daoshiyuyue-teacher/node_modules/vue-i18n/dist/vue-i18n.common.js

/*!
 * vue-i18n v8.20.0 
 * (c) 2020 kazuya kawaguchi
 * Released under the MIT License.
 */
'use strict';

/*  */

/**
 * constants
 */

var numberFormatKeys = [
  'style',
  'currency',
  'currencyDisplay',
  'useGrouping',
  'minimumIntegerDigits',
  'minimumFractionDigits',
  'maximumFractionDigits',
  'minimumSignificantDigits',
  'maximumSignificantDigits',
  'localeMatcher',
  'formatMatcher',
  'unit'
];

/**
 * utilities
 */

function warn (msg, err) {
  if (typeof console !== 'undefined') {
    console.warn('[vue-i18n] ' + msg);
    /* istanbul ignore if */
    if (err) {
      console.warn(err.stack);
    }
  }
}

function error (msg, err) {
  if (typeof console !== 'undefined') {
    console.error('[vue-i18n] ' + msg);
    /* istanbul ignore if */
    if (err) {
      console.error(err.stack);
    }
  }
}

var isArray = Array.isArray;

function isObject (obj) {
  return obj !== null && typeof obj === 'object'
}

function isBoolean (val) {
  return typeof val === 'boolean'
}

function isString (val) {
  return typeof val === 'string'
}

var toString = Object.prototype.toString;
var OBJECT_STRING = '[object Object]';
function isPlainObject (obj) {
  return toString.call(obj) === OBJECT_STRING
}

function isNull (val) {
  return val === null || val === undefined
}

function parseArgs () {
  var args = [], len = arguments.length;
  while ( len-- ) args[ len ] = arguments[ len ];

  var locale = null;
  var params = null;
  if (args.length === 1) {
    if (isObject(args[0]) || Array.isArray(args[0])) {
      params = args[0];
    } else if (typeof args[0] === 'string') {
      locale = args[0];
    }
  } else if (args.length === 2) {
    if (typeof args[0] === 'string') {
      locale = args[0];
    }
    /* istanbul ignore if */
    if (isObject(args[1]) || Array.isArray(args[1])) {
      params = args[1];
    }
  }

  return { locale: locale, params: params }
}

function looseClone (obj) {
  return JSON.parse(JSON.stringify(obj))
}

function remove (arr, item) {
  if (arr.length) {
    var index = arr.indexOf(item);
    if (index > -1) {
      return arr.splice(index, 1)
    }
  }
}

function includes (arr, item) {
  return !!~arr.indexOf(item)
}

var hasOwnProperty = Object.prototype.hasOwnProperty;
function hasOwn (obj, key) {
  return hasOwnProperty.call(obj, key)
}

function merge (target) {
  var arguments$1 = arguments;

  var output = Object(target);
  for (var i = 1; i < arguments.length; i++) {
    var source = arguments$1[i];
    if (source !== undefined && source !== null) {
      var key = (void 0);
      for (key in source) {
        if (hasOwn(source, key)) {
          if (isObject(source[key])) {
            output[key] = merge(output[key], source[key]);
          } else {
            output[key] = source[key];
          }
        }
      }
    }
  }
  return output
}

function looseEqual (a, b) {
  if (a === b) { return true }
  var isObjectA = isObject(a);
  var isObjectB = isObject(b);
  if (isObjectA && isObjectB) {
    try {
      var isArrayA = Array.isArray(a);
      var isArrayB = Array.isArray(b);
      if (isArrayA && isArrayB) {
        return a.length === b.length && a.every(function (e, i) {
          return looseEqual(e, b[i])
        })
      } else if (!isArrayA && !isArrayB) {
        var keysA = Object.keys(a);
        var keysB = Object.keys(b);
        return keysA.length === keysB.length && keysA.every(function (key) {
          return looseEqual(a[key], b[key])
        })
      } else {
        /* istanbul ignore next */
        return false
      }
    } catch (e) {
      /* istanbul ignore next */
      return false
    }
  } else if (!isObjectA && !isObjectB) {
    return String(a) === String(b)
  } else {
    return false
  }
}

/*  */

function extend (Vue) {
  if (!Vue.prototype.hasOwnProperty('$i18n')) {
    // $FlowFixMe
    Object.defineProperty(Vue.prototype, '$i18n', {
      get: function get () { return this._i18n }
    });
  }

  Vue.prototype.$t = function (key) {
    var values = [], len = arguments.length - 1;
    while ( len-- > 0 ) values[ len ] = arguments[ len + 1 ];

    var i18n = this.$i18n;
    return i18n._t.apply(i18n, [ key, i18n.locale, i18n._getMessages(), this ].concat( values ))
  };

  Vue.prototype.$tc = function (key, choice) {
    var values = [], len = arguments.length - 2;
    while ( len-- > 0 ) values[ len ] = arguments[ len + 2 ];

    var i18n = this.$i18n;
    return i18n._tc.apply(i18n, [ key, i18n.locale, i18n._getMessages(), this, choice ].concat( values ))
  };

  Vue.prototype.$te = function (key, locale) {
    var i18n = this.$i18n;
    return i18n._te(key, i18n.locale, i18n._getMessages(), locale)
  };

  Vue.prototype.$d = function (value) {
    var ref;

    var args = [], len = arguments.length - 1;
    while ( len-- > 0 ) args[ len ] = arguments[ len + 1 ];
    return (ref = this.$i18n).d.apply(ref, [ value ].concat( args ))
  };

  Vue.prototype.$n = function (value) {
    var ref;

    var args = [], len = arguments.length - 1;
    while ( len-- > 0 ) args[ len ] = arguments[ len + 1 ];
    return (ref = this.$i18n).n.apply(ref, [ value ].concat( args ))
  };
}

/*  */

var mixin = {
  beforeCreate: function beforeCreate () {
    var options = this.$options;
    options.i18n = options.i18n || (options.__i18n ? {} : null);

    if (options.i18n) {
      if (options.i18n instanceof VueI18n) {
        // init locale messages via custom blocks
        if (options.__i18n) {
          try {
            var localeMessages = {};
            options.__i18n.forEach(function (resource) {
              localeMessages = merge(localeMessages, JSON.parse(resource));
            });
            Object.keys(localeMessages).forEach(function (locale) {
              options.i18n.mergeLocaleMessage(locale, localeMessages[locale]);
            });
          } catch (e) {
            if (process.env.NODE_ENV !== 'production') {
              error("Cannot parse locale messages via custom blocks.", e);
            }
          }
        }
        this._i18n = options.i18n;
        this._i18nWatcher = this._i18n.watchI18nData();
      } else if (isPlainObject(options.i18n)) {
        var rootI18n = this.$root && this.$root.$i18n && this.$root.$i18n instanceof VueI18n
          ? this.$root.$i18n
          : null;
        // component local i18n
        if (rootI18n) {
          options.i18n.root = this.$root;
          options.i18n.formatter = rootI18n.formatter;
          options.i18n.fallbackLocale = rootI18n.fallbackLocale;
          options.i18n.formatFallbackMessages = rootI18n.formatFallbackMessages;
          options.i18n.silentTranslationWarn = rootI18n.silentTranslationWarn;
          options.i18n.silentFallbackWarn = rootI18n.silentFallbackWarn;
          options.i18n.pluralizationRules = rootI18n.pluralizationRules;
          options.i18n.preserveDirectiveContent = rootI18n.preserveDirectiveContent;
        }

