_.isFunction（a）与==='function'的类型？ JavaScript的 [英] _.isFunction(a) vs. typeof a === 'function'? javascript

问题描述

我认为这可能只是性能问题 - http://jsperf.com/ compare-underscore-js-isfunction-with-typeof-function / 2

I think it might be only performance case - http://jsperf.com/comparing-underscore-js-isfunction-with-typeof-function/2

似乎 typeof 更快..所以我的问题是 - 哪个更适合使用？

And seems that typeof is faster.. so my question is - which is more appropriate to use?

推荐答案

没有理由不使用 typeof 。

不仅速度快，而且ECMAScript规范确保所有函数都具有函数类型，并且只有函数可以具有函数类型：

Not only is it faster but the ECMAScript specification ensures that all functions have a type of "function" and that only functions can have a type of "function" :

此运算符为专门设计用于获取值的类型，为什么不使用它？

This operator was specifically designed to get the type of a value, so why not use it ?

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