcher, id, vm;

  // Sort queue before flush.
  // This ensures that:
  // 1. Components are updated from parent to child. (because parent is always
  //    created before the child)
  // 2. A component's user watchers are run before its render watcher (because
  //    user watchers are created before the render watcher)
  // 3. If a component is destroyed during a parent component's watcher run,
  //    its watchers can be skipped.
  queue.sort(function (a, b) { return a.id - b.id; });

  // do not cache length because more watchers might be pushed
  // as we run existing watchers
  for (index$1 = 0; index$1 < queue.length; index$1++) {
    watcher = queue[index$1];
    id = watcher.id;
    has[id] = null;
    watcher.run();
    // in dev build, check and stop circular updates.
    if (process.env.NODE_ENV !== 'production' && has[id] != null) {
      circular[id] = (circular[id] || 0) + 1;
      if (circular[id] > config._maxUpdateCount) {
        warn$2(
          'You may have an infinite update loop ' + (
            watcher.user
              ? ("in watcher with expression \"" + (watcher.expression) + "\"")
              : "in a component render function."
          ),
          watcher.vm
        );
        break
      }
    }
  }

  // reset scheduler before updated hook called
  var oldQueue = queue.slice();
  resetSchedulerState();

  // call updated hooks
  index$1 = oldQueue.length;
  while (index$1--) {
    watcher = oldQueue[index$1];
    vm = watcher.vm;
    if (vm._watcher === watcher && vm._isMounted) {
      callHook(vm, 'updated');
    }
  }

  // devtool hook
  /* istanbul ignore if */
  if (devtools && config.devtools) {
    devtools.emit('flush');
  }
}

/**
 * Push a watcher into the watcher queue.
 * Jobs with duplicate IDs will be skipped unless it's
 * pushed when the queue is being flushed.
 */
function queueWatcher (watcher) {
  var id = watcher.id;
  if (has[id] == null) {
    has[id] = true;
    if (!flushing) {
      queue.push(watcher);
    } else {
      // if already flushing, splice the watcher based on its id
      // if already past its id, it will be run next immediately.
      var i = queue.length - 1;
      while (i >= 0 && queue[i].id > watcher.id) {
        i--;
      }
      queue.splice(Math.max(i, index$1) + 1, 0, watcher);
    }
    // queue the flush
    if (!waiting) {
      waiting = true;
      nextTick(flushSchedulerQueue);
    }
  }
}

/*  */

var uid$2 = 0;

/**
 * A watcher parses an expression, collects dependencies,
 * and fires callback when the expression value changes.
 * This is used for both the $watch() api and directives.
 */
var Watcher = function Watcher (
  vm,
  expOrFn,
  cb,
  options
) {
  this.vm = vm;
  vm._watchers.push(this);
  // options
  if (options) {
    this.deep = !!options.deep;
    this.user = !!options.user;
    this.lazy = !!options.lazy;
    this.sync = !!options.sync;
  } else {
    this.deep = this.user = this.lazy = this.sync = false;
  }
  this.cb = cb;
  this.id = ++uid$2; // uid for batching
  this.active = true;
  this.dirty = this.lazy; // for lazy watchers
  this.deps = [];
  this.newDeps = [];
  this.depIds = new _Set();
  this.newDepIds = new _Set();
  this.expression = process.env.NODE_ENV !== 'production'
    ? expOrFn.toString()
    : '';
  // parse expression for getter
  if (typeof expOrFn === 'function') {
    this.getter = expOrFn;
  } else {
    this.getter = parsePath(expOrFn);
    if (!this.getter) {
      this.getter = function () {};
      process.env.NODE_ENV !== 'production' && warn$2(
        "Failed watching path: \"" + expOrFn + "\" " +
        'Watcher only accepts simple dot-delimited paths. ' +
        'For full control, use a function instead.',
        vm
      );
    }
  }
  this.value = this.lazy
    ? undefined
    : this.get();
};

/**
 * Evaluate the getter, and re-collect dependencies.
 */
Watcher.prototype.get = function get () {
  pushTarget(this);
  var value;
  var vm = this.vm;
  if (this.user) {
    try {
      value = this.getter.call(vm, vm);
    } catch (e) {
      handleError(e, vm, ("getter for watcher \"" + (this.expression) + "\""));
    }
  } else {
    value = this.getter.call(vm, vm);
  }
  // "touch" every property so they are all tracked as
  // dependencies for deep watching
  if (this.deep) {
    traverse(value);
  }
  popTarget();
  this.cleanupDeps();
  return value
};

/**
 * Add a dependency to this directive.
 */
Watcher.prototype.addDep = function addDep (dep) {
  var id = dep.id;
  if (!this.newDepIds.has(id)) {
    this.newDepIds.add(id);
    this.newDeps.push(dep);
    if (!this.depIds.has(id)) {
      dep.addSub(this);
    }
  }
};

/**
 * Clean up for dependency collection.
 */
Watcher.prototype.cleanupDeps = function cleanupDeps () {
    var this$1 = this;

  var i = this.deps.length;
  while (i--) {
    var dep = this$1.deps[i];
    if (!this$1.newDepIds.has(dep.id)) {
      dep.removeSub(this$1);
    }
  }
  var tmp = this.depIds;
  this.depIds = this.newDepIds;
  this.newDepIds = tmp;
  this.newDepIds.clear();
  tmp = this.deps;
  this.deps = this.newDeps;
  this.newDeps = tmp;
  this.newDeps.length = 0;
};

/**
 * Subscriber interface.
 * Will be called when a dependency changes.
 */
Watcher.prototype.update = function update () {
  /* istanbul ignore else */
  if (this.lazy) {
    this.dirty = true;
  } else if (this.sync) {
    this.run();
  } else {
    queueWatcher(this);
  }
};

/**
 * Scheduler job interface.
 * Will be called by the scheduler.
 */
Watcher.prototype.run = function run () {
  if (this.active) {
    var value = this.get();
    if (
      value !== this.value ||
      // Deep watchers and watchers on Object/Arrays should fire even
      // when the value is the same, because the value may
      // have mutated.
      isObject(value) ||
      this.deep
    ) {
      // set new value
      var oldValue = this.value;
      this.value = value;
      if (this.user) {
        try {
          this.cb.call(this.vm, value, oldValue);
        } catch (e) {
          handleError(e, this.vm, ("callback for watcher \"" + (this.expression) + "\""));
        }
      } else {
        this.cb.call(this.vm, value, oldValue);
      }
    }
  }
};

/**
 * Evaluate the value of the watcher.
 * This only gets called for lazy watchers.
 */
Watcher.prototype.evaluate = function evaluate () {
  this.value = this.get();
  this.dirty = false;
};

/**
 * Depend on all deps collected by this watcher.
 */
Watcher.prototype.depend = function depend () {
    var this$1 = this;

  var i = this.deps.length;
  while (i--) {
    this$1.deps[i].depend();
  }
};

/**
 * Remove self from all dependencies' subscriber list.
 */
Watcher.prototype.teardown = function teardown () {
    var this$1 = this;

  if (this.active) {
    // remove self from vm's watcher list
    // this is a somewhat expensive operation so we skip it
    // if the vm is being destroyed.
    if (!this.vm._isBeingDestroyed) {
      remove(this.vm._watchers, this);
    }
    var i = this.deps.length;
    while (i--) {
      this$1.deps[i].removeSub(this$1);
    }
    this.active = false;
  }
};

