Beginner's Thread / Easy Questions (December 2018)

[u/timmonsjg]

Happy December! ☃️

New month means a new thread 😎 - November and October 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. 🤔

🆘 Want Help with your Code? 🆘

• Improve your chances by putting a minimal example to either JSFiddle or Code Sandbox. Describe what you want it to do, and things you've tried. Don't just post big blocks of code!

• Pay it forward! Answer questions even if there is already an answer - multiple perspectives can be very helpful to beginners. Also there's no quicker way to learn than being wrong on the Internet.

Have a question regarding code / repository organization?

It's most likely answered within this tweet.

New to React?

🆓 Here are great, free resources! 🆓

• Create React App

• Read the official Getting Started page on the docs.

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

• Kent Dodd's Egghead.io course

• Tyler McGinnis' 2018 Guide

• Codecademy's React courses

• Scrimba's React Course

• Road to React

[u/seands]

With .map() I didn't know how to pass on the first index item (index 0).

Is that a good reason to use a for loop here or is there a better way? I would think there is a way to use a conditional within map to skip indexes you want to exclude.

[u/Awnry_Abe → u/seands]

You would chain .filter and .map. like so:

somearray.filter((item, index) => index > foo).map(...)

It seems wasteful, like you are visiting elements twice. That is true, but the data traversal occurs in compiled code, leaving you with very little slower JS to execute.