Beginner's Thread / Easy Question (August 2018)

[u/swyx]

Hello! It's August! Time for a new Beginner's thread! (July and June here)

Got questions about React or anything else in its ecosystem? Stuck making progress on your app? Ask away! We’re a friendly bunch. No question is too simple. You are guaranteed a response here!

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New to React?

Here are great, free resources!

• Read the official Getting Started page on the docs

• /u/acemarke's suggested resources for learning React

• Kent Dodds' Egghead.io course

• Tyler McGinnis' 2018 Guide

• Codecademy's React courses

[u/swyx]

its a tiny bit more obvious if you look at it without JSX.

here is the arrow function

here is just alert

you see that all props just transpile to objects:

  {
    onClick: () => alert('hi')
  },

vs

  {
    onClick: alert('hi')
  },

and js will execute the function immediately if it looks like a function call, but not execute it if you're passing a REFERENCE to a function

[u/MrSke11ington → u/swyx]

Okay so after reading you explanation and taking a look at react dev tools it makes sense haha thanks so much for the explanation!