time-to-botec

Benchmark sampling in different programming languages
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_baseRepeat.js (952B)

      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 module.exports = baseRepeat;