weak-dictionary/src/index.js

Universal ES6-compatible WeakMap wrapper

var WeakDictionary = function() {
  this._weakMap = new WeakMap();
  this._keys = [];
};

WeakDictionary.prototype.set = function(key, value) {
  this._keys.push(key);
  return this._weakMap.set(key, value);
};

WeakDictionary.prototype.has = function(key) {
  return this._weakMap.has(key);
};

WeakDictionary.prototype.get = function(key) {
  return this._weakMap.get(key);
};

WeakDictionary.prototype.delete = function(key) {
  var result = this._weakMap.delete(key);
  this._keys.splice(this._keys.indexOf(key), 1);
  return result;
};

WeakDictionary.prototype.forEach = function(cb) {
  var that = this;
  this._keys.forEach(function(key) {
    if (that.has(key))
      cb(key, that.get(key));
  });
};

WeakDictionary.prototype.clear = function() {
  var that = this;
  this._keys.forEach(function(key) {
    if (that.has(key)) {
      var value = that.get(key);
      if (value)
        that.delete(key);
    }
  });
  this._weakMap = new WeakMap();
  this._keys = [];
};

WeakDictionary.prototype.getKeys = function() {
  return this._keys;
};

WeakDictionary.prototype.getSize = function() {
  this.refresh();
  return this._keys.length;
};

WeakDictionary.prototype.refresh = function() {
  var that = this;
  var keysToRemove = [];
  this._keys.forEach(function(key) {
    if (!that.has(key)) {
      keysToRemove.push(key);
    }
  });
};

module.exports = WeakDictionary;