1/** Used as references for various `Number` constants. */ 2var MAX_SAFE_INTEGER = 9007199254740991; 3 4/* Built-in method references for those with the same name as other `lodash` methods. */ 5var 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 */ 15function 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 35module.exports = baseRepeat; 36