Records & Tuples, a very interesting proposal, has just reached stage 2 at TC39. They bring deeply immutable data structures to JavaScript.
But don’t overlook their equality properties, that are VERY interesting for React.
A whole category of React bugs are related to unstable object identities:
- Performance: re-renders that could be avoided
- Behavior: useless effect re-executions, infinite loops
- API surface: unability to express when a stable object identity matters
I will explain the basics of Records & Tuples, and how they can solve real world React issues.
Records & Tuples 101
This article is about Records & Tuples <u>for React</u>. I’ll only cover the basics here.
They look like regular Objects and Arrays, with a # prefix.
const record = #{a: 1, b: 2};record.a; …
Sébastien Lorber is a React Native developer, member of the react navigation team. He’s pleased to announce his latest contribution: Instagram-like history-based back behavior for all tab navigators.
Before react navigation 3.2, the only back behaviors available for a tab navigator were:
- none: the back action does not affect the tabs at all
- initialRoute: the back action resets to the config’s initial route
For a long time, it has been requested to add more back behaviors to tab navigators (link1 link2 link3 link4 link5). An official RFC was made to design the feature.
Reply to “Stop Trying to Catch Me”
Original blog: http://jlongster.com/Stop-Trying-to-Catch-Me
So to sum up what you really seems to want is:
- Fail fast on typos
- Easily find the typos
I guess you also mean other kind of programmer errors like calling methods on undefined…
Just some words on Java/Scala
I’m going to talk about what exist in other languages so just to avoid confusion.
Scala runs on the JVM and uses Java libs.
A javascript promise is a bit like a Java or Scala Future.
This can be quite confusing but we have a different terminology for almost exactly the same thing.
Deferred…
Sebastien LORBER
React developer since 2014
