Hasty Treat - Seven Interesting JavaScript Proposals - Async Do, JSON Modules, Immutable Array Methods, and More!


In this Hasty Treat, Scott and Wes talk about seven new JavaScript proposals — what they do, where they’re at, and how you might use them.

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Show Notes

03:32 - Seven new JavaScript proposals

06:25 - JSON Modules

09:55 - Array Find From Last

11:40 - Async Do

  • https://github.com/tc39/proposal-async-do-expressions
  • Async do will allow you to group together a block of code and mark it as async.
  • No need for an iife
  • Downside to this is that it’s a code block, so if you need to return any values, you’ll need to jump that up a scope level.
Promise.all([ async do { let result = await fetch('thing A'); await result.json(); }, async do { let result = await fetch('thing B'); await result.json(); }, ]).then(([a, b]) => console.log([a, b]));

14:33 - Change Array By Copy

17:48 - Temporal

18:35 - As Patterns

20:47 - Pattern Matching

{props => match (props) { when ({ loading }) { ; } when ({ error }) { ; } when ({ data }) { ; } }} Tweet us your tasty treats!

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