1 | /** Used as references for various `Number` constants. */
|
2 | var MAX_SAFE_INTEGER = 9007199254740991;
|
3 |
|
4 | /* Built-in method references for those with the same name as other `lodash` methods. */
|
5 | var nativeFloor = Math.floor;
|
6 |
|
7 | /**
|
8 | * The base implementation of `_.repeat` which doesn't coerce arguments.
|
9 | *
|
10 | * @private
|
11 | * @param {string} string The string to repeat.
|
12 | * @param {number} n The number of times to repeat the string.
|
13 | * @returns {string} Returns the repeated string.
|
14 | */
|
15 | function baseRepeat(string, n) {
|
16 | var result = '';
|
17 | if (!string || n < 1 || n > MAX_SAFE_INTEGER) {
|
18 | return result;
|
19 | }
|
20 | // Leverage the exponentiation by squaring algorithm for a faster repeat.
|
21 | // See https://en.wikipedia.org/wiki/Exponentiation_by_squaring for more details.
|
22 | do {
|
23 | if (n % 2) {
|
24 | result += string;
|
25 | }
|
26 | n = nativeFloor(n / 2);
|
27 | if (n) {
|
28 | string += string;
|
29 | }
|
30 | } while (n);
|
31 |
|
32 | return result;
|
33 | }
|
34 |
|
35 | export default baseRepeat;
|