addon-sdk/source/lib/sdk/util/dispatcher.js@129ffea94266 (annotated)
addon-sdk/source/lib/sdk/util/dispatcher.js
Sat, 03 Jan 2015 20:18:00 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Sat, 03 Jan 2015 20:18:00 +0100
- branch
- TOR_BUG_3246
- changeset 7
- 129ffea94266
- permissions
- -rw-r--r--
Conditionally enable double key logic according to:
private browsing mode or privacy.thirdparty.isolate preference and
implement in GetCookieStringCommon and FindCookie where it counts...
With some reservations of how to convince FindCookie users to test
condition and pass a nullptr when disabling double key logic.
| 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": "experimental" |
| michael@0 | 9 | }; |
| michael@0 | 10 | |
| michael@0 | 11 | const method = require("method/core"); |
| michael@0 | 12 | |
| michael@0 | 13 | // Utility function that is just an enhancement over `method` to |
| michael@0 | 14 | // allow predicate based dispatch in addition to polymorphic |
| michael@0 | 15 | // dispatch. Unfortunately polymorphic dispatch does not quite |
| michael@0 | 16 | // cuts it in the world of XPCOM where no types / classes exist |
| michael@0 | 17 | // and all the XUL nodes share same type / prototype. |
| michael@0 | 18 | // Probably this is more generic and belongs some place else, but |
| michael@0 | 19 | // we can move it later once this will be relevant. |
| michael@0 | 20 | let dispatcher = hint => { |
| michael@0 | 21 | const base = method(hint); |
| michael@0 | 22 | // Make a map for storing predicate, implementation mappings. |
| michael@0 | 23 | let implementations = new Map(); |
| michael@0 | 24 | |
| michael@0 | 25 | // Dispatcher function goes through `predicate, implementation` |
| michael@0 | 26 | // pairs to find predicate that matches first argument and |
| michael@0 | 27 | // returns application of arguments on the associated |
| michael@0 | 28 | // `implementation`. If no matching predicate is found delegates |
| michael@0 | 29 | // to a `base` polymorphic function. |
| michael@0 | 30 | let dispatch = (value, ...rest) => { |
| michael@0 | 31 | for (let [predicate, implementation] of implementations) { |
| michael@0 | 32 | if (predicate(value)) |
| michael@0 | 33 | return implementation(value, ...rest); |
| michael@0 | 34 | } |
| michael@0 | 35 | |
| michael@0 | 36 | return base(value, ...rest); |
| michael@0 | 37 | }; |
| michael@0 | 38 | |
| michael@0 | 39 | // Expose base API. |
| michael@0 | 40 | dispatch.define = base.define; |
| michael@0 | 41 | dispatch.implement = base.implement; |
| michael@0 | 42 | dispatch.toString = base.toString; |
| michael@0 | 43 | |
| michael@0 | 44 | // Add a `when` function to allow extending function via |
| michael@0 | 45 | // predicates. |
| michael@0 | 46 | dispatch.when = (predicate, implementation) => { |
| michael@0 | 47 | if (implementations.has(predicate)) |
| michael@0 | 48 | throw TypeError("Already implemented for the given predicate"); |
| michael@0 | 49 | implementations.set(predicate, implementation); |
| michael@0 | 50 | }; |
| michael@0 | 51 | |
| michael@0 | 52 | return dispatch; |
| michael@0 | 53 | }; |
| michael@0 | 54 | |
| michael@0 | 55 | exports.dispatcher = dispatcher; |
