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| /** | |
| * Repeats the given string `n` times. | |
| * | |
| * @since 3.0.0 | |
| * @category String | |
| * @param {string} [string=''] The string to repeat. | |
| * @param {number} [n=1] The number of times to repeat the string. | |
| * @returns {string} Returns the repeated string. | |
| * @example | |
| * | |
| * repeat('*', 3) | |
| * // => '***' | |
| * | |
| * repeat('abc', 2) | |
| * // => 'abcabc' | |
| * | |
| * repeat('abc', 0) | |
| * // => '' | |
| */ | |
| function repeat(string, n) { | |
| let result = '' | |
| if (!string || n < 1 || n > Number.MAX_SAFE_INTEGER) { | |
| return result | |
| } | |
| // Leverage the exponentiation by squaring algorithm for a faster repeat. | |
| // See https://en.wikipedia.org/wiki/Exponentiation_by_squaring for more details. | |
| do { | |
| if (n % 2) { | |
| result += string | |
| } | |
| n = Math.floor(n / 2) | |
| if (n) { | |
| string += string | |
| } | |
| } while (n) | |
| return result | |
| } | |
| export default repeat |