Preliminary Harmony weak maps API implementation.

src/weakmap.js

+// Copyright 2011 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+
+// This file relies on the fact that the following declaration has been made
+// in runtime.js:
+// const $Object = global.Object;
+const $WeakMap = global.WeakMap;
+
+// -------------------------------------------------------------------
+
+// Set the WeakMap function and constructor.
+%SetCode($WeakMap, function(x) {
+  return %WeakMapCreate(this);
+});
+
+
+function WeakMapGet(key) {
+  if (!IS_OBJECT(key)) {
+    throw %MakeTypeError('invalid_weakmap_key', [this, key]);
+  }
+  return %WeakMapGet(this, key);
+}
+
+
+function WeakMapSet(key, value) {
+  if (!IS_OBJECT(key)) {
+    throw %MakeTypeError('invalid_weakmap_key', [this, key]);
+  }
+  return %WeakMapSet(this, key, value);
+}
+
+// -------------------------------------------------------------------
+
+function SetupWeakMap() {
+  // Setup the constructor property on the WeakMap prototype object.
+  //%SetProperty($WeakMap.prototype, "constructor", $WeakMap, DONT_ENUM);
+
+  // Setup the non-enumerable functions on the WeakMap prototype object.
+  InstallFunctionsOnHiddenPrototype($WeakMap.prototype, DONT_ENUM, $Array(
+    "get", WeakMapGet,
+    "set", WeakMapSet
+  ));
+}
+
+
+SetupWeakMap();