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Es6 and typescript fixes all this.
by woah 10y ago
Es6 and typescript fixes all this.
- jomamaxx 10y ago"Es6 and typescript fixes all this." ES6 doesn't fix any of it, typescript fixes some of it.
- Arnavion 10y agoES6 adds isNaN and isFinite static methods to Number that don't convert their argument to a number first, so Klathmon's version works. But I don't make any claim about whether it's correct or not. https://babeljs.io/repl/#?babili=false&evaluate=true&lineWrap=false&presets=es2015%2Creact%2Cstage-2&code=function%20isNumber(arg)%20%7B%0A%20%20return%20!Number.isNaN(arg)%20%26%26%20Number.isFinite(arg)%3B%0A%7D%0A%0Aconsole.log(isNumber(100))%3B%0Aconsole.log(isNumber('100'))%3B%0Aconsole.log(isNumber(undefined))%3B%0Aconsole.log(isNumber(null))%3B%0A https://babeljs.io/repl/#?babili=false&evaluate=true&lineWra... Compare step 1 of http://www.ecma-international.org/ecma-262/6.0/#sec-isnan-number http://www.ecma-international.org/ecma-262/6.0/#sec-isnan-nu... with http://www.ecma-international.org/ecma-262/6.0/#sec-number.isnan http://www.ecma-international.org/ecma-262/6.0/#sec-number.i...