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