        // init locale messages via custom blocks
        if (options.__i18n) {
          try {
            var localeMessages$1 = {};
            options.__i18n.forEach(function (resource) {
              localeMessages$1 = merge(localeMessages$1, JSON.parse(resource));
            });
            options.i18n.messages = localeMessages$1;
          } catch (e) {
            if (process.env.NODE_ENV !== 'production') {
              warn("Cannot parse locale messages via custom blocks.", e);
            }
          }
        }

        var ref = options.i18n;
        var sharedMessages = ref.sharedMessages;
        if (sharedMessages && isPlainObject(sharedMessages)) {
          options.i18n.messages = merge(options.i18n.messages, sharedMessages);
        }

        this._i18n = new VueI18n(options.i18n);
        this._i18nWatcher = this._i18n.watchI18nData();

        if (options.i18n.sync === undefined || !!options.i18n.sync) {
          this._localeWatcher = this.$i18n.watchLocale();
        }

        if (rootI18n) {
          rootI18n.onComponentInstanceCreated(this._i18n);
        }
      } else {
        if (process.env.NODE_ENV !== 'production') {
          warn("Cannot be interpreted 'i18n' option.");
        }
      }
    } else if (this.$root && this.$root.$i18n && this.$root.$i18n instanceof VueI18n) {
      // root i18n
      this._i18n = this.$root.$i18n;
    } else if (options.parent && options.parent.$i18n && options.parent.$i18n instanceof VueI18n) {
      // parent i18n
      this._i18n = options.parent.$i18n;
    }
  },

  beforeMount: function beforeMount () {
    var options = this.$options;
    options.i18n = options.i18n || (options.__i18n ? {} : null);

    if (options.i18n) {
      if (options.i18n instanceof VueI18n) {
        // init locale messages via custom blocks
        this._i18n.subscribeDataChanging(this);
        this._subscribing = true;
      } else if (isPlainObject(options.i18n)) {
        this._i18n.subscribeDataChanging(this);
        this._subscribing = true;
      } else {
        if (process.env.NODE_ENV !== 'production') {
          warn("Cannot be interpreted 'i18n' option.");
        }
      }
    } else if (this.$root && this.$root.$i18n && this.$root.$i18n instanceof VueI18n) {
      this._i18n.subscribeDataChanging(this);
      this._subscribing = true;
    } else if (options.parent && options.parent.$i18n && options.parent.$i18n instanceof VueI18n) {
      this._i18n.subscribeDataChanging(this);
      this._subscribing = true;
    }
  },

  beforeDestroy: function beforeDestroy () {
    if (!this._i18n) { return }

    var self = this;
    this.$nextTick(function () {
      if (self._subscribing) {
        self._i18n.unsubscribeDataChanging(self);
        delete self._subscribing;
      }

      if (self._i18nWatcher) {
        self._i18nWatcher();
        self._i18n.destroyVM();
        delete self._i18nWatcher;
      }

      if (self._localeWatcher) {
        self._localeWatcher();
        delete self._localeWatcher;
      }
    });
  }
};

/*  */

var interpolationComponent = {
  name: 'i18n',
  functional: true,
  props: {
    tag: {
      type: [String, Boolean, Object],
      default: 'span'
    },
    path: {
      type: String,
      required: true
    },
    locale: {
      type: String
    },
    places: {
      type: [Array, Object]
    }
  },
  render: function render (h, ref) {
    var data = ref.data;
    var parent = ref.parent;
    var props = ref.props;
    var slots = ref.slots;

    var $i18n = parent.$i18n;
    if (!$i18n) {
      if (process.env.NODE_ENV !== 'production') {
        warn('Cannot find VueI18n instance!');
      }
      return
    }

    var path = props.path;
    var locale = props.locale;
    var places = props.places;
    var params = slots();
    var children = $i18n.i(
      path,
      locale,
      onlyHasDefaultPlace(params) || places
        ? useLegacyPlaces(params.default, places)
        : params
    );

    var tag = (!!props.tag && props.tag !== true) || props.tag === false ? props.tag : 'span';
    return tag ? h(tag, data, children) : children
  }
};

function onlyHasDefaultPlace (params) {
  var prop;
  for (prop in params) {
    if (prop !== 'default') { return false }
  }
  return Boolean(prop)
}

function useLegacyPlaces (children, places) {
  var params = places ? createParamsFromPlaces(places) : {};

  if (!children) { return params }

  // Filter empty text nodes
  children = children.filter(function (child) {
    return child.tag || child.text.trim() !== ''
  });

  var everyPlace = children.every(vnodeHasPlaceAttribute);
  if (process.env.NODE_ENV !== 'production' && everyPlace) {
    warn('`place` attribute is deprecated in next major version. Please switch to Vue slots.');
  }

  return children.reduce(
    everyPlace ? assignChildPlace : assignChildIndex,
    params
  )
}

function createParamsFromPlaces (places) {
  if (process.env.NODE_ENV !== 'production') {
    warn('`places` prop is deprecated in next major version. Please switch to Vue slots.');
  }

  return Array.isArray(places)
    ? places.reduce(assignChildIndex, {})
    : Object.assign({}, places)
}

function assignChildPlace (params, child) {
  if (child.data && child.data.attrs && child.data.attrs.place) {
    params[child.data.attrs.place] = child;
  }
  return params
}

function assignChildIndex (params, child, index) {
  params[index] = child;
  return params
}

function vnodeHasPlaceAttribute (vnode) {
  return Boolean(vnode.data && vnode.data.attrs && vnode.data.attrs.place)
}

/*  */

var numberComponent = {
  name: 'i18n-n',
  functional: true,
  props: {
    tag: {
      type: [String, Boolean, Object],
      default: 'span'
    },
    value: {
      type: Number,
      required: true
    },
    format: {
      type: [String, Object]
    },
    locale: {
      type: String
    }
  },
  render: function render (h, ref) {
    var props = ref.props;
    var parent = ref.parent;
    var data = ref.data;

    var i18n = parent.$i18n;

    if (!i18n) {
      if (process.env.NODE_ENV !== 'production') {
        warn('Cannot find VueI18n instance!');
      }
      return null
    }

    var key = null;
    var options = null;

    if (isString(props.format)) {
      key = props.format;
    } else if (isObject(props.format)) {
      if (props.format.key) {
        key = props.format.key;
      }

      // Filter out number format options only
      options = Object.keys(props.format).reduce(function (acc, prop) {
        var obj;

        if (includes(numberFormatKeys, prop)) {
          return Object.assign({}, acc, ( obj = {}, obj[prop] = props.format[prop], obj ))
        }
        return acc
      }, null);
    }

    var locale = props.locale || i18n.locale;
    var parts = i18n._ntp(props.value, locale, key, options);

    var values = parts.map(function (part, index) {
      var obj;

      var slot = data.scopedSlots && data.scopedSlots[part.type];
      return slot ? slot(( obj = {}, obj[part.type] = part.value, obj.index = index, obj.parts = parts, obj )) : part.value
    });

    var tag = (!!props.tag && props.tag !== true) || props.tag === false ? props.tag : 'span';
    return tag
      ? h(tag, {
        attrs: data.attrs,
        'class': data['class'],
        staticClass: data.staticClass
      }, values)
      : values
  }
};

