The Tor Browser / file diff

     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/addon-sdk/source/lib/sdk/core/namespace.js	Wed Dec 31 06:09:35 2014 +0100
     1.3 @@ -0,0 +1,43 @@
     1.4 +/* This Source Code Form is subject to the terms of the Mozilla Public
     1.5 + * License, v. 2.0. If a copy of the MPL was not distributed with this
     1.6 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
     1.7 +
     1.8 +"use strict";
     1.9 +
    1.10 +module.metadata = {
    1.11 +  "stability": "unstable"
    1.12 +};
    1.13 +
    1.14 +const create = Object.create;
    1.15 +const prototypeOf = Object.getPrototypeOf;
    1.16 +
    1.17 +/**
    1.18 + * Returns a new namespace, function that may can be used to access an
    1.19 + * namespaced object of the argument argument. Namespaced object are associated
    1.20 + * with owner objects via weak references. Namespaced objects inherit from the
    1.21 + * owners ancestor namespaced object. If owner's ancestor is `null` then
    1.22 + * namespaced object inherits from given `prototype`. Namespaces can be used
    1.23 + * to define internal APIs that can be shared via enclosing `namespace`
    1.24 + * function.
    1.25 + * @examples
    1.26 + *    const internals = ns();
    1.27 + *    internals(object).secret = secret;
    1.28 + */
    1.29 +function ns() {
    1.30 +  const map = new WeakMap();
    1.31 +  return function namespace(target) {
    1.32 +    if (!target)        // If `target` is not an object return `target` itself.
    1.33 +      return target;
    1.34 +    // If target has no namespaced object yet, create one that inherits from
    1.35 +    // the target prototype's namespaced object.
    1.36 +    if (!map.has(target))
    1.37 +      map.set(target, create(namespace(prototypeOf(target) || null)));
    1.38 +
    1.39 +    return map.get(target);
    1.40 +  };
    1.41 +};
    1.42 +
    1.43 +// `Namespace` is a e4x function in the scope, so we export the function also as
    1.44 +// `ns` as alias to avoid clashing.
    1.45 +exports.ns = ns;
    1.46 +exports.Namespace = ns;