I have a simple rule of thumb when choosing to use array methods, and I'd like to share it with you. The array methods I'm discussing here are:

I took John Lindquist's online video course Build Your Own RxJS Pipeable Operators which comprises 12 videos in 31 minutes total. Yep, that is fast! While I can recommend the course if you're interested in RxJS 6, you do need some experience with RxJS, and Lindquist is super speedy necessitating frequent pauses.

You're using a bundler like Webpack that squeezes those modules into a single minimized javascript file, so you want to keep that line as-is.