| // Thanks: https://github.com/monolithed/ECMAScript-6 | |
| 'use strict'; | |
| var exp = Math.exp; | |
| module.exports = function (x) { | |
| if (isNaN(x)) return NaN; | |
| x = Number(x); | |
| if (x === 0) return x; | |
| if (x === Infinity) return Infinity; | |
| if (x === -Infinity) return -1; | |
| if ((x > -1.0e-6) && (x < 1.0e-6)) return x + x * x / 2; | |
| return exp(x) - 1; | |
| }; |