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4 years ago
// Credit:
// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/round
// #Decimal_rounding
"use strict";
var isValue = require("../object/is-value")
, ensureInteger = require("../object/ensure-integer");
var split = String.prototype.split;
module.exports = function (type) {
return function (value/*, exp*/) {
value = Number(value);
var exp = arguments[1];
if (isValue(exp)) exp = ensureInteger(exp);
if (!value) return value;
if (!exp) return Math[type](value);
if (!isFinite(value)) return value;
// Shift
var tokens = split.call(value, "e");
value = Math[type](tokens[0] + "e" + ((tokens[1] || 0) - exp));
// Shift back
tokens = value.toString().split("e");
return Number(tokens[0] + "e" + (Number(tokens[1] || 0) + exp));
};
};