/*  */

function bind (el, binding, vnode) {
  if (!assert(el, vnode)) { return }

  t(el, binding, vnode);
}

function update (el, binding, vnode, oldVNode) {
  if (!assert(el, vnode)) { return }

  var i18n = vnode.context.$i18n;
  if (localeEqual(el, vnode) &&
    (looseEqual(binding.value, binding.oldValue) &&
     looseEqual(el._localeMessage, i18n.getLocaleMessage(i18n.locale)))) { return }

  t(el, binding, vnode);
}

function unbind (el, binding, vnode, oldVNode) {
  var vm = vnode.context;
  if (!vm) {
    warn('Vue instance does not exists in VNode context');
    return
  }

  var i18n = vnode.context.$i18n || {};
  if (!binding.modifiers.preserve && !i18n.preserveDirectiveContent) {
    el.textContent = '';
  }
  el._vt = undefined;
  delete el['_vt'];
  el._locale = undefined;
  delete el['_locale'];
  el._localeMessage = undefined;
  delete el['_localeMessage'];
}

function assert (el, vnode) {
  var vm = vnode.context;
  if (!vm) {
    warn('Vue instance does not exists in VNode context');
    return false
  }

  if (!vm.$i18n) {
    warn('VueI18n instance does not exists in Vue instance');
    return false
  }

  return true
}

function localeEqual (el, vnode) {
  var vm = vnode.context;
  return el._locale === vm.$i18n.locale
}

function t (el, binding, vnode) {
  var ref$1, ref$2;

  var value = binding.value;

  var ref = parseValue(value);
  var path = ref.path;
  var locale = ref.locale;
  var args = ref.args;
  var choice = ref.choice;
  if (!path && !locale && !args) {
    warn('value type not supported');
    return
  }

  if (!path) {
    warn('`path` is required in v-t directive');
    return
  }

  var vm = vnode.context;
  if (choice != null) {
    el._vt = el.textContent = (ref$1 = vm.$i18n).tc.apply(ref$1, [ path, choice ].concat( makeParams(locale, args) ));
  } else {
    el._vt = el.textContent = (ref$2 = vm.$i18n).t.apply(ref$2, [ path ].concat( makeParams(locale, args) ));
  }
  el._locale = vm.$i18n.locale;
  el._localeMessage = vm.$i18n.getLocaleMessage(vm.$i18n.locale);
}

function parseValue (value) {
  var path;
  var locale;
  var args;
  var choice;

  if (isString(value)) {
    path = value;
  } else if (isPlainObject(value)) {
    path = value.path;
    locale = value.locale;
    args = value.args;
    choice = value.choice;
  }

  return { path: path, locale: locale, args: args, choice: choice }
}

function makeParams (locale, args) {
  var params = [];

  locale && params.push(locale);
  if (args && (Array.isArray(args) || isPlainObject(args))) {
    params.push(args);
  }

  return params
}

var Vue;

function install (_Vue) {
  /* istanbul ignore if */
  if (process.env.NODE_ENV !== 'production' && install.installed && _Vue === Vue) {
    warn('already installed.');
    return
  }
  install.installed = true;

  Vue = _Vue;

  var version = (Vue.version && Number(Vue.version.split('.')[0])) || -1;
  /* istanbul ignore if */
  if (process.env.NODE_ENV !== 'production' && version < 2) {
    warn(("vue-i18n (" + (install.version) + ") need to use Vue 2.0 or later (Vue: " + (Vue.version) + ")."));
    return
  }

  extend(Vue);
  Vue.mixin(mixin);
  Vue.directive('t', { bind: bind, update: update, unbind: unbind });
  Vue.component(interpolationComponent.name, interpolationComponent);
  Vue.component(numberComponent.name, numberComponent);

  // use simple mergeStrategies to prevent i18n instance lose '__proto__'
  var strats = Vue.config.optionMergeStrategies;
  strats.i18n = function (parentVal, childVal) {
    return childVal === undefined
      ? parentVal
      : childVal
  };
}

/*  */

var BaseFormatter = function BaseFormatter () {
  this._caches = Object.create(null);
};

BaseFormatter.prototype.interpolate = function interpolate (message, values) {
  if (!values) {
    return [message]
  }
  var tokens = this._caches[message];
  if (!tokens) {
    tokens = parse(message);
    this._caches[message] = tokens;
  }
  return compile(tokens, values)
};



var RE_TOKEN_LIST_VALUE = /^(?:\d)+/;
var RE_TOKEN_NAMED_VALUE = /^(?:\w)+/;

function parse (format) {
  var tokens = [];
  var position = 0;

  var text = '';
  while (position < format.length) {
    var char = format[position++];
    if (char === '{') {
      if (text) {
        tokens.push({ type: 'text', value: text });
      }

      text = '';
      var sub = '';
      char = format[position++];
      while (char !== undefined && char !== '}') {
        sub += char;
        char = format[position++];
      }
      var isClosed = char === '}';

      var type = RE_TOKEN_LIST_VALUE.test(sub)
        ? 'list'
        : isClosed && RE_TOKEN_NAMED_VALUE.test(sub)
          ? 'named'
          : 'unknown';
      tokens.push({ value: sub, type: type });
    } else if (char === '%') {
      // when found rails i18n syntax, skip text capture
      if (format[(position)] !== '{') {
        text += char;
      }
    } else {
      text += char;
    }
  }

  text && tokens.push({ type: 'text', value: text });

  return tokens
}

function compile (tokens, values) {
  var compiled = [];
  var index = 0;

  var mode = Array.isArray(values)
    ? 'list'
    : isObject(values)
      ? 'named'
      : 'unknown';
  if (mode === 'unknown') { return compiled }

  while (index < tokens.length) {
    var token = tokens[index];
    switch (token.type) {
      case 'text':
        compiled.push(token.value);
        break
      case 'list':
        compiled.push(values[parseInt(token.value, 10)]);
        break
      case 'named':
        if (mode === 'named') {
          compiled.push((values)[token.value]);
        } else {
          if (process.env.NODE_ENV !== 'production') {
            warn(("Type of token '" + (token.type) + "' and format of value '" + mode + "' don't match!"));
          }
        }
        break
      case 'unknown':
        if (process.env.NODE_ENV !== 'production') {
          warn("Detect 'unknown' type of token!");
        }
        break
    }
    index++;
  }

  return compiled
}

/*  */

/**
 *  Path parser
 *  - Inspired:
 *    Vue.js Path parser
 */

// actions
var APPEND = 0;
var PUSH = 1;
var INC_SUB_PATH_DEPTH = 2;
var PUSH_SUB_PATH = 3;

// states
var BEFORE_PATH = 0;
var IN_PATH = 1;
var BEFORE_IDENT = 2;
var IN_IDENT = 3;
var IN_SUB_PATH = 4;
var IN_SINGLE_QUOTE = 5;
var IN_DOUBLE_QUOTE = 6;
var AFTER_PATH = 7;
var ERROR = 8;

var pathStateMachine = [];

pathStateMachine[BEFORE_PATH] = {
  'ws': [BEFORE_PATH],
  'ident': [IN_IDENT, APPEND],
  '[': [IN_SUB_PATH],
  'eof': [AFTER_PATH]
};

pathStateMachine[IN_PATH] = {
  'ws': [IN_PATH],
  '.': [BEFORE_IDENT],
  '[': [IN_SUB_PATH],
  'eof': [AFTER_PATH]
};

pathStateMachine[BEFORE_IDENT] = {
  'ws': [BEFORE_IDENT],
  'ident': [IN_IDENT, APPEND],
  '0': [IN_IDENT, APPEND],
  'number': [IN_IDENT, APPEND]
};

pathStateMachine[IN_IDENT] = {
  'ident': [IN_IDENT, APPEND],
  '0': [IN_IDENT, APPEND],
  'number': [IN_IDENT, APPEND],
  'ws': [IN_PATH, PUSH],
  '.': [BEFORE_IDENT, PUSH],
  '[': [IN_SUB_PATH, PUSH],
  'eof': [AFTER_PATH, PUSH]
};

pathStateMachine[IN_SUB_PATH] = {
  "'": [IN_SINGLE_QUOTE, APPEND],
  '"': [IN_DOUBLE_QUOTE, APPEND],
  '[': [IN_SUB_PATH, INC_SUB_PATH_DEPTH],
  ']': [IN_PATH, PUSH_SUB_PATH],
  'eof': ERROR,
  'else': [IN_SUB_PATH, APPEND]
};

pathStateMachine[IN_SINGLE_QUOTE] = {
  "'": [IN_SUB_PATH, APPEND],
  'eof': ERROR,
  'else': [IN_SINGLE_QUOTE, APPEND]
};

pathStateMachine[IN_DOUBLE_QUOTE] = {
  '"': [IN_SUB_PATH, APPEND],
  'eof': ERROR,
  'else': [IN_DOUBLE_QUOTE, APPEND]
};

/**
 * Check if an expression is a literal value.
 */

var literalValueRE = /^\s?(?:true|false|-?[\d.]+|'[^']*'|"[^"]*")\s?$/;
function isLiteral (exp) {
  return literalValueRE.test(exp)
}