/**
 * Recursively traverse an object to evoke all converted
 * getters, so that every nested property inside the object
 * is collected as a "deep" dependency.
 */
var seenObjects = new _Set();
function traverse (val) {
  seenObjects.clear();
  _traverse(val, seenObjects);
}

function _traverse (val, seen) {
  var i, keys;
  var isA = Array.isArray(val);
  if ((!isA && !isObject(val)) || !Object.isExtensible(val)) {
    return
  }
  if (val.__ob__) {
    var depId = val.__ob__.dep.id;
    if (seen.has(depId)) {
      return
    }
    seen.add(depId);
  }
  if (isA) {
    i = val.length;
    while (i--) { _traverse(val[i], seen); }
  } else {
    keys = Object.keys(val);
    i = keys.length;
    while (i--) { _traverse(val[keys[i]], seen); }
  }
}

/*  */

var sharedPropertyDefinition = {
  enumerable: true,
  configurable: true,
  get: noop,
  set: noop
};

function proxy (target, sourceKey, key) {
  sharedPropertyDefinition.get = function proxyGetter () {
    return this[sourceKey][key]
  };
  sharedPropertyDefinition.set = function proxySetter (val) {
    this[sourceKey][key] = val;
  };
  Object.defineProperty(target, key, sharedPropertyDefinition);
}

function initState (vm) {
  vm._watchers = [];
  var opts = vm.$options;
  if (opts.props) { initProps(vm, opts.props); }
  if (opts.methods) { initMethods(vm, opts.methods); }
  if (opts.data) {
    initData(vm);
  } else {
    observe(vm._data = {}, true /* asRootData */);
  }
  if (opts.computed) { initComputed(vm, opts.computed); }
  if (opts.watch) { initWatch(vm, opts.watch); }
}

var isReservedProp = { key: 1, ref: 1, slot: 1 };

function initProps (vm, propsOptions) {
  var propsData = vm.$options.propsData || {};
  var props = vm._props = {};
  // cache prop keys so that future props updates can iterate using Array
  // instead of dynamic object key enumeration.
  var keys = vm.$options._propKeys = [];
  var isRoot = !vm.$parent;
  // root instance props should be converted
  observerState.shouldConvert = isRoot;
  var loop = function ( key ) {
    keys.push(key);
    var value = validateProp(key, propsOptions, propsData, vm);
    /* istanbul ignore else */
    if (process.env.NODE_ENV !== 'production') {
      if (isReservedProp[key]) {
        warn$2(
          ("\"" + key + "\" is a reserved attribute and cannot be used as component prop."),
          vm
        );
      }
      defineReactive$$1(props, key, value, function () {
        if (vm.$parent && !observerState.isSettingProps) {
          warn$2(
            "Avoid mutating a prop directly since the value will be " +
            "overwritten whenever the parent component re-renders. " +
            "Instead, use a data or computed property based on the prop's " +
            "value. Prop being mutated: \"" + key + "\"",
            vm
          );
        }
      });
    } else {
      defineReactive$$1(props, key, value);
    }
    // static props are already proxied on the component's prototype
    // during Vue.extend(). We only need to proxy props defined at
    // instantiation here.
    if (!(key in vm)) {
      proxy(vm, "_props", key);
    }
  };

  for (var key in propsOptions) loop( key );
  observerState.shouldConvert = true;
}

function initData (vm) {
  var data = vm.$options.data;
  data = vm._data = typeof data === 'function'
    ? getData(data, vm)
    : data || {};
  if (!isPlainObject(data)) {
    data = {};
    process.env.NODE_ENV !== 'production' && warn$2(
      'data functions should return an object:\n' +
      'https://vuejs.org/v2/guide/components.html#data-Must-Be-a-Function',
      vm
    );
  }
  // proxy data on instance
  var keys = Object.keys(data);
  var props = vm.$options.props;
  var i = keys.length;
  while (i--) {
    if (props && hasOwn(props, keys[i])) {
      process.env.NODE_ENV !== 'production' && warn$2(
        "The data property \"" + (keys[i]) + "\" is already declared as a prop. " +
        "Use prop default value instead.",
        vm
      );
    } else if (!isReserved(keys[i])) {
      proxy(vm, "_data", keys[i]);
    }
  }
  // observe data
  observe(data, true /* asRootData */);
}

function getData (data, vm) {
  try {
    return data.call(vm)
  } catch (e) {
    handleError(e, vm, "data()");
    return {}
  }
}

var computedWatcherOptions = { lazy: true };

function initComputed (vm, computed) {
  var watchers = vm._computedWatchers = Object.create(null);

  for (var key in computed) {
    var userDef = computed[key];
    var getter = typeof userDef === 'function' ? userDef : userDef.get;
    if (process.env.NODE_ENV !== 'production') {
      if (getter === undefined) {
        warn$2(
          ("No getter function has been defined for computed property \"" + key + "\"."),
          vm
        );
        getter = noop;
      }
    }
    // create internal watcher for the computed property.
    watchers[key] = new Watcher(vm, getter, noop, computedWatcherOptions);

    // component-defined computed properties are already defined on the
    // component prototype. We only need to define computed properties defined
    // at instantiation here.
    if (!(key in vm)) {
      defineComputed(vm, key, userDef);
    }
  }
}

function defineComputed (target, key, userDef) {
  if (typeof userDef === 'function') {
    sharedPropertyDefinition.get = createComputedGetter(key);
    sharedPropertyDefinition.set = noop;
  } else {
    sharedPropertyDefinition.get = userDef.get
      ? userDef.cache !== false
        ? createComputedGetter(key)
        : userDef.get
      : noop;
    sharedPropertyDefinition.set = userDef.set
      ? userDef.set
      : noop;
  }
  Object.defineProperty(target, key, sharedPropertyDefinition);
}

function createComputedGetter (key) {
  return function computedGetter () {
    var watcher = this._computedWatchers && this._computedWatchers[key];
    if (watcher) {
      if (watcher.dirty) {
        watcher.evaluate();
      }
      if (Dep.target) {
        watcher.depend();
      }
      return watcher.value
    }
  }
}

function initMethods (vm, methods) {
  var props = vm.$options.props;
  for (var key in methods) {
    vm[key] = methods[key] == null ? noop : bind(methods[key], vm);
    if (process.env.NODE_ENV !== 'production') {
      if (methods[key] == null) {
        warn$2(
          "method \"" + key + "\" has an undefined value in the component definition. " +
          "Did you reference the function correctly?",
          vm
        );
      }
      if (props && hasOwn(props, key)) {
        warn$2(
          ("method \"" + key + "\" has already been defined as a prop."),
          vm
        );
      }
    }
  }
}

function initWatch (vm, watch) {
  for (var key in watch) {
    var handler = watch[key];
    if (Array.isArray(handler)) {
      for (var i = 0; i < handler.length; i++) {
        createWatcher(vm, key, handler[i]);
      }
    } else {
      createWatcher(vm, key, handler);
    }
  }
}

function createWatcher (vm, key, handler) {
  var options;
  if (isPlainObject(handler)) {
    options = handler;
    handler = handler.handler;
  }
  if (typeof handler === 'string') {
    handler = vm[handler];
  }
  vm.$watch(key, handler, options);
}

function stateMixin (Vue) {
  // flow somehow has problems with directly declared definition object
  // when using Object.defineProperty, so we have to procedurally build up
  // the object here.
  var dataDef = {};
  dataDef.get = function () { return this._data };
  var propsDef = {};
  propsDef.get = function () { return this._props };
  if (process.env.NODE_ENV !== 'production') {
    dataDef.set = function (newData) {
      warn$2(
        'Avoid replacing instance root $data. ' +
        'Use nested data properties instead.',
        this
      );
    };
    propsDef.set = function () {
      warn$2("$props is readonly.", this);
    };
  }
  Object.defineProperty(Vue.prototype, '$data', dataDef);
  Object.defineProperty(Vue.prototype, '$props', propsDef);

