1
|
var toInteger = require('./toInteger');
|
2
|
|
3
|
/** Error message constants. */
|
4
|
var FUNC_ERROR_TEXT = 'Expected a function';
|
5
|
|
6
|
/**
|
7
|
* Creates a function that invokes `func`, with the `this` binding and arguments
|
8
|
* of the created function, while it's called less than `n` times. Subsequent
|
9
|
* calls to the created function return the result of the last `func` invocation.
|
10
|
*
|
11
|
* @static
|
12
|
* @memberOf _
|
13
|
* @since 3.0.0
|
14
|
* @category Function
|
15
|
* @param {number} n The number of calls at which `func` is no longer invoked.
|
16
|
* @param {Function} func The function to restrict.
|
17
|
* @returns {Function} Returns the new restricted function.
|
18
|
* @example
|
19
|
*
|
20
|
* jQuery(element).on('click', _.before(5, addContactToList));
|
21
|
* // => Allows adding up to 4 contacts to the list.
|
22
|
*/
|
23
|
function before(n, func) {
|
24
|
var result;
|
25
|
if (typeof func != 'function') {
|
26
|
throw new TypeError(FUNC_ERROR_TEXT);
|
27
|
}
|
28
|
n = toInteger(n);
|
29
|
return function() {
|
30
|
if (--n > 0) {
|
31
|
result = func.apply(this, arguments);
|
32
|
}
|
33
|
if (n <= 1) {
|
34
|
func = undefined;
|
35
|
}
|
36
|
return result;
|
37
|
};
|
38
|
}
|
39
|
|
40
|
module.exports = before;
|