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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;
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