  Vue.prototype.$set = set;
  Vue.prototype.$delete = del;

  Vue.prototype.$watch = function (
    expOrFn,
    cb,
    options
  ) {
    var vm = this;
    options = options || {};
    options.user = true;
    var watcher = new Watcher(vm, expOrFn, cb, options);
    if (options.immediate) {
      cb.call(vm, watcher.value);
    }
    return function unwatchFn () {
      watcher.teardown();
    }
  };
}

/*  */

// hooks to be invoked on component VNodes during patch
var componentVNodeHooks = {
  init: function init (
    vnode,
    hydrating,
    parentElm,
    refElm
  ) {
    if (!vnode.componentInstance || vnode.componentInstance._isDestroyed) {
      var child = vnode.componentInstance = createComponentInstanceForVnode(
        vnode,
        activeInstance,
        parentElm,
        refElm
      );
      child.$mount(hydrating ? vnode.elm : undefined, hydrating);
    } else if (vnode.data.keepAlive) {
      // kept-alive components, treat as a patch
      var mountedNode = vnode; // work around flow
      componentVNodeHooks.prepatch(mountedNode, mountedNode);
    }
  },

  prepatch: function prepatch (oldVnode, vnode) {
    var options = vnode.componentOptions;
    var child = vnode.componentInstance = oldVnode.componentInstance;
    updateChildComponent(
      child,
      options.propsData, // updated props
      options.listeners, // updated listeners
      vnode, // new parent vnode
      options.children // new children
    );
  },

  insert: function insert (vnode) {
    if (!vnode.componentInstance._isMounted) {
      vnode.componentInstance._isMounted = true;
      callHook(vnode.componentInstance, 'mounted');
    }
    if (vnode.data.keepAlive) {
      activateChildComponent(vnode.componentInstance, true /* direct */);
    }
  },

  destroy: function destroy (vnode) {
    if (!vnode.componentInstance._isDestroyed) {
      if (!vnode.data.keepAlive) {
        vnode.componentInstance.$destroy();
      } else {
        deactivateChildComponent(vnode.componentInstance, true /* direct */);
      }
    }
  }
};

var hooksToMerge = Object.keys(componentVNodeHooks);

function createComponent (
  Ctor,
  data,
  context,
  children,
  tag
) {
  if (!Ctor) {
    return
  }

  var baseCtor = context.$options._base;
  if (isObject(Ctor)) {
    Ctor = baseCtor.extend(Ctor);
  }

  if (typeof Ctor !== 'function') {
    if (process.env.NODE_ENV !== 'production') {
      warn$2(("Invalid Component definition: " + (String(Ctor))), context);
    }
    return
  }

  // async component
  if (!Ctor.cid) {
    if (Ctor.resolved) {
      Ctor = Ctor.resolved;
    } else {
      Ctor = resolveAsyncComponent(Ctor, baseCtor, function () {
        // it's ok to queue this on every render because
        // $forceUpdate is buffered by the scheduler.
        context.$forceUpdate();
      });
      if (!Ctor) {
        // return nothing if this is indeed an async component
        // wait for the callback to trigger parent update.
        return
      }
    }
  }

  // resolve constructor options in case global mixins are applied after
  // component constructor creation
  resolveConstructorOptions(Ctor);

  data = data || {};

  // transform component v-model data into props & events
  if (data.model) {
    transformModel(Ctor.options, data);
  }

  // extract props
  var propsData = extractProps(data, Ctor, tag);

  // functional component
  if (Ctor.options.functional) {
    return createFunctionalComponent(Ctor, propsData, data, context, children)
  }

  // extract listeners, since these needs to be treated as
  // child component listeners instead of DOM listeners
  var listeners = data.on;
  // replace with listeners with .native modifier
  data.on = data.nativeOn;

  if (Ctor.options.abstract) {
    // abstract components do not keep anything
    // other than props & listeners
    data = {};
  }

  // merge component management hooks onto the placeholder node
  mergeHooks(data);

  // return a placeholder vnode
  var name = Ctor.options.name || tag;
  var vnode = new VNode(
    ("vue-component-" + (Ctor.cid) + (name ? ("-" + name) : '')),
    data, undefined, undefined, undefined, context,
    { Ctor: Ctor, propsData: propsData, listeners: listeners, tag: tag, children: children }
  );
  return vnode
}

function createFunctionalComponent (
  Ctor,
  propsData,
  data,
  context,
  children
) {
  var props = {};
  var propOptions = Ctor.options.props;
  if (propOptions) {
    for (var key in propOptions) {
      props[key] = validateProp(key, propOptions, propsData);
    }
  }
  // ensure the createElement function in functional components
  // gets a unique context - this is necessary for correct named slot check
  var _context = Object.create(context);
  var h = function (a, b, c, d) { return createElement(_context, a, b, c, d, true); };
  var vnode = Ctor.options.render.call(null, h, {
    props: props,
    data: data,
    parent: context,
    children: children,
    slots: function () { return resolveSlots(children, context); }
  });
  if (vnode instanceof VNode) {
    vnode.functionalContext = context;
    if (data.slot) {
      (vnode.data || (vnode.data = {})).slot = data.slot;
    }
  }
  return vnode
}

function createComponentInstanceForVnode (
  vnode, // we know it's MountedComponentVNode but flow doesn't
  parent, // activeInstance in lifecycle state
  parentElm,
  refElm
) {
  var vnodeComponentOptions = vnode.componentOptions;
  var options = {
    _isComponent: true,
    parent: parent,
    propsData: vnodeComponentOptions.propsData,
    _componentTag: vnodeComponentOptions.tag,
    _parentVnode: vnode,
    _parentListeners: vnodeComponentOptions.listeners,
    _renderChildren: vnodeComponentOptions.children,
    _parentElm: parentElm || null,
    _refElm: refElm || null
  };
  // check inline-template render functions
  var inlineTemplate = vnode.data.inlineTemplate;
  if (inlineTemplate) {
    options.render = inlineTemplate.render;
    options.staticRenderFns = inlineTemplate.staticRenderFns;
  }
  return new vnodeComponentOptions.Ctor(options)
}

function resolveAsyncComponent (
  factory,
  baseCtor,
  cb
) {
  if (factory.requested) {
    // pool callbacks
    factory.pendingCallbacks.push(cb);
  } else {
    factory.requested = true;
    var cbs = factory.pendingCallbacks = [cb];
    var sync = true;

    var resolve = function (res) {
      if (isObject(res)) {
        res = baseCtor.extend(res);
      }
      // cache resolved
      factory.resolved = res;
      // invoke callbacks only if this is not a synchronous resolve
      // (async resolves are shimmed as synchronous during SSR)
      if (!sync) {
        for (var i = 0, l = cbs.length; i < l; i++) {
          cbs[i](res);
        }
      }
    };

    var reject = function (reason) {
      process.env.NODE_ENV !== 'production' && warn$2(
        "Failed to resolve async component: " + (String(factory)) +
        (reason ? ("\nReason: " + reason) : '')
      );
    };

    var res = factory(resolve, reject);