/**
 * Strip quotes from a string
 */

function stripQuotes (str) {
  var a = str.charCodeAt(0);
  var b = str.charCodeAt(str.length - 1);
  return a === b && (a === 0x22 || a === 0x27)
    ? str.slice(1, -1)
    : str
}

/**
 * Determine the type of a character in a keypath.
 */

function getPathCharType (ch) {
  if (ch === undefined || ch === null) { return 'eof' }

  var code = ch.charCodeAt(0);

  switch (code) {
    case 0x5B: // [
    case 0x5D: // ]
    case 0x2E: // .
    case 0x22: // "
    case 0x27: // '
      return ch

    case 0x5F: // _
    case 0x24: // $
    case 0x2D: // -
      return 'ident'

    case 0x09: // Tab
    case 0x0A: // Newline
    case 0x0D: // Return
    case 0xA0:  // No-break space
    case 0xFEFF:  // Byte Order Mark
    case 0x2028:  // Line Separator
    case 0x2029:  // Paragraph Separator
      return 'ws'
  }

  return 'ident'
}

/**
 * Format a subPath, return its plain form if it is
 * a literal string or number. Otherwise prepend the
 * dynamic indicator (*).
 */

function formatSubPath (path) {
  var trimmed = path.trim();
  // invalid leading 0
  if (path.charAt(0) === '0' && isNaN(path)) { return false }

  return isLiteral(trimmed) ? stripQuotes(trimmed) : '*' + trimmed
}

/**
 * Parse a string path into an array of segments
 */

function parse$1 (path) {
  var keys = [];
  var index = -1;
  var mode = BEFORE_PATH;
  var subPathDepth = 0;
  var c;
  var key;
  var newChar;
  var type;
  var transition;
  var action;
  var typeMap;
  var actions = [];

  actions[PUSH] = function () {
    if (key !== undefined) {
      keys.push(key);
      key = undefined;
    }
  };

  actions[APPEND] = function () {
    if (key === undefined) {
      key = newChar;
    } else {
      key += newChar;
    }
  };

  actions[INC_SUB_PATH_DEPTH] = function () {
    actions[APPEND]();
    subPathDepth++;
  };

  actions[PUSH_SUB_PATH] = function () {
    if (subPathDepth > 0) {
      subPathDepth--;
      mode = IN_SUB_PATH;
      actions[APPEND]();
    } else {
      subPathDepth = 0;
      if (key === undefined) { return false }
      key = formatSubPath(key);
      if (key === false) {
        return false
      } else {
        actions[PUSH]();
      }
    }
  };

  function maybeUnescapeQuote () {
    var nextChar = path[index + 1];
    if ((mode === IN_SINGLE_QUOTE && nextChar === "'") ||
      (mode === IN_DOUBLE_QUOTE && nextChar === '"')) {
      index++;
      newChar = '\\' + nextChar;
      actions[APPEND]();
      return true
    }
  }

  while (mode !== null) {
    index++;
    c = path[index];

    if (c === '\\' && maybeUnescapeQuote()) {
      continue
    }

    type = getPathCharType(c);
    typeMap = pathStateMachine[mode];
    transition = typeMap[type] || typeMap['else'] || ERROR;

    if (transition === ERROR) {
      return // parse error
    }

    mode = transition[0];
    action = actions[transition[1]];
    if (action) {
      newChar = transition[2];
      newChar = newChar === undefined
        ? c
        : newChar;
      if (action() === false) {
        return
      }
    }

    if (mode === AFTER_PATH) {
      return keys
    }
  }
}





var I18nPath = function I18nPath () {
  this._cache = Object.create(null);
};

/**
 * External parse that check for a cache hit first
 */
I18nPath.prototype.parsePath = function parsePath (path) {
  var hit = this._cache[path];
  if (!hit) {
    hit = parse$1(path);
    if (hit) {
      this._cache[path] = hit;
    }
  }
  return hit || []
};

/**
 * Get path value from path string
 */
I18nPath.prototype.getPathValue = function getPathValue (obj, path) {
  if (!isObject(obj)) { return null }

  var paths = this.parsePath(path);
  if (paths.length === 0) {
    return null
  } else {
    var length = paths.length;
    var last = obj;
    var i = 0;
    while (i < length) {
      var value = last[paths[i]];
      if (value === undefined) {
        return null
      }
      last = value;
      i++;
    }

    return last
  }
};

/*  */



var htmlTagMatcher = /<\/?[\w\s="/.':;#-\/]+>/;
var linkKeyMatcher = /(?:@(?:\.[a-z]+)?:(?:[\w\-_|.]+|\([\w\-_|.]+\)))/g;
var linkKeyPrefixMatcher = /^@(?:\.([a-z]+))?:/;
var bracketsMatcher = /[()]/g;
var defaultModifiers = {
  'upper': function (str) { return str.toLocaleUpperCase(); },
  'lower': function (str) { return str.toLocaleLowerCase(); },
  'capitalize': function (str) { return ("" + (str.charAt(0).toLocaleUpperCase()) + (str.substr(1))); }
};

var defaultFormatter = new BaseFormatter();

var VueI18n = function VueI18n (options) {
  var this$1 = this;
  if ( options === void 0 ) options = {};

  // Auto install if it is not done yet and `window` has `Vue`.
  // To allow users to avoid auto-installation in some cases,
  // this code should be placed here. See #290
  /* istanbul ignore if */
  if (!Vue && typeof window !== 'undefined' && window.Vue) {
    install(window.Vue);
  }

  var locale = options.locale || 'en-US';
  var fallbackLocale = options.fallbackLocale === false
    ? false
    : options.fallbackLocale || 'en-US';
  var messages = options.messages || {};
  var dateTimeFormats = options.dateTimeFormats || {};
  var numberFormats = options.numberFormats || {};

  this._vm = null;
  this._formatter = options.formatter || defaultFormatter;
  this._modifiers = options.modifiers || {};
  this._missing = options.missing || null;
  this._root = options.root || null;
  this._sync = options.sync === undefined ? true : !!options.sync;
  this._fallbackRoot = options.fallbackRoot === undefined
    ? true
    : !!options.fallbackRoot;
  this._formatFallbackMessages = options.formatFallbackMessages === undefined
    ? false
    : !!options.formatFallbackMessages;
  this._silentTranslationWarn = options.silentTranslationWarn === undefined
    ? false
    : options.silentTranslationWarn;
  this._silentFallbackWarn = options.silentFallbackWarn === undefined
    ? false
    : !!options.silentFallbackWarn;
  this._dateTimeFormatters = {};
  this._numberFormatters = {};
  this._path = new I18nPath();
  this._dataListeners = [];
  this._componentInstanceCreatedListener = options.componentInstanceCreatedListener || null;
  this._preserveDirectiveContent = options.preserveDirectiveContent === undefined
    ? false
    : !!options.preserveDirectiveContent;
  this.pluralizationRules = options.pluralizationRules || {};
  this._warnHtmlInMessage = options.warnHtmlInMessage || 'off';
  this._postTranslation = options.postTranslation || null;

  /**
   * @param choice {number} a choice index given by the input to $tc: `$tc('path.to.rule', choiceIndex)`
   * @param choicesLength {number} an overall amount of available choices
   * @returns a final choice index
  */
  this.getChoiceIndex = function (choice, choicesLength) {
    var thisPrototype = Object.getPrototypeOf(this$1);
    if (thisPrototype && thisPrototype.getChoiceIndex) {
      var prototypeGetChoiceIndex = (thisPrototype.getChoiceIndex);
      return (prototypeGetChoiceIndex).call(this$1, choice, choicesLength)
    }

