time-to-botec

Benchmark sampling in different programming languages
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_createRound.js (1193B)

      1 var root = require('./_root'),
      2     toInteger = require('./toInteger'),
      3     toNumber = require('./toNumber'),
      4     toString = require('./toString');
      5 
      6 /* Built-in method references for those with the same name as other `lodash` methods. */
      7 var nativeIsFinite = root.isFinite,
      8     nativeMin = Math.min;
      9 
     10 /**
     11  * Creates a function like `_.round`.
     12  *
     13  * @private
     14  * @param {string} methodName The name of the `Math` method to use when rounding.
     15  * @returns {Function} Returns the new round function.
     16  */
     17 function createRound(methodName) {
     18   var func = Math[methodName];
     19   return function(number, precision) {
     20     number = toNumber(number);
     21     precision = precision == null ? 0 : nativeMin(toInteger(precision), 292);
     22     if (precision && nativeIsFinite(number)) {
     23       // Shift with exponential notation to avoid floating-point issues.
     24       // See [MDN](https://mdn.io/round#Examples) for more details.
     25       var pair = (toString(number) + 'e').split('e'),
     26           value = func(pair[0] + 'e' + (+pair[1] + precision));
     27 
     28       pair = (toString(value) + 'e').split('e');
     29       return +(pair[0] + 'e' + (+pair[1] - precision));
     30     }
     31     return func(number);
     32   };
     33 }
     34 
     35 module.exports = createRound;