    // handle promise
    if (res && typeof res.then === 'function' && !factory.resolved) {
      res.then(resolve, reject);
    }

    sync = false;
    // return in case resolved synchronously
    return factory.resolved
  }
}

function extractProps (data, Ctor, tag) {
  // we are only extracting raw values here.
  // validation and default values are handled in the child
  // component itself.
  var propOptions = Ctor.options.props;
  if (!propOptions) {
    return
  }
  var res = {};
  var attrs = data.attrs;
  var props = data.props;
  var domProps = data.domProps;
  if (attrs || props || domProps) {
    for (var key in propOptions) {
      var altKey = hyphenate(key);
      if (process.env.NODE_ENV !== 'production') {
        var keyInLowerCase = key.toLowerCase();
        if (
          key !== keyInLowerCase &&
          attrs && attrs.hasOwnProperty(keyInLowerCase)
        ) {
          tip(
            "Prop \"" + keyInLowerCase + "\" is passed to component " +
            (formatComponentName(tag || Ctor)) + ", but the declared prop name is" +
            " \"" + key + "\". " +
            "Note that HTML attributes are case-insensitive and camelCased " +
            "props need to use their kebab-case equivalents when using in-DOM " +
            "templates. You should probably use \"" + altKey + "\" instead of \"" + key + "\"."
          );
        }
      }
      checkProp(res, props, key, altKey, true) ||
      checkProp(res, attrs, key, altKey) ||
      checkProp(res, domProps, key, altKey);
    }
  }
  return res
}

function checkProp (
  res,
  hash,
  key,
  altKey,
  preserve
) {
  if (hash) {
    if (hasOwn(hash, key)) {
      res[key] = hash[key];
      if (!preserve) {
        delete hash[key];
      }
      return true
    } else if (hasOwn(hash, altKey)) {
      res[key] = hash[altKey];
      if (!preserve) {
        delete hash[altKey];
      }
      return true
    }
  }
  return false
}

function mergeHooks (data) {
  if (!data.hook) {
    data.hook = {};
  }
  for (var i = 0; i < hooksToMerge.length; i++) {
    var key = hooksToMerge[i];
    var fromParent = data.hook[key];
    var ours = componentVNodeHooks[key];
    data.hook[key] = fromParent ? mergeHook$1(ours, fromParent) : ours;
  }
}

function mergeHook$1 (one, two) {
  return function (a, b, c, d) {
    one(a, b, c, d);
    two(a, b, c, d);
  }
}

// transform component v-model info (value and callback) into
// prop and event handler respectively.
function transformModel (options, data) {
  var prop = (options.model && options.model.prop) || 'value';
  var event = (options.model && options.model.event) || 'input';(data.props || (data.props = {}))[prop] = data.model.value;
  var on = data.on || (data.on = {});
  if (on[event]) {
    on[event] = [data.model.callback].concat(on[event]);
  } else {
    on[event] = data.model.callback;
  }
}

/*  */

var SIMPLE_NORMALIZE = 1;
var ALWAYS_NORMALIZE = 2;

// wrapper function for providing a more flexible interface
// without getting yelled at by flow
function createElement (
  context,
  tag,
  data,
  children,
  normalizationType,
  alwaysNormalize
) {
  if (Array.isArray(data) || isPrimitive(data)) {
    normalizationType = children;
    children = data;
    data = undefined;
  }
  if (alwaysNormalize) { normalizationType = ALWAYS_NORMALIZE; }
  return _createElement(context, tag, data, children, normalizationType)
}

function _createElement (
  context,
  tag,
  data,
  children,
  normalizationType
) {
  if (data && data.__ob__) {
    process.env.NODE_ENV !== 'production' && warn$2(
      "Avoid using observed data object as vnode data: " + (JSON.stringify(data)) + "\n" +
      'Always create fresh vnode data objects in each render!',
      context
    );
    return createEmptyVNode()
  }
  if (!tag) {
    // in case of component :is set to falsy value
    return createEmptyVNode()
  }
  // support single function children as default scoped slot
  if (Array.isArray(children) &&
      typeof children[0] === 'function') {
    data = data || {};
    data.scopedSlots = { default: children[0] };
    children.length = 0;
  }
  if (normalizationType === ALWAYS_NORMALIZE) {
    children = normalizeChildren(children);
  } else if (normalizationType === SIMPLE_NORMALIZE) {
    children = simpleNormalizeChildren(children);
  }
  var vnode, ns;
  if (typeof tag === 'string') {
    var Ctor;
    ns = config.getTagNamespace(tag);
    if (config.isReservedTag(tag)) {
      // platform built-in elements
      vnode = new VNode(
        config.parsePlatformTagName(tag), data, children,
        undefined, undefined, context
      );
    } else if ((Ctor = resolveAsset(context.$options, 'components', tag))) {
      // component
      vnode = createComponent(Ctor, data, context, children, tag);
    } else {
      // unknown or unlisted namespaced elements
      // check at runtime because it may get assigned a namespace when its
      // parent normalizes children
      vnode = new VNode(
        tag, data, children,
        undefined, undefined, context
      );
    }
  } else {
    // direct component options / constructor
    vnode = createComponent(tag, data, context, children);
  }
  if (vnode) {
    if (ns) { applyNS(vnode, ns); }
    return vnode
  } else {
    return createEmptyVNode()
  }
}

function applyNS (vnode, ns) {
  vnode.ns = ns;
  if (vnode.tag === 'foreignObject') {
    // use default namespace inside foreignObject
    return
  }
  if (vnode.children) {
    for (var i = 0, l = vnode.children.length; i < l; i++) {
      var child = vnode.children[i];
      if (child.tag && !child.ns) {
        applyNS(child, ns);
      }
    }
  }
}

/*  */

/**
 * Runtime helper for rendering v-for lists.
 */
function renderList (
  val,
  render
) {
  var ret, i, l, keys, key;
  if (Array.isArray(val) || typeof val === 'string') {
    ret = new Array(val.length);
    for (i = 0, l = val.length; i < l; i++) {
      ret[i] = render(val[i], i);
    }
  } else if (typeof val === 'number') {
    ret = new Array(val);
    for (i = 0; i < val; i++) {
      ret[i] = render(i + 1, i);
    }
  } else if (isObject(val)) {
    keys = Object.keys(val);
    ret = new Array(keys.length);
    for (i = 0, l = keys.length; i < l; i++) {
      key = keys[i];
      ret[i] = render(val[key], key, i);
    }
  }
  return ret
}

