javascript - polyfill和transpiler有什么区别？(What is the difference between polyfill and transpiler?)

Question

What is the difference between a polyfill and transpiler?

(polyfill和transpiler有什么区别？)

I often read the same term used in similar context.

(我经常阅读在类似情况下使用的相同术语。)

  ask by Rohit Sharma translate from so

Answer 1

Both approaches serve the same purpose: You can write code, that uses some features, which are not yet implemented in your target environment.

(两种方法具有相同的目的：可以编写使用某些功能的代码，而这些功能尚未在目标环境中实现。)

They do this, however, by using different techniques.

(但是，他们通过使用不同的技术来做到这一点。)

A polyfill will try to emulate certain APIs, so can use them as if they were already implemented.

(polyfill将尝试模拟某些API，因此可以像已实现它们一样使用它们。)

A transpiler on the other hand will transform your code and replace the respective code section by other code, which can already be executed.

(在另一方面，一个transpiler将改变你的代码和其它代码，这已经可以执行替换相应的代码段。)

Typically you use a polyfill, if your target browser did not yet implement the latest bleeding edge feature (read browser APIs) you want to use.

(如果目标浏览器尚未实现您要使用的最新功能（读取浏览器API），则通常使用polyfill。)

A transpiler on the other hand will let you use language features, the target environment does not support yet, eg some ES6 features like fat arrow functions .

(另一方面，编译器将允许您使用语言功能，但目标环境尚不支持，例如某些ES6功能，例如粗箭头功能 。)