    // Default (old) getChoiceIndex implementation - english-compatible
    var defaultImpl = function (_choice, _choicesLength) {
      _choice = Math.abs(_choice);

      if (_choicesLength === 2) {
        return _choice
          ? _choice > 1
            ? 1
            : 0
          : 1
      }

      return _choice ? Math.min(_choice, 2) : 0
    };

    if (this$1.locale in this$1.pluralizationRules) {
      return this$1.pluralizationRules[this$1.locale].apply(this$1, [choice, choicesLength])
    } else {
      return defaultImpl(choice, choicesLength)
    }
  };


  this._exist = function (message, key) {
    if (!message || !key) { return false }
    if (!isNull(this$1._path.getPathValue(message, key))) { return true }
    // fallback for flat key
    if (message[key]) { return true }
    return false
  };

  if (this._warnHtmlInMessage === 'warn' || this._warnHtmlInMessage === 'error') {
    Object.keys(messages).forEach(function (locale) {
      this$1._checkLocaleMessage(locale, this$1._warnHtmlInMessage, messages[locale]);
    });
  }

  this._initVM({
    locale: locale,
    fallbackLocale: fallbackLocale,
    messages: messages,
    dateTimeFormats: dateTimeFormats,
    numberFormats: numberFormats
  });
};

var prototypeAccessors = { vm: { configurable: true },messages: { configurable: true },dateTimeFormats: { configurable: true },numberFormats: { configurable: true },availableLocales: { configurable: true },locale: { configurable: true },fallbackLocale: { configurable: true },formatFallbackMessages: { configurable: true },missing: { configurable: true },formatter: { configurable: true },silentTranslationWarn: { configurable: true },silentFallbackWarn: { configurable: true },preserveDirectiveContent: { configurable: true },warnHtmlInMessage: { configurable: true },postTranslation: { configurable: true } };

VueI18n.prototype._checkLocaleMessage = function _checkLocaleMessage (locale, level, message) {
  var paths = [];

  var fn = function (level, locale, message, paths) {
    if (isPlainObject(message)) {
      Object.keys(message).forEach(function (key) {
        var val = message[key];
        if (isPlainObject(val)) {
          paths.push(key);
          paths.push('.');
          fn(level, locale, val, paths);
          paths.pop();
          paths.pop();
        } else {
          paths.push(key);
          fn(level, locale, val, paths);
          paths.pop();
        }
      });
    } else if (Array.isArray(message)) {
      message.forEach(function (item, index) {
        if (isPlainObject(item)) {
          paths.push(("[" + index + "]"));
          paths.push('.');
          fn(level, locale, item, paths);
          paths.pop();
          paths.pop();
        } else {
          paths.push(("[" + index + "]"));
          fn(level, locale, item, paths);
          paths.pop();
        }
      });
    } else if (isString(message)) {
      var ret = htmlTagMatcher.test(message);
      if (ret) {
        var msg = "Detected HTML in message '" + message + "' of keypath '" + (paths.join('')) + "' at '" + locale + "'. Consider component interpolation with '<i18n>' to avoid XSS. See https://bit.ly/2ZqJzkp";
        if (level === 'warn') {
          warn(msg);
        } else if (level === 'error') {
          error(msg);
        }
      }
    }
  };

  fn(level, locale, message, paths);
};

VueI18n.prototype._initVM = function _initVM (data) {
  var silent = Vue.config.silent;
  Vue.config.silent = true;
  this._vm = new Vue({ data: data });
  Vue.config.silent = silent;
};

VueI18n.prototype.destroyVM = function destroyVM () {
  this._vm.$destroy();
};

VueI18n.prototype.subscribeDataChanging = function subscribeDataChanging (vm) {
  this._dataListeners.push(vm);
};

VueI18n.prototype.unsubscribeDataChanging = function unsubscribeDataChanging (vm) {
  remove(this._dataListeners, vm);
};

VueI18n.prototype.watchI18nData = function watchI18nData () {
  var self = this;
  return this._vm.$watch('$data', function () {
    var i = self._dataListeners.length;
    while (i--) {
      Vue.nextTick(function () {
        self._dataListeners[i] && self._dataListeners[i].$forceUpdate();
      });
    }
  }, { deep: true })
};

VueI18n.prototype.watchLocale = function watchLocale () {
  /* istanbul ignore if */
  if (!this._sync || !this._root) { return null }
  var target = this._vm;
  return this._root.$i18n.vm.$watch('locale', function (val) {
    target.$set(target, 'locale', val);
    target.$forceUpdate();
  }, { immediate: true })
};

VueI18n.prototype.onComponentInstanceCreated = function onComponentInstanceCreated (newI18n) {
  if (this._componentInstanceCreatedListener) {
    this._componentInstanceCreatedListener(newI18n, this);
  }
};

prototypeAccessors.vm.get = function () { return this._vm };

prototypeAccessors.messages.get = function () { return looseClone(this._getMessages()) };
prototypeAccessors.dateTimeFormats.get = function () { return looseClone(this._getDateTimeFormats()) };
prototypeAccessors.numberFormats.get = function () { return looseClone(this._getNumberFormats()) };
prototypeAccessors.availableLocales.get = function () { return Object.keys(this.messages).sort() };

prototypeAccessors.locale.get = function () { return this._vm.locale };
prototypeAccessors.locale.set = function (locale) {
  this._vm.$set(this._vm, 'locale', locale);
};

prototypeAccessors.fallbackLocale.get = function () { return this._vm.fallbackLocale };
prototypeAccessors.fallbackLocale.set = function (locale) {
  this._localeChainCache = {};
  this._vm.$set(this._vm, 'fallbackLocale', locale);
};

prototypeAccessors.formatFallbackMessages.get = function () { return this._formatFallbackMessages };
prototypeAccessors.formatFallbackMessages.set = function (fallback) { this._formatFallbackMessages = fallback; };

prototypeAccessors.missing.get = function () { return this._missing };
prototypeAccessors.missing.set = function (handler) { this._missing = handler; };

prototypeAccessors.formatter.get = function () { return this._formatter };
prototypeAccessors.formatter.set = function (formatter) { this._formatter = formatter; };

prototypeAccessors.silentTranslationWarn.get = function () { return this._silentTranslationWarn };
prototypeAccessors.silentTranslationWarn.set = function (silent) { this._silentTranslationWarn = silent; };

prototypeAccessors.silentFallbackWarn.get = function () { return this._silentFallbackWarn };
prototypeAccessors.silentFallbackWarn.set = function (silent) { this._silentFallbackWarn = silent; };

prototypeAccessors.preserveDirectiveContent.get = function () { return this._preserveDirectiveContent };
prototypeAccessors.preserveDirectiveContent.set = function (preserve) { this._preserveDirectiveContent = preserve; };

prototypeAccessors.warnHtmlInMessage.get = function () { return this._warnHtmlInMessage };
prototypeAccessors.warnHtmlInMessage.set = function (level) {
    var this$1 = this;

  var orgLevel = this._warnHtmlInMessage;
  this._warnHtmlInMessage = level;
  if (orgLevel !== level && (level === 'warn' || level === 'error')) {
    var messages = this._getMessages();
    Object.keys(messages).forEach(function (locale) {
      this$1._checkLocaleMessage(locale, this$1._warnHtmlInMessage, messages[locale]);
    });
  }
};

prototypeAccessors.postTranslation.get = function () { return this._postTranslation };
prototypeAccessors.postTranslation.set = function (handler) { this._postTranslation = handler; };

VueI18n.prototype._getMessages = function _getMessages () { return this._vm.messages };
VueI18n.prototype._getDateTimeFormats = function _getDateTimeFormats () { return this._vm.dateTimeFormats };
VueI18n.prototype._getNumberFormats = function _getNumberFormats () { return this._vm.numberFormats };