/*  */

/**
 * Runtime helper for rendering <slot>
 */
function renderSlot (
  name,
  fallback,
  props,
  bindObject
) {
  var scopedSlotFn = this.$scopedSlots[name];
  if (scopedSlotFn) { // scoped slot
    props = props || {};
    if (bindObject) {
      extend(props, bindObject);
    }
    return scopedSlotFn(props) || fallback
  } else {
    var slotNodes = this.$slots[name];
    // warn duplicate slot usage
    if (slotNodes && process.env.NODE_ENV !== 'production') {
      slotNodes._rendered && warn$2(
        "Duplicate presence of slot \"" + name + "\" found in the same render tree " +
        "- this will likely cause render errors.",
        this
      );
      slotNodes._rendered = true;
    }
    return slotNodes || fallback
  }
}

/*  */

/**
 * Runtime helper for resolving filters
 */
function resolveFilter (id) {
  return resolveAsset(this.$options, 'filters', id, true) || identity
}

/*  */

/**
 * Runtime helper for checking keyCodes from config.
 */
function checkKeyCodes (
  eventKeyCode,
  key,
  builtInAlias
) {
  var keyCodes = config.keyCodes[key] || builtInAlias;
  if (Array.isArray(keyCodes)) {
    return keyCodes.indexOf(eventKeyCode) === -1
  } else {
    return keyCodes !== eventKeyCode
  }
}

/*  */

/**
 * Runtime helper for merging v-bind="object" into a VNode's data.
 */
function bindObjectProps (
  data,
  tag,
  value,
  asProp
) {
  if (value) {
    if (!isObject(value)) {
      process.env.NODE_ENV !== 'production' && warn$2(
        'v-bind without argument expects an Object or Array value',
        this
      );
    } else {
      if (Array.isArray(value)) {
        value = toObject(value);
      }
      var hash;
      for (var key in value) {
        if (key === 'class' || key === 'style') {
          hash = data;
        } else {
          var type = data.attrs && data.attrs.type;
          hash = asProp || config.mustUseProp(tag, type, key)
            ? data.domProps || (data.domProps = {})
            : data.attrs || (data.attrs = {});
        }
        if (!(key in hash)) {
          hash[key] = value[key];
        }
      }
    }
  }
  return data
}

/*  */

/**
 * Runtime helper for rendering static trees.
 */
function renderStatic (
  index,
  isInFor
) {
  var tree = this._staticTrees[index];
  // if has already-rendered static tree and not inside v-for,
  // we can reuse the same tree by doing a shallow clone.
  if (tree && !isInFor) {
    return Array.isArray(tree)
      ? cloneVNodes(tree)
      : cloneVNode(tree)
  }
  // otherwise, render a fresh tree.
  tree = this._staticTrees[index] =
    this.$options.staticRenderFns[index].call(this._renderProxy);
  markStatic$1(tree, ("__static__" + index), false);
  return tree
}

/**
 * Runtime helper for v-once.
 * Effectively it means marking the node as static with a unique key.
 */
function markOnce (
  tree,
  index,
  key
) {
  markStatic$1(tree, ("__once__" + index + (key ? ("_" + key) : "")), true);
  return tree
}

function markStatic$1 (
  tree,
  key,
  isOnce
) {
  if (Array.isArray(tree)) {
    for (var i = 0; i < tree.length; i++) {
      if (tree[i] && typeof tree[i] !== 'string') {
        markStaticNode(tree[i], (key + "_" + i), isOnce);
      }
    }
  } else {
    markStaticNode(tree, key, isOnce);
  }
}

function markStaticNode (node, key, isOnce) {
  node.isStatic = true;
  node.key = key;
  node.isOnce = isOnce;
}

/*  */

function initRender (vm) {
  vm.$vnode = null; // the placeholder node in parent tree
  vm._vnode = null; // the root of the child tree
  vm._staticTrees = null;
  var parentVnode = vm.$options._parentVnode;
  var renderContext = parentVnode && parentVnode.context;
  vm.$slots = resolveSlots(vm.$options._renderChildren, renderContext);
  vm.$scopedSlots = emptyObject;
  // bind the createElement fn to this instance
  // so that we get proper render context inside it.
  // args order: tag, data, children, normalizationType, alwaysNormalize
  // internal version is used by render functions compiled from templates
  vm._c = function (a, b, c, d) { return createElement(vm, a, b, c, d, false); };
  // normalization is always applied for the public version, used in
  // user-written render functions.
  vm.$createElement = function (a, b, c, d) { return createElement(vm, a, b, c, d, true); };
}

function renderMixin (Vue) {
  Vue.prototype.$nextTick = function (fn) {
    return nextTick(fn, this)
  };

  Vue.prototype._render = function () {
    var vm = this;
    var ref = vm.$options;
    var render = ref.render;
    var staticRenderFns = ref.staticRenderFns;
    var _parentVnode = ref._parentVnode;

    if (vm._isMounted) {
      // clone slot nodes on re-renders
      for (var key in vm.$slots) {
        vm.$slots[key] = cloneVNodes(vm.$slots[key]);
      }
    }

    vm.$scopedSlots = (_parentVnode && _parentVnode.data.scopedSlots) || emptyObject;

    if (staticRenderFns && !vm._staticTrees) {
      vm._staticTrees = [];
    }
    // set parent vnode. this allows render functions to have access
    // to the data on the placeholder node.
    vm.$vnode = _parentVnode;
    // render self
    var vnode;
    try {
      vnode = render.call(vm._renderProxy, vm.$createElement);
    } catch (e) {
      handleError(e, vm, "render function");
      // return error render result,
      // or previous vnode to prevent render error causing blank component
      /* istanbul ignore else */
      if (process.env.NODE_ENV !== 'production') {
        vnode = vm.$options.renderError
          ? vm.$options.renderError.call(vm._renderProxy, vm.$createElement, e)
          : vm._vnode;
      } else {
        vnode = vm._vnode;
      }
    }
    // return empty vnode in case the render function errored out
    if (!(vnode instanceof VNode)) {
      if (process.env.NODE_ENV !== 'production' && Array.isArray(vnode)) {
        warn$2(
          'Multiple root nodes returned from render function. Render function ' +
          'should return a single root node.',
          vm
        );
      }
      vnode = createEmptyVNode();
    }
    // set parent
    vnode.parent = _parentVnode;
    return vnode
  };

  // internal render helpers.
  // these are exposed on the instance prototype to reduce generated render
  // code size.
  Vue.prototype._o = markOnce;
  Vue.prototype._n = toNumber;
  Vue.prototype._s = _toString;
  Vue.prototype._l = renderList;
  Vue.prototype._t = renderSlot;
  Vue.prototype._q = looseEqual;
  Vue.prototype._i = looseIndexOf;
  Vue.prototype._m = renderStatic;
  Vue.prototype._f = resolveFilter;
  Vue.prototype._k = checkKeyCodes;
  Vue.prototype._b = bindObjectProps;
  Vue.prototype._v = createTextVNode;
  Vue.prototype._e = createEmptyVNode;
  Vue.prototype._u = resolveScopedSlots;
}

