--- /dev/null
+// 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;
+};