jeena/en.javascript.info
1
0
Fork 0
Code Issues Pull requests Projects Packages Wiki Activity Actions

Fix possible typos in 1.3.6 (Polyfills and transpilers)

Browse source
This commit is contained in:
Vse Mozhe Buty 2020-12-06 16:26:39 +02:00 • committed by GitHub
parent 433ef6d333
commit eb81e529be
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
1 changed files with 3 additions and 3 deletions
Download patch file Download diff file Expand all files Collapse all files

6
1-js/03-code-quality/06-polyfills/article.md
View file

@ -24,16 +24,16 @@ Here, in this chapter, our purpose is to get the gist of how they work, and thei
A [transpiler](https://en.wikipedia.org/wiki/Source-to-source_compiler) is a special piece of software that can parse ("read and understand") modern code, and rewrite it using older syntax constructs, so that the result would be the same.
E.g. JavaScript before year 2020 didn't have the "nullish coalescing operator" `??`. So, if the visitor uses an outdated browser, it may fail understand the code like `height = height ?? 100`.
E.g. JavaScript before year 2020 didn't have the "nullish coalescing operator" `??`. So, if the visitor uses an outdated browser, it may fail to understand the code like `height = height ?? 100`.
A transpiler would analyze our code and rewrite `height ?? 100` as `(height !== undefined && height !== null) ? height: 100`.
A transpiler would analyze our code and rewrite `height ?? 100` as `(height !== undefined && height !== null) ? height : 100`.
```js
// before running the transpiler
height = height ?? 100;
// after running the transpiler
height = (height !== undefined && height != null) ? height : 100;
height = (height !== undefined && height !== null) ? height : 100;
```
Now the rewritten code is suitable for older JavaScript engines.