VueI18n.prototype._warnDefault = function _warnDefault (locale, key, result, vm, values, interpolateMode) {
  if (!isNull(result)) { return result }
  if (this._missing) {
    var missingRet = this._missing.apply(null, [locale, key, vm, values]);
    if (isString(missingRet)) {
      return missingRet
    }
  } else {
    if (process.env.NODE_ENV !== 'production' && !this._isSilentTranslationWarn(key)) {
      warn(
        "Cannot translate the value of keypath '" + key + "'. " +
        'Use the value of keypath as default.'
      );
    }
  }

  if (this._formatFallbackMessages) {
    var parsedArgs = parseArgs.apply(void 0, values);
    return this._render(key, interpolateMode, parsedArgs.params, key)
  } else {
    return key
  }
};

VueI18n.prototype._isFallbackRoot = function _isFallbackRoot (val) {
  return !val && !isNull(this._root) && this._fallbackRoot
};

VueI18n.prototype._isSilentFallbackWarn = function _isSilentFallbackWarn (key) {
  return this._silentFallbackWarn instanceof RegExp
    ? this._silentFallbackWarn.test(key)
    : this._silentFallbackWarn
};

VueI18n.prototype._isSilentFallback = function _isSilentFallback (locale, key) {
  return this._isSilentFallbackWarn(key) && (this._isFallbackRoot() || locale !== this.fallbackLocale)
};

VueI18n.prototype._isSilentTranslationWarn = function _isSilentTranslationWarn (key) {
  return this._silentTranslationWarn instanceof RegExp
    ? this._silentTranslationWarn.test(key)
    : this._silentTranslationWarn
};

VueI18n.prototype._interpolate = function _interpolate (
  locale,
  message,
  key,
  host,
  interpolateMode,
  values,
  visitedLinkStack
) {
  if (!message) { return null }

  var pathRet = this._path.getPathValue(message, key);
  if (Array.isArray(pathRet) || isPlainObject(pathRet)) { return pathRet }

  var ret;
  if (isNull(pathRet)) {
    /* istanbul ignore else */
    if (isPlainObject(message)) {
      ret = message[key];
      if (!isString(ret)) {
        if (process.env.NODE_ENV !== 'production' && !this._isSilentTranslationWarn(key) && !this._isSilentFallback(locale, key)) {
          warn(("Value of key '" + key + "' is not a string!"));
        }
        return null
      }
    } else {
      return null
    }
  } else {
    /* istanbul ignore else */
    if (isString(pathRet)) {
      ret = pathRet;
    } else {
      if (process.env.NODE_ENV !== 'production' && !this._isSilentTranslationWarn(key) && !this._isSilentFallback(locale, key)) {
        warn(("Value of key '" + key + "' is not a string!"));
      }
      return null
    }
  }

  // Check for the existence of links within the translated string
  if (ret.indexOf('@:') >= 0 || ret.indexOf('@.') >= 0) {
    ret = this._link(locale, message, ret, host, 'raw', values, visitedLinkStack);
  }

  return this._render(ret, interpolateMode, values, key)
};

VueI18n.prototype._link = function _link (
  locale,
  message,
  str,
  host,
  interpolateMode,
  values,
  visitedLinkStack
) {
  var ret = str;

  // Match all the links within the local
  // We are going to replace each of
  // them with its translation
  var matches = ret.match(linkKeyMatcher);
  for (var idx in matches) {
    // ie compatible: filter custom array
    // prototype method
    if (!matches.hasOwnProperty(idx)) {
      continue
    }
    var link = matches[idx];
    var linkKeyPrefixMatches = link.match(linkKeyPrefixMatcher);
    var linkPrefix = linkKeyPrefixMatches[0];
      var formatterName = linkKeyPrefixMatches[1];

    // Remove the leading @:, @.case: and the brackets
    var linkPlaceholder = link.replace(linkPrefix, '').replace(bracketsMatcher, '');

    if (includes(visitedLinkStack, linkPlaceholder)) {
      if (process.env.NODE_ENV !== 'production') {
        warn(("Circular reference found. \"" + link + "\" is already visited in the chain of " + (visitedLinkStack.reverse().join(' <- '))));
      }
      return ret
    }
    visitedLinkStack.push(linkPlaceholder);

    // Translate the link
    var translated = this._interpolate(
      locale, message, linkPlaceholder, host,
      interpolateMode === 'raw' ? 'string' : interpolateMode,
      interpolateMode === 'raw' ? undefined : values,
      visitedLinkStack
    );

    if (this._isFallbackRoot(translated)) {
      if (process.env.NODE_ENV !== 'production' && !this._isSilentTranslationWarn(linkPlaceholder)) {
        warn(("Fall back to translate the link placeholder '" + linkPlaceholder + "' with root locale."));
      }
      /* istanbul ignore if */
      if (!this._root) { throw Error('unexpected error') }
      var root = this._root.$i18n;
      translated = root._translate(
        root._getMessages(), root.locale, root.fallbackLocale,
        linkPlaceholder, host, interpolateMode, values
      );
    }
    translated = this._warnDefault(
      locale, linkPlaceholder, translated, host,
      Array.isArray(values) ? values : [values],
      interpolateMode
    );

    if (this._modifiers.hasOwnProperty(formatterName)) {
      translated = this._modifiers[formatterName](translated);
    } else if (defaultModifiers.hasOwnProperty(formatterName)) {
      translated = defaultModifiers[formatterName](translated);
    }

    visitedLinkStack.pop();

    // Replace the link with the translated
    ret = !translated ? ret : ret.replace(link, translated);
  }

  return ret
};

VueI18n.prototype._render = function _render (message, interpolateMode, values, path) {
  var ret = this._formatter.interpolate(message, values, path);

  // If the custom formatter refuses to work - apply the default one
  if (!ret) {
    ret = defaultFormatter.interpolate(message, values, path);
  }

  // if interpolateMode is **not** 'string' ('row'),
  // return the compiled data (e.g. ['foo', VNode, 'bar']) with formatter
  return interpolateMode === 'string' && !isString(ret) ? ret.join('') : ret
};

VueI18n.prototype._appendItemToChain = function _appendItemToChain (chain, item, blocks) {
  var follow = false;
  if (!includes(chain, item)) {
    follow = true;
    if (item) {
      follow = item[item.length - 1] !== '!';
      item = item.replace(/!/g, '');
      chain.push(item);
      if (blocks && blocks[item]) {
        follow = blocks[item];
      }
    }
  }
  return follow
};

VueI18n.prototype._appendLocaleToChain = function _appendLocaleToChain (chain, locale, blocks) {
  var follow;
  var tokens = locale.split('-');
  do {
    var item = tokens.join('-');
    follow = this._appendItemToChain(chain, item, blocks);
    tokens.splice(-1, 1);
  } while (tokens.length && (follow === true))
  return follow
};

VueI18n.prototype._appendBlockToChain = function _appendBlockToChain (chain, block, blocks) {
  var follow = true;
  for (var i = 0; (i < block.length) && (isBoolean(follow)); i++) {
    var locale = block[i];
    if (isString(locale)) {
      follow = this._appendLocaleToChain(chain, locale, blocks);
    }
  }
  return follow
};

VueI18n.prototype._getLocaleChain = function _getLocaleChain (start, fallbackLocale) {
  if (start === '') { return [] }

  if (!this._localeChainCache) {
    this._localeChainCache = {};
  }

  var chain = this._localeChainCache[start];
  if (!chain) {
    if (!fallbackLocale) {
      fallbackLocale = this.fallbackLocale;
    }
    chain = [];

    // first block defined by start
    var block = [start];

    // while any intervening block found
    while (isArray(block)) {
      block = this._appendBlockToChain(
        chain,
        block,
        fallbackLocale
      );
    }

    // last block defined by default
    var defaults;
    if (isArray(fallbackLocale)) {
      defaults = fallbackLocale;
    } else if (isObject(fallbackLocale)) {
      /* $FlowFixMe */
      if (fallbackLocale['default']) {
        defaults = fallbackLocale['default'];
      } else {
        defaults = null;
      }
    } else {
      defaults = fallbackLocale;
    }

