_createRound.js
df143e4977c6master

_createRound.js
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			var root = require('./_root'),
			toInteger = require('./toInteger'),
			toNumber = require('./toNumber'),
			toString = require('./toString');

			/* Built-in method references for those with the same name as other `lodash` methods. */
			var nativeIsFinite = root.isFinite,
			nativeMin = Math.min;

			/**
			* Creates a function like `_.round`.
			*
			* @private
			* @param {string} methodName The name of the `Math` method to use when rounding.
			* @returns {Function} Returns the new round function.
			*/
			function createRound(methodName) {
			var func = Math[methodName];
			return function(number, precision) {
			number = toNumber(number);
			precision = precision == null ? 0 : nativeMin(toInteger(precision), 292);
			if (precision && nativeIsFinite(number)) {
			// Shift with exponential notation to avoid floating-point issues.
			// See [MDN](https://mdn.io/round#Examples) for more details.
			var pair = (toString(number) + 'e').split('e'),
			value = func(pair[0] + 'e' + (+pair[1] + precision));

			pair = (toString(value) + 'e').split('e');
			return +(pair[0] + 'e' + (+pair[1] - precision));
			}
			return func(number);
			};
			}

			module.exports = createRound;