67 lines
2.3 KiB
JavaScript
67 lines
2.3 KiB
JavaScript
/**
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* lodash 3.6.1 (Custom Build) <https://lodash.com/>
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* Build: `lodash modern modularize exports="npm" -o ./`
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* Copyright 2012-2015 The Dojo Foundation <http://dojofoundation.org/>
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* Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE>
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* Copyright 2009-2015 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
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* Available under MIT license <https://lodash.com/license>
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*/
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/** Used as the `TypeError` message for "Functions" methods. */
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var FUNC_ERROR_TEXT = 'Expected a function';
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/* Native method references for those with the same name as other `lodash` methods. */
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var nativeMax = Math.max;
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/**
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* Creates a function that invokes `func` with the `this` binding of the
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* created function and arguments from `start` and beyond provided as an array.
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*
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* **Note:** This method is based on the [rest parameter](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/rest_parameters).
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*
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* @static
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* @memberOf _
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* @category Function
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* @param {Function} func The function to apply a rest parameter to.
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* @param {number} [start=func.length-1] The start position of the rest parameter.
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* @returns {Function} Returns the new function.
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* @example
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*
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* var say = _.restParam(function(what, names) {
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* return what + ' ' + _.initial(names).join(', ') +
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* (_.size(names) > 1 ? ', & ' : '') + _.last(names);
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* });
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*
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* say('hello', 'fred', 'barney', 'pebbles');
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* // => 'hello fred, barney, & pebbles'
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*/
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function restParam(func, start) {
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if (typeof func != 'function') {
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throw new TypeError(FUNC_ERROR_TEXT);
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}
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start = nativeMax(start === undefined ? (func.length - 1) : (+start || 0), 0);
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return function() {
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var args = arguments,
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index = -1,
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length = nativeMax(args.length - start, 0),
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rest = Array(length);
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while (++index < length) {
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rest[index] = args[start + index];
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}
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switch (start) {
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case 0: return func.call(this, rest);
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case 1: return func.call(this, args[0], rest);
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case 2: return func.call(this, args[0], args[1], rest);
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}
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var otherArgs = Array(start + 1);
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index = -1;
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while (++index < start) {
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otherArgs[index] = args[index];
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}
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otherArgs[start] = rest;
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return func.apply(this, otherArgs);
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};
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}
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module.exports = restParam;
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