    // convert defaults to array
    if (isString(defaults)) {
      block = [defaults];
    } else {
      block = defaults;
    }
    if (block) {
      this._appendBlockToChain(
        chain,
        block,
        null
      );
    }
    this._localeChainCache[start] = chain;
  }
  return chain
};

VueI18n.prototype._translate = function _translate (
  messages,
  locale,
  fallback,
  key,
  host,
  interpolateMode,
  args
) {
  var chain = this._getLocaleChain(locale, fallback);
  var res;
  for (var i = 0; i < chain.length; i++) {
    var step = chain[i];
    res =
      this._interpolate(step, messages[step], key, host, interpolateMode, args, [key]);
    if (!isNull(res)) {
      if (step !== locale && process.env.NODE_ENV !== 'production' && !this._isSilentTranslationWarn(key) && !this._isSilentFallbackWarn(key)) {
        warn(("Fall back to translate the keypath '" + key + "' with '" + step + "' locale."));
      }
      return res
    }
  }
  return null
};

VueI18n.prototype._t = function _t (key, _locale, messages, host) {
    var ref;

    var values = [], len = arguments.length - 4;
    while ( len-- > 0 ) values[ len ] = arguments[ len + 4 ];
  if (!key) { return '' }

  var parsedArgs = parseArgs.apply(void 0, values);
  var locale = parsedArgs.locale || _locale;

  var ret = this._translate(
    messages, locale, this.fallbackLocale, key,
    host, 'string', parsedArgs.params
  );
  if (this._isFallbackRoot(ret)) {
    if (process.env.NODE_ENV !== 'production' && !this._isSilentTranslationWarn(key) && !this._isSilentFallbackWarn(key)) {
      warn(("Fall back to translate the keypath '" + key + "' with root locale."));
    }
    /* istanbul ignore if */
    if (!this._root) { throw Error('unexpected error') }
    return (ref = this._root).$t.apply(ref, [ key ].concat( values ))
  } else {
    ret = this._warnDefault(locale, key, ret, host, values, 'string');
    if (this._postTranslation && ret !== null && ret !== undefined) {
      ret = this._postTranslation(ret, key);
    }
    return ret
  }
};

VueI18n.prototype.t = function t (key) {
    var ref;

    var values = [], len = arguments.length - 1;
    while ( len-- > 0 ) values[ len ] = arguments[ len + 1 ];
  return (ref = this)._t.apply(ref, [ key, this.locale, this._getMessages(), null ].concat( values ))
};

VueI18n.prototype._i = function _i (key, locale, messages, host, values) {
  var ret =
    this._translate(messages, locale, this.fallbackLocale, key, host, 'raw', values);
  if (this._isFallbackRoot(ret)) {
    if (process.env.NODE_ENV !== 'production' && !this._isSilentTranslationWarn(key)) {
      warn(("Fall back to interpolate the keypath '" + key + "' with root locale."));
    }
    if (!this._root) { throw Error('unexpected error') }
    return this._root.$i18n.i(key, locale, values)
  } else {
    return this._warnDefault(locale, key, ret, host, [values], 'raw')
  }
};

VueI18n.prototype.i = function i (key, locale, values) {
  /* istanbul ignore if */
  if (!key) { return '' }

  if (!isString(locale)) {
    locale = this.locale;
  }

  return this._i(key, locale, this._getMessages(), null, values)
};

VueI18n.prototype._tc = function _tc (
  key,
  _locale,
  messages,
  host,
  choice
) {
    var ref;

    var values = [], len = arguments.length - 5;
    while ( len-- > 0 ) values[ len ] = arguments[ len + 5 ];
  if (!key) { return '' }
  if (choice === undefined) {
    choice = 1;
  }

  var predefined = { 'count': choice, 'n': choice };
  var parsedArgs = parseArgs.apply(void 0, values);
  parsedArgs.params = Object.assign(predefined, parsedArgs.params);
  values = parsedArgs.locale === null ? [parsedArgs.params] : [parsedArgs.locale, parsedArgs.params];
  return this.fetchChoice((ref = this)._t.apply(ref, [ key, _locale, messages, host ].concat( values )), choice)
};

VueI18n.prototype.fetchChoice = function fetchChoice (message, choice) {
  /* istanbul ignore if */
  if (!message && !isString(message)) { return null }
  var choices = message.split('|');

  choice = this.getChoiceIndex(choice, choices.length);
  if (!choices[choice]) { return message }
  return choices[choice].trim()
};

VueI18n.prototype.tc = function tc (key, choice) {
    var ref;

    var values = [], len = arguments.length - 2;
    while ( len-- > 0 ) values[ len ] = arguments[ len + 2 ];
  return (ref = this)._tc.apply(ref, [ key, this.locale, this._getMessages(), null, choice ].concat( values ))
};

VueI18n.prototype._te = function _te (key, locale, messages) {
    var args = [], len = arguments.length - 3;
    while ( len-- > 0 ) args[ len ] = arguments[ len + 3 ];

  var _locale = parseArgs.apply(void 0, args).locale || locale;
  return this._exist(messages[_locale], key)
};

VueI18n.prototype.te = function te (key, locale) {
  return this._te(key, this.locale, this._getMessages(), locale)
};

VueI18n.prototype.getLocaleMessage = function getLocaleMessage (locale) {
  return looseClone(this._vm.messages[locale] || {})
};

VueI18n.prototype.setLocaleMessage = function setLocaleMessage (locale, message) {
  if (this._warnHtmlInMessage === 'warn' || this._warnHtmlInMessage === 'error') {
    this._checkLocaleMessage(locale, this._warnHtmlInMessage, message);
  }
  this._vm.$set(this._vm.messages, locale, message);
};

VueI18n.prototype.mergeLocaleMessage = function mergeLocaleMessage (locale, message) {
  if (this._warnHtmlInMessage === 'warn' || this._warnHtmlInMessage === 'error') {
    this._checkLocaleMessage(locale, this._warnHtmlInMessage, message);
  }
  this._vm.$set(this._vm.messages, locale, merge({}, this._vm.messages[locale] || {}, message));
};

VueI18n.prototype.getDateTimeFormat = function getDateTimeFormat (locale) {
  return looseClone(this._vm.dateTimeFormats[locale] || {})
};

VueI18n.prototype.setDateTimeFormat = function setDateTimeFormat (locale, format) {
  this._vm.$set(this._vm.dateTimeFormats, locale, format);
  this._clearDateTimeFormat(locale, format);
};

VueI18n.prototype.mergeDateTimeFormat = function mergeDateTimeFormat (locale, format) {
  this._vm.$set(this._vm.dateTimeFormats, locale, merge(this._vm.dateTimeFormats[locale] || {}, format));
  this._clearDateTimeFormat(locale, format);
};

VueI18n.prototype._clearDateTimeFormat = function _clearDateTimeFormat (locale, format) {
  for (var key in format) {
    var id = locale + "__" + key;

    if (!this._dateTimeFormatters.hasOwnProperty(id)) {
      continue
    }

    delete this._dateTimeFormatters[id];
  }
};

VueI18n.prototype._localizeDateTime = function _localizeDateTime (
  value,
  locale,
  fallback,
  dateTimeFormats,
  key
) {
  var _locale = locale;
  var formats = dateTimeFormats[_locale];

  var chain = this._getLocaleChain(locale, fallback);
  for (var i = 0; i < chain.length; i++) {
    var current = _locale;
    var step = chain[i];
    formats = dateTimeFormats[step];
    _locale = step;
    // fallback locale
    if (isNull(formats) || isNull(formats[key])) {
      if (step !== locale && process.env.NODE_ENV !== 'production' && !this._isSilentTranslationWarn(key) && !this._isSilentFallbackWarn(key)) {
        warn(("Fall back to '" + step + "' datetime formats from '" + current + "' datetime formats."));
      }
    } else {
      break
    }
  }

  if (isNull(formats) || isNull(formats[key])) {
    return null
  } else {
    var format = formats[key];
    var id = _locale + "__" + key;
    var formatter = this._dateTimeFormatters[id];
    if (!formatter) {
      formatter = this._dateTimeFormatters[id] = new Intl.DateTimeFormat(_locale, format);
    }
    return formatter.format(value)
  }
};