/*  */

function initProvide (vm) {
  var provide = vm.$options.provide;
  if (provide) {
    vm._provided = typeof provide === 'function'
      ? provide.call(vm)
      : provide;
  }
}

function initInjections (vm) {
  var inject = vm.$options.inject;
  if (inject) {
    // inject is :any because flow is not smart enough to figure out cached
    // isArray here
    var isArray = Array.isArray(inject);
    var keys = isArray
      ? inject
      : hasSymbol
        ? Reflect.ownKeys(inject)
        : Object.keys(inject);

    var loop = function ( i ) {
      var key = keys[i];
      var provideKey = isArray ? key : inject[key];
      var source = vm;
      while (source) {
        if (source._provided && provideKey in source._provided) {
          /* istanbul ignore else */
          if (process.env.NODE_ENV !== 'production') {
            defineReactive$$1(vm, key, source._provided[provideKey], function () {
              warn$2(
                "Avoid mutating an injected value directly since the changes will be " +
                "overwritten whenever the provided component re-renders. " +
                "injection being mutated: \"" + key + "\"",
                vm
              );
            });
          } else {
            defineReactive$$1(vm, key, source._provided[provideKey]);
          }
          break
        }
        source = source.$parent;
      }
    };

    for (var i = 0; i < keys.length; i++) loop( i );
  }
}

/*  */

var uid = 0;

function initMixin (Vue) {
  Vue.prototype._init = function (options) {
    var vm = this;
    // a uid
    vm._uid = uid++;

    var startTag, endTag;
    /* istanbul ignore if */
    if (process.env.NODE_ENV !== 'production' && config.performance && mark) {
      startTag = "vue-perf-init:" + (vm._uid);
      endTag = "vue-perf-end:" + (vm._uid);
      mark(startTag);
    }

    // a flag to avoid this being observed
    vm._isVue = true;
    // merge options
    if (options && options._isComponent) {
      // optimize internal component instantiation
      // since dynamic options merging is pretty slow, and none of the
      // internal component options needs special treatment.
      initInternalComponent(vm, options);
    } else {
      vm.$options = mergeOptions(
        resolveConstructorOptions(vm.constructor),
        options || {},
        vm
      );
    }
    /* istanbul ignore else */
    if (process.env.NODE_ENV !== 'production') {
      initProxy(vm);
    } else {
      vm._renderProxy = vm;
    }
    // expose real self
    vm._self = vm;
    initLifecycle(vm);
    initEvents(vm);
    initRender(vm);
    callHook(vm, 'beforeCreate');
    initInjections(vm); // resolve injections before data/props
    initState(vm);
    initProvide(vm); // resolve provide after data/props
    callHook(vm, 'created');

    /* istanbul ignore if */
    if (process.env.NODE_ENV !== 'production' && config.performance && mark) {
      vm._name = formatComponentName(vm, false);
      mark(endTag);
      measure(((vm._name) + " init"), startTag, endTag);
    }

    if (vm.$options.el) {
      vm.$mount(vm.$options.el);
    }
  };
}

function initInternalComponent (vm, options) {
  var opts = vm.$options = Object.create(vm.constructor.options);
  // doing this because it's faster than dynamic enumeration.
  opts.parent = options.parent;
  opts.propsData = options.propsData;
  opts._parentVnode = options._parentVnode;
  opts._parentListeners = options._parentListeners;
  opts._renderChildren = options._renderChildren;
  opts._componentTag = options._componentTag;
  opts._parentElm = options._parentElm;
  opts._refElm = options._refElm;
  if (options.render) {
    opts.render = options.render;
    opts.staticRenderFns = options.staticRenderFns;
  }
}

function resolveConstructorOptions (Ctor) {
  var options = Ctor.options;
  if (Ctor.super) {
    var superOptions = resolveConstructorOptions(Ctor.super);
    var cachedSuperOptions = Ctor.superOptions;
    if (superOptions !== cachedSuperOptions) {
      // super option changed,
      // need to resolve new options.
      Ctor.superOptions = superOptions;
      // check if there are any late-modified/attached options (#4976)
      var modifiedOptions = resolveModifiedOptions(Ctor);
      // update base extend options
      if (modifiedOptions) {
        extend(Ctor.extendOptions, modifiedOptions);
      }
      options = Ctor.options = mergeOptions(superOptions, Ctor.extendOptions);
      if (options.name) {
        options.components[options.name] = Ctor;
      }
    }
  }
  return options
}

function resolveModifiedOptions (Ctor) {
  var modified;
  var latest = Ctor.options;
  var sealed = Ctor.sealedOptions;
  for (var key in latest) {
    if (latest[key] !== sealed[key]) {
      if (!modified) { modified = {}; }
      modified[key] = dedupe(latest[key], sealed[key]);
    }
  }
  return modified
}

function dedupe (latest, sealed) {
  // compare latest and sealed to ensure lifecycle hooks won't be duplicated
  // between merges
  if (Array.isArray(latest)) {
    var res = [];
    sealed = Array.isArray(sealed) ? sealed : [sealed];
    for (var i = 0; i < latest.length; i++) {
      if (sealed.indexOf(latest[i]) < 0) {
        res.push(latest[i]);
      }
    }
    return res
  } else {
    return latest
  }
}

function Vue (options) {
  if (process.env.NODE_ENV !== 'production' &&
    !(this instanceof Vue)) {
    warn$2('Vue is a constructor and should be called with the `new` keyword');
  }
  this._init(options);
}

initMixin(Vue);
stateMixin(Vue);
eventsMixin(Vue);
lifecycleMixin(Vue);
renderMixin(Vue);

/*  */

/**
 * Option overwriting strategies are functions that handle
 * how to merge a parent option value and a child option
 * value into the final value.
 */
var strats = config.optionMergeStrategies;

/**
 * Options with restrictions
 */
if (process.env.NODE_ENV !== 'production') {
  strats.el = strats.propsData = function (parent, child, vm, key) {
    if (!vm) {
      warn$2(
        "option \"" + key + "\" can only be used during instance " +
        'creation with the `new` keyword.'
      );
    }
    return defaultStrat(parent, child)
  };
}

/**
 * Helper that recursively merges two data objects together.
 */
function mergeData (to, from) {
  if (!from) { return to }
  var key, toVal, fromVal;
  var keys = Object.keys(from);
  for (var i = 0; i < keys.length; i++) {
    key = keys[i];
    toVal = to[key];
    fromVal = from[key];
    if (!hasOwn(to, key)) {
      set(to, key, fromVal);
    } else if (isPlainObject(toVal) && isPlainObject(fromVal)) {
      mergeData(toVal, fromVal);
    }
  }
  return to
}

