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var apply = require('./_apply'),
toInteger = require('./toInteger');
/** Used as the `TypeError` message for "Functions" methods. */
var FUNC_ERROR_TEXT = 'Expected a function';
/* Built-in 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://mdn.io/rest_parameters).
*
* @static
* @memberOf _
* @since 4.0.0
* @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 = _.rest(function(what, names) {
* return what + ' ' + _.initial(names).join(', ') +
* (_.size(names) > 1 ? ', & ' : '') + _.last(names);
* });
*
* say('hello', 'fred', 'barney', 'pebbles');
* // => 'hello fred, barney, & pebbles'
*/
function rest(func, start) {
if (typeof func != 'function') {
throw new TypeError(FUNC_ERROR_TEXT);
}
start = nativeMax(start === undefined ? (func.length - 1) : toInteger(start), 0);
return function() {
var args = arguments,
index = -1,
length = nativeMax(args.length - start, 0),
array = Array(length);
while (++index < length) {
array[index] = args[start + index];
}
switch (start) {
case 0: return func.call(this, array);
case 1: return func.call(this, args[0], array);
case 2: return func.call(this, args[0], args[1], array);
}
var otherArgs = Array(start + 1);
index = -1;
while (++index < start) {
otherArgs[index] = args[index];
}
otherArgs[start] = array;
return apply(func, this, otherArgs);
};
}
module.exports = rest;