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1/**2 * Mnemonist FuzzyMultiMap3 * ========================4 *5 * Same as the fuzzy map but relying on a MultiMap rather than a Map.6 */7var MultiMap = require('./multi-map.js'),8    forEach = require('obliterator/foreach');9 10var identity = function(x) {11  return x;12};13 14/**15 * FuzzyMultiMap.16 *17 * @constructor18 * @param {array|function} descriptor - Hash functions descriptor.19 * @param {function}       Container  - Container to use.20 */21function FuzzyMultiMap(descriptor, Container) {22  this.items = new MultiMap(Container);23  this.clear();24 25  if (Array.isArray(descriptor)) {26    this.writeHashFunction = descriptor[0];27    this.readHashFunction = descriptor[1];28  }29  else {30    this.writeHashFunction = descriptor;31    this.readHashFunction = descriptor;32  }33 34  if (!this.writeHashFunction)35    this.writeHashFunction = identity;36  if (!this.readHashFunction)37    this.readHashFunction = identity;38 39  if (typeof this.writeHashFunction !== 'function')40    throw new Error('mnemonist/FuzzyMultiMap.constructor: invalid hash function given.');41 42  if (typeof this.readHashFunction !== 'function')43    throw new Error('mnemonist/FuzzyMultiMap.constructor: invalid hash function given.');44}45 46/**47 * Method used to clear the structure.48 *49 * @return {undefined}50 */51FuzzyMultiMap.prototype.clear = function() {52  this.items.clear();53 54  // Properties55  this.size = 0;56  this.dimension = 0;57};58 59/**60 * Method used to add an item to the index.61 *62 * @param  {any} item - Item to add.63 * @return {FuzzyMultiMap}64 */65FuzzyMultiMap.prototype.add = function(item) {66  var key = this.writeHashFunction(item);67 68  this.items.set(key, item);69  this.size = this.items.size;70  this.dimension = this.items.dimension;71 72  return this;73};74 75/**76 * Method used to set an item in the index using the given key.77 *78 * @param  {any} key  - Key to use.79 * @param  {any} item - Item to add.80 * @return {FuzzyMultiMap}81 */82FuzzyMultiMap.prototype.set = function(key, item) {83  key = this.writeHashFunction(key);84 85  this.items.set(key, item);86  this.size = this.items.size;87  this.dimension = this.items.dimension;88 89  return this;90};91 92/**93 * Method used to retrieve an item from the index.94 *95 * @param  {any} key - Key to use.96 * @return {any}97 */98FuzzyMultiMap.prototype.get = function(key) {99  key = this.readHashFunction(key);100 101  return this.items.get(key);102};103 104/**105 * Method used to test the existence of an item in the map.106 *107 * @param  {any} key - Key to check.108 * @return {boolean}109 */110FuzzyMultiMap.prototype.has = function(key) {111  key = this.readHashFunction(key);112 113  return this.items.has(key);114};115 116/**117 * Method used to iterate over each of the index's values.118 *119 * @param  {function}  callback - Function to call for each item.120 * @param  {object}    scope    - Optional scope.121 * @return {undefined}122 */123FuzzyMultiMap.prototype.forEach = function(callback, scope) {124  scope = arguments.length > 1 ? scope : this;125 126  this.items.forEach(function(value) {127    callback.call(scope, value, value);128  });129};130 131/**132 * Method returning an iterator over the index's values.133 *134 * @return {FuzzyMultiMapIterator}135 */136FuzzyMultiMap.prototype.values = function() {137  return this.items.values();138};139 140/**141 * Attaching the #.values method to Symbol.iterator if possible.142 */143if (typeof Symbol !== 'undefined')144  FuzzyMultiMap.prototype[Symbol.iterator] = FuzzyMultiMap.prototype.values;145 146/**147 * Convenience known method.148 */149FuzzyMultiMap.prototype.inspect = function() {150  var array = Array.from(this);151 152  Object.defineProperty(array, 'constructor', {153    value: FuzzyMultiMap,154    enumerable: false155  });156 157  return array;158};159 160if (typeof Symbol !== 'undefined')161  FuzzyMultiMap.prototype[Symbol.for('nodejs.util.inspect.custom')] = FuzzyMultiMap.prototype.inspect;162 163/**164 * Static @.from function taking an arbitrary iterable & converting it into165 * a structure.166 *167 * @param  {Iterable}       iterable   - Target iterable.168 * @param  {array|function} descriptor - Hash functions descriptor.169 * @param  {function}       Container  - Container to use.170 * @param  {boolean}        useSet     - Whether to use #.set or #.add171 * @return {FuzzyMultiMap}172 */173FuzzyMultiMap.from = function(iterable, descriptor, Container, useSet) {174  if (arguments.length === 3) {175    if (typeof Container === 'boolean') {176      useSet = Container;177      Container = Array;178    }179  }180 181  var map = new FuzzyMultiMap(descriptor, Container);182 183  forEach(iterable, function(value, key) {184    if (useSet)185      map.set(key, value);186    else187      map.add(value);188  });189 190  return map;191};192 193/**194 * Exporting.195 */196module.exports = FuzzyMultiMap;197