Add abstract references base #205

lib/6to5/polyfill.js

@@ -1,6 +1,35 @@
+//
+
+var ensureSymbol = function (key) {
+  Symbol[key] = Symbol[key] || Symbol();
+};
+
+var ensureProto = function (Constructor, key, val) {
+  var proto = Constructor.prototype;
+  proto[key] = proto[key] || val;
+};
+
+//
+
 if (typeof Symbol === "undefined") {
   require("es6-symbol/implement");
 }
 
 require("es6-shim");
 require("./transformation/transformers/generators/runtime");
+
+// 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);
+
+ensureProto(WeakMap, Symbol.referenceGet, WeakMap.prototype.get);
+ensureProto(WeakMap, Symbol.referenceSet, WeakMap.prototype.set);
+ensureProto(WeakMap, Symbol.referenceDelete, WeakMap.prototype.delete);

lib/6to5/transformation/transform.js

@@ -47,6 +47,7 @@ _.each({
   forOf:                     require("./transformers/for-of"),
   unicodeRegex:              require("./transformers/unicode-regex"),
   react:                     require("./transformers/react"),
+  abstractReferences:        require("./transformers/abstract-references"),
 
   constants:                 require("./transformers/constants"),
   letScoping:                require("./transformers/let-scoping"),