VueI18n.prototype._d = function _d (value, locale, key) {
  /* istanbul ignore if */
  if (process.env.NODE_ENV !== 'production' && !VueI18n.availabilities.dateTimeFormat) {
    warn('Cannot format a Date value due to not supported Intl.DateTimeFormat.');
    return ''
  }

  if (!key) {
    return new Intl.DateTimeFormat(locale).format(value)
  }

  var ret =
    this._localizeDateTime(value, locale, this.fallbackLocale, this._getDateTimeFormats(), key);
  if (this._isFallbackRoot(ret)) {
    if (process.env.NODE_ENV !== 'production' && !this._isSilentTranslationWarn(key) && !this._isSilentFallbackWarn(key)) {
      warn(("Fall back to datetime localization of root: key '" + key + "'."));
    }
    /* istanbul ignore if */
    if (!this._root) { throw Error('unexpected error') }
    return this._root.$i18n.d(value, key, locale)
  } else {
    return ret || ''
  }
};

VueI18n.prototype.d = function d (value) {
    var args = [], len = arguments.length - 1;
    while ( len-- > 0 ) args[ len ] = arguments[ len + 1 ];

  var locale = this.locale;
  var key = null;

  if (args.length === 1) {
    if (isString(args[0])) {
      key = args[0];
    } else if (isObject(args[0])) {
      if (args[0].locale) {
        locale = args[0].locale;
      }
      if (args[0].key) {
        key = args[0].key;
      }
    }
  } else if (args.length === 2) {
    if (isString(args[0])) {
      key = args[0];
    }
    if (isString(args[1])) {
      locale = args[1];
    }
  }

  return this._d(value, locale, key)
};

VueI18n.prototype.getNumberFormat = function getNumberFormat (locale) {
  return looseClone(this._vm.numberFormats[locale] || {})
};

VueI18n.prototype.setNumberFormat = function setNumberFormat (locale, format) {
  this._vm.$set(this._vm.numberFormats, locale, format);
  this._clearNumberFormat(locale, format);
};

VueI18n.prototype.mergeNumberFormat = function mergeNumberFormat (locale, format) {
  this._vm.$set(this._vm.numberFormats, locale, merge(this._vm.numberFormats[locale] || {}, format));
  this._clearNumberFormat(locale, format);
};

VueI18n.prototype._clearNumberFormat = function _clearNumberFormat (locale, format) {
  for (var key in format) {
    var id = locale + "__" + key;

    if (!this._numberFormatters.hasOwnProperty(id)) {
      continue
    }

    delete this._numberFormatters[id];
  }
};

VueI18n.prototype._getNumberFormatter = function _getNumberFormatter (
  value,
  locale,
  fallback,
  numberFormats,
  key,
  options
) {
  var _locale = locale;
  var formats = numberFormats[_locale];

  var chain = this._getLocaleChain(locale, fallback);
  for (var i = 0; i < chain.length; i++) {
    var current = _locale;
    var step = chain[i];
    formats = numberFormats[step];
    _locale = step;
    // fallback locale
    if (isNull(formats) || isNull(formats[key])) {
      if (step !== locale && process.env.NODE_ENV !== 'production' && !this._isSilentTranslationWarn(key) && !this._isSilentFallbackWarn(key)) {
        warn(("Fall back to '" + step + "' number formats from '" + current + "' number formats."));
      }
    } else {
      break
    }
  }

  if (isNull(formats) || isNull(formats[key])) {
    return null
  } else {
    var format = formats[key];

    var formatter;
    if (options) {
      // If options specified - create one time number formatter
      formatter = new Intl.NumberFormat(_locale, Object.assign({}, format, options));
    } else {
      var id = _locale + "__" + key;
      formatter = this._numberFormatters[id];
      if (!formatter) {
        formatter = this._numberFormatters[id] = new Intl.NumberFormat(_locale, format);
      }
    }
    return formatter
  }
};

VueI18n.prototype._n = function _n (value, locale, key, options) {
  /* istanbul ignore if */
  if (!VueI18n.availabilities.numberFormat) {
    if (process.env.NODE_ENV !== 'production') {
      warn('Cannot format a Number value due to not supported Intl.NumberFormat.');
    }
    return ''
  }

  if (!key) {
    var nf = !options ? new Intl.NumberFormat(locale) : new Intl.NumberFormat(locale, options);
    return nf.format(value)
  }

  var formatter = this._getNumberFormatter(value, locale, this.fallbackLocale, this._getNumberFormats(), key, options);
  var ret = formatter && formatter.format(value);
  if (this._isFallbackRoot(ret)) {
    if (process.env.NODE_ENV !== 'production' && !this._isSilentTranslationWarn(key) && !this._isSilentFallbackWarn(key)) {
      warn(("Fall back to number localization of root: key '" + key + "'."));
    }
    /* istanbul ignore if */
    if (!this._root) { throw Error('unexpected error') }
    return this._root.$i18n.n(value, Object.assign({}, { key: key, locale: locale }, options))
  } else {
    return ret || ''
  }
};

VueI18n.prototype.n = function n (value) {
    var args = [], len = arguments.length - 1;
    while ( len-- > 0 ) args[ len ] = arguments[ len + 1 ];

  var locale = this.locale;
  var key = null;
  var options = null;

  if (args.length === 1) {
    if (isString(args[0])) {
      key = args[0];
    } else if (isObject(args[0])) {
      if (args[0].locale) {
        locale = args[0].locale;
      }
      if (args[0].key) {
        key = args[0].key;
      }

      // Filter out number format options only
      options = Object.keys(args[0]).reduce(function (acc, key) {
          var obj;

        if (includes(numberFormatKeys, key)) {
          return Object.assign({}, acc, ( obj = {}, obj[key] = args[0][key], obj ))
        }
        return acc
      }, null);
    }
  } else if (args.length === 2) {
    if (isString(args[0])) {
      key = args[0];
    }
    if (isString(args[1])) {
      locale = args[1];
    }
  }

  return this._n(value, locale, key, options)
};

VueI18n.prototype._ntp = function _ntp (value, locale, key, options) {
  /* istanbul ignore if */
  if (!VueI18n.availabilities.numberFormat) {
    if (process.env.NODE_ENV !== 'production') {
      warn('Cannot format to parts a Number value due to not supported Intl.NumberFormat.');
    }
    return []
  }

  if (!key) {
    var nf = !options ? new Intl.NumberFormat(locale) : new Intl.NumberFormat(locale, options);
    return nf.formatToParts(value)
  }

  var formatter = this._getNumberFormatter(value, locale, this.fallbackLocale, this._getNumberFormats(), key, options);
  var ret = formatter && formatter.formatToParts(value);
  if (this._isFallbackRoot(ret)) {
    if (process.env.NODE_ENV !== 'production' && !this._isSilentTranslationWarn(key)) {
      warn(("Fall back to format number to parts of root: key '" + key + "' ."));
    }
    /* istanbul ignore if */
    if (!this._root) { throw Error('unexpected error') }
    return this._root.$i18n._ntp(value, locale, key, options)
  } else {
    return ret || []
  }
};

Object.defineProperties( VueI18n.prototype, prototypeAccessors );

var availabilities;
// $FlowFixMe
Object.defineProperty(VueI18n, 'availabilities', {
  get: function get () {
    if (!availabilities) {
      var intlDefined = typeof Intl !== 'undefined';
      availabilities = {
        dateTimeFormat: intlDefined && typeof Intl.DateTimeFormat !== 'undefined',
        numberFormat: intlDefined && typeof Intl.NumberFormat !== 'undefined'
      };
    }

    return availabilities
  }
});

VueI18n.install = install;
VueI18n.version = '8.20.0';

module.exports = VueI18n;