/**
 * Data
 */
strats.data = function (
  parentVal,
  childVal,
  vm
) {
  if (!vm) {
    // in a Vue.extend merge, both should be functions
    if (!childVal) {
      return parentVal
    }
    if (typeof childVal !== 'function') {
      process.env.NODE_ENV !== 'production' && warn$2(
        'The "data" option should be a function ' +
        'that returns a per-instance value in component ' +
        'definitions.',
        vm
      );
      return parentVal
    }
    if (!parentVal) {
      return childVal
    }
    // when parentVal & childVal are both present,
    // we need to return a function that returns the
    // merged result of both functions... no need to
    // check if parentVal is a function here because
    // it has to be a function to pass previous merges.
    return function mergedDataFn () {
      return mergeData(
        childVal.call(this),
        parentVal.call(this)
      )
    }
  } else if (parentVal || childVal) {
    return function mergedInstanceDataFn () {
      // instance merge
      var instanceData = typeof childVal === 'function'
        ? childVal.call(vm)
        : childVal;
      var defaultData = typeof parentVal === 'function'
        ? parentVal.call(vm)
        : undefined;
      if (instanceData) {
        return mergeData(instanceData, defaultData)
      } else {
        return defaultData
      }
    }
  }
};

/**
 * Hooks and props are merged as arrays.
 */
function mergeHook (
  parentVal,
  childVal
) {
  return childVal
    ? parentVal
      ? parentVal.concat(childVal)
      : Array.isArray(childVal)
        ? childVal
        : [childVal]
    : parentVal
}

config._lifecycleHooks.forEach(function (hook) {
  strats[hook] = mergeHook;
});

/**
 * Assets
 *
 * When a vm is present (instance creation), we need to do
 * a three-way merge between constructor options, instance
 * options and parent options.
 */
function mergeAssets (parentVal, childVal) {
  var res = Object.create(parentVal || null);
  return childVal
    ? extend(res, childVal)
    : res
}

config._assetTypes.forEach(function (type) {
  strats[type + 's'] = mergeAssets;
});

/**
 * Watchers.
 *
 * Watchers hashes should not overwrite one
 * another, so we merge them as arrays.
 */
strats.watch = function (parentVal, childVal) {
  /* istanbul ignore if */
  if (!childVal) { return Object.create(parentVal || null) }
  if (!parentVal) { return childVal }
  var ret = {};
  extend(ret, parentVal);
  for (var key in childVal) {
    var parent = ret[key];
    var child = childVal[key];
    if (parent && !Array.isArray(parent)) {
      parent = [parent];
    }
    ret[key] = parent
      ? parent.concat(child)
      : [child];
  }
  return ret
};

/**
 * Other object hashes.
 */
strats.props =
strats.methods =
strats.computed = function (parentVal, childVal) {
  if (!childVal) { return Object.create(parentVal || null) }
  if (!parentVal) { return childVal }
  var ret = Object.create(null);
  extend(ret, parentVal);
  extend(ret, childVal);
  return ret
};

/**
 * Default strategy.
 */
var defaultStrat = function (parentVal, childVal) {
  return childVal === undefined
    ? parentVal
    : childVal
};

/**
 * Validate component names
 */
function checkComponents (options) {
  for (var key in options.components) {
    var lower = key.toLowerCase();
    if (isBuiltInTag(lower) || config.isReservedTag(lower)) {
      warn$2(
        'Do not use built-in or reserved HTML elements as component ' +
        'id: ' + key
      );
    }
  }
}

/**
 * Ensure all props option syntax are normalized into the
 * Object-based format.
 */
function normalizeProps (options) {
  var props = options.props;
  if (!props) { return }
  var res = {};
  var i, val, name;
  if (Array.isArray(props)) {
    i = props.length;
    while (i--) {
      val = props[i];
      if (typeof val === 'string') {
        name = camelize(val);
        res[name] = { type: null };
      } else if (process.env.NODE_ENV !== 'production') {
        warn$2('props must be strings when using array syntax.');
      }
    }
  } else if (isPlainObject(props)) {
    for (var key in props) {
      val = props[key];
      name = camelize(key);
      res[name] = isPlainObject(val)
        ? val
        : { type: val };
    }
  }
  options.props = res;
}

/**
 * Normalize raw function directives into object format.
 */
function normalizeDirectives (options) {
  var dirs = options.directives;
  if (dirs) {
    for (var key in dirs) {
      var def = dirs[key];
      if (typeof def === 'function') {
        dirs[key] = { bind: def, update: def };
      }
    }
  }
}

/**
 * Merge two option objects into a new one.
 * Core utility used in both instantiation and inheritance.
 */
function mergeOptions (
  parent,
  child,
  vm
) {
  if (process.env.NODE_ENV !== 'production') {
    checkComponents(child);
  }
  normalizeProps(child);
  normalizeDirectives(child);
  var extendsFrom = child.extends;
  if (extendsFrom) {
    parent = typeof extendsFrom === 'function'
      ? mergeOptions(parent, extendsFrom.options, vm)
      : mergeOptions(parent, extendsFrom, vm);
  }
  if (child.mixins) {
    for (var i = 0, l = child.mixins.length; i < l; i++) {
      var mixin = child.mixins[i];
      if (mixin.prototype instanceof Vue) {
        mixin = mixin.options;
      }
      parent = mergeOptions(parent, mixin, vm);
    }
  }
  var options = {};
  var key;
  for (key in parent) {
    mergeField(key);
  }
  for (key in child) {
    if (!hasOwn(parent, key)) {
      mergeField(key);
    }
  }
  function mergeField (key) {
    var strat = strats[key] || defaultStrat;
    options[key] = strat(parent[key], child[key], vm, key);
  }
  return options
}

/**
 * Resolve an asset.
 * This function is used because child instances need access
 * to assets defined in its ancestor chain.
 */
function resolveAsset (
  options,
  type,
  id,
  warnMissing
) {
  /* istanbul ignore if */
  if (typeof id !== 'string') {
    return
  }
  var assets = options[type];
  // check local registration variations first
  if (hasOwn(assets, id)) { return assets[id] }
  var camelizedId = camelize(id);
  if (hasOwn(assets, camelizedId)) { return assets[camelizedId] }
  var PascalCaseId = capitalize(camelizedId);
  if (hasOwn(assets, PascalCaseId)) { return assets[PascalCaseId] }
  // fallback to prototype chain
  var res = assets[id] || assets[camelizedId] || assets[PascalCaseId];
  if (process.env.NODE_ENV !== 'production' && warnMissing && !res) {
    warn$2(
      'Failed to resolve ' + type.slice(0, -1) + ': ' + id,
      options
    );
  }
  return res
}

/*  */

function validateProp (
  key,
  propOptions,
  propsData,
  vm
) {
  var prop = propOptions[key];
  var absent = !hasOwn(propsData, key);
  var value = propsData[key];
  // handle boolean props
  if (isType(Boolean, prop.type)) {
    if (absent && !hasOwn(prop, 'default')) {
      value = false;
    } else if (!isType(String, prop.type) && (value === '' || value === hyphenate(key))) {
      value = true;
    }
  }
  // check default value
  if (value === undefined) {
    value = getPropDefaultValue(vm, prop, key);
    // since the default value is a fresh copy,
    // make sure to observe it.
    var prevShouldConvert = observerState.shouldConvert;
    observerState.shouldConvert = true;
    observe(value);
    observerState.shouldConvert = prevShouldConvert;
  }
  if (process.env.NODE_ENV !== 'production') {
    assertProp(prop, key, value, vm, absent);
  }
  return value
}

