30-seconds-of-code: [FEATURE] castArray for null and undefined => []

[emelendez]

[FEATURE] castArray for null and undefined => []

Category: new feature for "castArray"

Suggestion

instead of:
const castArray = val => (Array.isArray(val) ? val : [val]);
more complete:
const castArray = val => Array.isArray(val) ? val : val == null ? [] : [val];

examples:

castArray('foo'); // ['foo']
castArray([1]); // [1]
castArray(null); // []
castArray(undefined); // []

so includes case of "null" or undefined values which results in an empty array. Also no need of parenthesis in code.
I have to include this because 90% of cases you castArray(theunexpectedresultofthingelse()).map(...) and is useful in resulting data null or undefined from theunexpect...()

[Chalarangelo]

undefined means there is nothing there, essentially forcing us to cast to something. null however is a valid value, so what if you want to create an array of a single element with the value null? I think the behavior should remain as-is, but we could add a method that casts null into undefined and vice versa which could work in combination with this for people that want to have this behavior or something? Probably not a popular opinion. Let's see what others think.

[skatcat31]

Array indexes that contain null or undefined values are perfectly valid in code. Often you want either a lack of data but not pointer(null) or a lack of pointer(undefined) so that you know if something has gone wrong with an intermediate step. I use that sad fact often when I'm using collections that need to be collated or fetched.

Otherwise there would be no need for the === behavior regarding null and undefined. We want those behaviors kept same.

[skatcat31]

I'm closing this issue since we want to preserve comparison code and empty array indexes as expected and due to lack of activity

[lock[bot]]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for any follow-up tasks.