129 lines
3.1 KiB
JavaScript

'use strict';
// We have an ES6 Map available, return the native instance
if (typeof global.Map !== 'undefined') {
module.exports = global.Map;
module.exports.Map = global.Map;
} else {
// We will return a polyfill
var Map = function(array) {
this._keys = [];
this._values = {};
for (var i = 0; i < array.length; i++) {
if (array[i] == null) continue; // skip null and undefined
var entry = array[i];
var key = entry[0];
var value = entry[1];
// Add the key to the list of keys in order
this._keys.push(key);
// Add the key and value to the values dictionary with a point
// to the location in the ordered keys list
this._values[key] = { v: value, i: this._keys.length - 1 };
}
};
Map.prototype.clear = function() {
this._keys = [];
this._values = {};
};
Map.prototype.delete = function(key) {
var value = this._values[key];
if (value == null) return false;
// Delete entry
delete this._values[key];
// Remove the key from the ordered keys list
this._keys.splice(value.i, 1);
return true;
};
Map.prototype.entries = function() {
var self = this;
var index = 0;
return {
next: function() {
var key = self._keys[index++];
return {
value: key !== undefined ? [key, self._values[key].v] : undefined,
done: key !== undefined ? false : true
};
}
};
};
Map.prototype.forEach = function(callback, self) {
self = self || this;
for (var i = 0; i < this._keys.length; i++) {
var key = this._keys[i];
// Call the forEach callback
callback.call(self, this._values[key].v, key, self);
}
};
Map.prototype.get = function(key) {
return this._values[key] ? this._values[key].v : undefined;
};
Map.prototype.has = function(key) {
return this._values[key] != null;
};
Map.prototype.keys = function() {
var self = this;
var index = 0;
return {
next: function() {
var key = self._keys[index++];
return {
value: key !== undefined ? key : undefined,
done: key !== undefined ? false : true
};
}
};
};
Map.prototype.set = function(key, value) {
if (this._values[key]) {
this._values[key].v = value;
return this;
}
// Add the key to the list of keys in order
this._keys.push(key);
// Add the key and value to the values dictionary with a point
// to the location in the ordered keys list
this._values[key] = { v: value, i: this._keys.length - 1 };
return this;
};
Map.prototype.values = function() {
var self = this;
var index = 0;
return {
next: function() {
var key = self._keys[index++];
return {
value: key !== undefined ? self._values[key].v : undefined,
done: key !== undefined ? false : true
};
}
};
};
// Last ismaster
Object.defineProperty(Map.prototype, 'size', {
enumerable: true,
get: function() {
return this._keys.length;
}
});
module.exports = Map;
module.exports.Map = Map;
}