How to validate array length

[BigDog1400]

Hi. I am trying to understand how to make a case for 1) array.length is greater than > 0 2) array.length is 0.

This works fine. But i don't want to nest another match. I will like to something like this, but i think that it cause another permutations to exist and it throw some errors

I also try with the P.array but i don't fully understand the release notes 😅 .

so... does someone knows the best way to validate array length?

[gvergnaud]

Hey!
The best way to match a specific array length is to use a (variadic) tuple pattern:

match(array)
  .with(
    { status: 'success', data: [] }
    () => "matches empty arrays"
  )
  .with(
    { status: 'success', data: [P.any] }
    () => "matches arrays with exactly 1 element"
  )
  .with(
    { status: 'success', data: [P.any, P.any] }
    () => "matches arrays with exactly 2 elements"
  )
  .with(
    { status: 'success', data: [P.any, ...P.array()] }
    () => "matches arrays with at least 1 element"
  )