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Diffstat (limited to 'tools/addon-sdk-1.5/packages/api-utils/lib/array.js')
-rw-r--r-- | tools/addon-sdk-1.5/packages/api-utils/lib/array.js | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/tools/addon-sdk-1.5/packages/api-utils/lib/array.js b/tools/addon-sdk-1.5/packages/api-utils/lib/array.js new file mode 100644 index 0000000..dadcfa6 --- /dev/null +++ b/tools/addon-sdk-1.5/packages/api-utils/lib/array.js @@ -0,0 +1,69 @@ +/* vim:set ts=2 sw=2 sts=2 et: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +"use strict"; + +/** + * Returns `true` if given `array` contain given `element` or `false` + * otherwise. + * @param {Array} array + * Target array. + * @param {Object|String|Number|Boolean} element + * Element being looked up. + * @returns {Boolean} + */ +var has = exports.has = function has(array, element) { + // shorter and faster equivalent of `array.indexOf(element) >= 0` + return !!~array.indexOf(element); +}; + +/** + * Adds given `element` to the given `array` if it does not contain it yet. + * `true` is returned if element was added otherwise `false` is returned. + * @param {Array} array + * Target array. + * @param {Object|String|Number|Boolean} element + * Element to be added. + * @returns {Boolean} + */ +var add = exports.add = function add(array, element) { + var result; + if ((result = !has(array, element))) + array.push(element); + + return result; +}; + +/** + * Removes first occurrence of the given `element` from the given `array`. If + * `array` does not contain given `element` `false` is returned otherwise + * `true` is returned. + * @param {Array} array + * Target array. + * @param {Object|String|Number|Boolean} element + * Element to be removed. + * @returns {Boolean} + */ +exports.remove = function remove(array, element) { + var result; + if ((result = has(array, element))) + array.splice(array.indexOf(element), 1); + + return result; +}; + +/** + * Produces a duplicate-free version of the given `array`. + * @param {Array} array + * Source array. + * @returns {Array} + */ +exports.unique = function unique(array) { + var value = []; + return array.forEach(function(element) { + add(value, element); + }); + return value; +}; |