How to Prevent Array From Creating Holes

Sparse arrays break loops and counts.

#javascript #sparsearrays #length #bug #howto #arrays

https://www.youtube.com/watch?v=bX_XF_v19bw

Array(3) vs [,,,] Are NOT The Same!

Creating arrays in JavaScript has a hidden trap! Array(3) and [,,,] look identical but behave completely differently. Mind blown!

#javascript #javascripttricks #codingtips #programmingtutorial #arrayconstructor #javascriptquiz #codingchallenge #javascriptshorts #javascriptbugs #sparsearrays #javascriptwtf #arraycreation

https://www.youtube.com/watch?v=Rm7V87ukelA

Array Holes Are NOT undefined?!

MIND BLOWN! An empty slot in an array is NOT the same as undefined. The hole doesn't exist as a property! map() SKIPS holes but processes undefined. This invisible difference will break your code!

#javascript #javascripttricks #arrayholes #sparsearrays #undefined #javascriptweird #javascriptquiz #codingchallenge #javascriptshorts #javascriptwtf #arraymethods #advancedjavascript

https://www.youtube.com/watch?v=gJiOuy3o34U

Array.from() With Sparse Arrays?!

Array.from() has hidden behavior with sparse arrays! Creating arrays this way creates something unexpected. Watch this!

#javascript #javascripttricks #codingtips #programmingtutorial #array.from #javascriptquiz #codingchallenge #javascriptshorts #javascriptbugs #sparsearrays #javascriptwtf #arrayconversion

https://www.youtube.com/watch?v=UQGGJuRt5FU