addon-sdk/source/lib/sdk/core/namespace.js@6474c204b198 (annotated)
addon-sdk/source/lib/sdk/core/namespace.js
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
| michael@0 | 1 | /* This Source Code Form is subject to the terms of the Mozilla Public |
| michael@0 | 2 | * License, v. 2.0. If a copy of the MPL was not distributed with this |
| michael@0 | 3 | * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| michael@0 | 4 | |
| michael@0 | 5 | "use strict"; |
| michael@0 | 6 | |
| michael@0 | 7 | module.metadata = { |
| michael@0 | 8 | "stability": "unstable" |
| michael@0 | 9 | }; |
| michael@0 | 10 | |
| michael@0 | 11 | const create = Object.create; |
| michael@0 | 12 | const prototypeOf = Object.getPrototypeOf; |
| michael@0 | 13 | |
| michael@0 | 14 | /** |
| michael@0 | 15 | * Returns a new namespace, function that may can be used to access an |
| michael@0 | 16 | * namespaced object of the argument argument. Namespaced object are associated |
| michael@0 | 17 | * with owner objects via weak references. Namespaced objects inherit from the |
| michael@0 | 18 | * owners ancestor namespaced object. If owner's ancestor is `null` then |
| michael@0 | 19 | * namespaced object inherits from given `prototype`. Namespaces can be used |
| michael@0 | 20 | * to define internal APIs that can be shared via enclosing `namespace` |
| michael@0 | 21 | * function. |
| michael@0 | 22 | * @examples |
| michael@0 | 23 | * const internals = ns(); |
| michael@0 | 24 | * internals(object).secret = secret; |
| michael@0 | 25 | */ |
| michael@0 | 26 | function ns() { |
| michael@0 | 27 | const map = new WeakMap(); |
| michael@0 | 28 | return function namespace(target) { |
| michael@0 | 29 | if (!target) // If `target` is not an object return `target` itself. |
| michael@0 | 30 | return target; |
| michael@0 | 31 | // If target has no namespaced object yet, create one that inherits from |
| michael@0 | 32 | // the target prototype's namespaced object. |
| michael@0 | 33 | if (!map.has(target)) |
| michael@0 | 34 | map.set(target, create(namespace(prototypeOf(target) || null))); |
| michael@0 | 35 | |
| michael@0 | 36 | return map.get(target); |
| michael@0 | 37 | }; |
| michael@0 | 38 | }; |
| michael@0 | 39 | |
| michael@0 | 40 | // `Namespace` is a e4x function in the scope, so we export the function also as |
| michael@0 | 41 | // `ns` as alias to avoid clashing. |
| michael@0 | 42 | exports.ns = ns; |
| michael@0 | 43 | exports.Namespace = ns; |
