babel/lib/6to5/polyfill.js
2014-12-10 21:12:01 +11:00

52 lines
1.3 KiB
JavaScript

/* jshint newcap: false */
var ensureSymbol = function (key) {
Symbol[key] = Symbol[key] || Symbol(key);
};
var ensureProto = function (Constructor, key, val) {
var proto = Constructor.prototype;
proto[key] = proto[key] || val;
};
//
if (typeof Symbol === "undefined") {
require("es6-symbol/implement");
var globSymbols = {};
Symbol.for = function (key) {
return globSymbols[key] = globSymbols[key] || Symbol(key);
};
Symbol.keyFor = function (sym) {
return sym.__description__;
};
}
require("es6-shim");
require("./transformation/transformers/es6-generators/runtime");
ensureSymbol("species");
String.prototype.includes = String.prototype.includes || String.prototype.contains;
// Abstract references
ensureSymbol("referenceGet");
ensureSymbol("referenceSet");
ensureSymbol("referenceDelete");
ensureProto(Function, Symbol.referenceGet, function () { return this; });
ensureProto(Map, Symbol.referenceGet, Map.prototype.get);
ensureProto(Map, Symbol.referenceSet, Map.prototype.set);
ensureProto(Map, Symbol.referenceDelete, Map.prototype.delete);
if (global.WeakMap) {
ensureProto(WeakMap, Symbol.referenceGet, WeakMap.prototype.get);
ensureProto(WeakMap, Symbol.referenceSet, WeakMap.prototype.set);
ensureProto(WeakMap, Symbol.referenceDelete, WeakMap.prototype.delete);
}