/**
 * Get the default value of a prop.
 */
function getPropDefaultValue (vm, prop, key) {
  // no default, return undefined
  if (!hasOwn(prop, 'default')) {
    return undefined
  }
  var def = prop.default;
  // warn against non-factory defaults for Object & Array
  if (process.env.NODE_ENV !== 'production' && isObject(def)) {
    warn$2(
      'Invalid default value for prop "' + key + '": ' +
      'Props with type Object/Array must use a factory function ' +
      'to return the default value.',
      vm
    );
  }
  // the raw prop value was also undefined from previous render,
  // return previous default value to avoid unnecessary watcher trigger
  if (vm && vm.$options.propsData &&
    vm.$options.propsData[key] === undefined &&
    vm._props[key] !== undefined) {
    return vm._props[key]
  }
  // call factory function for non-Function types
  // a value is Function if its prototype is function even across different execution context
  return typeof def === 'function' && getType(prop.type) !== 'Function'
    ? def.call(vm)
    : def
}

/**
 * Assert whether a prop is valid.
 */
function assertProp (
  prop,
  name,
  value,
  vm,
  absent
) {
  if (prop.required && absent) {
    warn$2(
      'Missing required prop: "' + name + '"',
      vm
    );
    return
  }
  if (value == null && !prop.required) {
    return
  }
  var type = prop.type;
  var valid = !type || type === true;
  var expectedTypes = [];
  if (type) {
    if (!Array.isArray(type)) {
      type = [type];
    }
    for (var i = 0; i < type.length && !valid; i++) {
      var assertedType = assertType(value, type[i]);
      expectedTypes.push(assertedType.expectedType || '');
      valid = assertedType.valid;
    }
  }
  if (!valid) {
    warn$2(
      'Invalid prop: type check failed for prop "' + name + '".' +
      ' Expected ' + expectedTypes.map(capitalize).join(', ') +
      ', got ' + Object.prototype.toString.call(value).slice(8, -1) + '.',
      vm
    );
    return
  }
  var validator = prop.validator;
  if (validator) {
    if (!validator(value)) {
      warn$2(
        'Invalid prop: custom validator check failed for prop "' + name + '".',
        vm
      );
    }
  }
}

/**
 * Assert the type of a value
 */
function assertType (value, type) {
  var valid;
  var expectedType = getType(type);
  if (expectedType === 'String') {
    valid = typeof value === (expectedType = 'string');
  } else if (expectedType === 'Number') {
    valid = typeof value === (expectedType = 'number');
  } else if (expectedType === 'Boolean') {
    valid = typeof value === (expectedType = 'boolean');
  } else if (expectedType === 'Function') {
    valid = typeof value === (expectedType = 'function');
  } else if (expectedType === 'Object') {
    valid = isPlainObject(value);
  } else if (expectedType === 'Array') {
    valid = Array.isArray(value);
  } else {
    valid = value instanceof type;
  }
  return {
    valid: valid,
    expectedType: expectedType
  }
}

/**
 * Use function string name to check built-in types,
 * because a simple equality check will fail when running
 * across different vms / iframes.
 */
function getType (fn) {
  var match = fn && fn.toString().match(/^\s*function (\w+)/);
  return match && match[1]
}

function isType (type, fn) {
  if (!Array.isArray(fn)) {
    return getType(fn) === getType(type)
  }
  for (var i = 0, len = fn.length; i < len; i++) {
    if (getType(fn[i]) === getType(type)) {
      return true
    }
  }
  /* istanbul ignore next */
  return false
}

function handleError (err, vm, info) {
  if (config.errorHandler) {
    config.errorHandler.call(null, err, vm, info);
  } else {
    if (process.env.NODE_ENV !== 'production') {
      warn$2(("Error in " + info + ":"), vm);
    }
    /* istanbul ignore else */
    if (inBrowser && typeof console !== 'undefined') {
      console.error(err);
    } else {
      throw err
    }
  }
}

/*  */

// attributes that should be using props for binding
var acceptValue = makeMap('input,textarea,option,select');
var mustUseProp = function (tag, type, attr) {
  return (
    (attr === 'value' && acceptValue(tag)) && type !== 'button' ||
    (attr === 'selected' && tag === 'option') ||
    (attr === 'checked' && tag === 'input') ||
    (attr === 'muted' && tag === 'video')
  )
};

var isEnumeratedAttr = makeMap('contenteditable,draggable,spellcheck');

var isBooleanAttr = makeMap(
  'allowfullscreen,async,autofocus,autoplay,checked,compact,controls,declare,' +
  'default,defaultchecked,defaultmuted,defaultselected,defer,disabled,' +
  'enabled,formnovalidate,hidden,indeterminate,inert,ismap,itemscope,loop,multiple,' +
  'muted,nohref,noresize,noshade,novalidate,nowrap,open,pauseonexit,readonly,' +
  'required,reversed,scoped,seamless,selected,sortable,translate,' +
  'truespeed,typemustmatch,visible'
);

/*  */

/*  */



var isHTMLTag = makeMap(
  'html,body,base,head,link,meta,style,title,' +
  'address,article,aside,footer,header,h1,h2,h3,h4,h5,h6,hgroup,nav,section,' +
  'div,dd,dl,dt,figcaption,figure,hr,img,li,main,ol,p,pre,ul,' +
  'a,b,abbr,bdi,bdo,br,cite,code,data,dfn,em,i,kbd,mark,q,rp,rt,rtc,ruby,' +
  's,samp,small,span,strong,sub,sup,time,u,var,wbr,area,audio,map,track,video,' +
  'embed,object,param,source,canvas,script,noscript,del,ins,' +
  'caption,col,colgroup,table,thead,tbody,td,th,tr,' +
  'button,datalist,fieldset,form,input,label,legend,meter,optgroup,option,' +
  'output,progress,select,textarea,' +
  'details,dialog,menu,menuitem,summary,' +
  'content,element,shadow,template'
);

// this map is intentionally selective, only covering SVG elements that may
// contain child elements.
var isSVG = makeMap(
  'svg,animate,circle,clippath,cursor,defs,desc,ellipse,filter,font-face,' +
  'foreignObject,g,glyph,image,line,marker,mask,missing-glyph,path,pattern,' +
  'polygon,polyline,rect,switch,symbol,text,textpath,tspan,use,view',
  true
);

var isPreTag = function (tag) { return tag === 'pre'; };

var isReservedTag = function (tag) {
  return isHTMLTag(tag) || isSVG(tag)
};

function getTagNamespace (tag) {
  if (isSVG(tag)) {
    return 'svg'
  }
  // basic support for MathML
  // note it doesn't support other MathML elements being component roots
  if (tag === 'math') {
    return 'math'
  }
}

/*  */

/**
 * Query an element selector if it's not an element already.
 */

/*  */

var baseOptions = {
  expectHTML: true,
  modules: modules,
  directives: directives,
  isPreTag: isPreTag,
  isUnaryTag: isUnaryTag,
  mustUseProp: mustUseProp,
  canBeLeftOpenTag: canBeLeftOpenTag,
  isReservedTag: isReservedTag,
  getTagNamespace: getTagNamespace,
  staticKeys: genStaticKeys(modules)
};

var ref = createCompiler(baseOptions);
var compile = ref.compile;
var compileToFunctions = ref.compileToFunctions;

/*  */

exports.parseComponent = parseComponent;
exports.compile = compile;
exports.compileToFunctions = compileToFunctions;