2 var $export = require('./_export')
3 , $fails = require('./_fails')
4 , aNumberValue = require('./_a-number-value')
5 , $toPrecision = 1..toPrecision;
7 $export($export.P + $export.F * ($fails(function(){
9 return $toPrecision.call(1, undefined) !== '1';
10 }) || !$fails(function(){
12 $toPrecision.call({});
14 toPrecision: function toPrecision(precision){
15 var that = aNumberValue(this, 'Number#toPrecision: incorrect invocation!');
16 return precision === undefined ? $toPrecision.call(that) : $toPrecision.call(that, precision);