String#presence is a very useful method for when dealing with String? typed variables to ensure there is a non-blank, non-nil value. However, I sometimes notice myself wanting to something similar, but with an array. That is, perform some logic on an array that is non-nil, and not empty. Of which, h…

The main benefit is when those arrays are mostly empty. Using nil avoids the GC allocation. In the compiler is common, but I am not sure it’s really needed in most application’s code.

String#presence can be handy for handling HTML forms where "" functionally equivalent to nil. Most other usage I see of it would be better served by an actual nil. One of the most confusing things for me when reading code is multiple-negative naming, like case_insensitive: false , so sometimes it ca…

Previous related discussions: Collections: `any?` vs `!empty` - #18 by straight-shoota Introduce `Enumerable#present?` · Issue #13847 · crystal-lang/crystal · GitHub

Add `Array#presence`

Crystal Contrib

straight-shoota January 6, 2025, 10:46am 4

Previous related discussions:

Collections: `any?` vs `!empty` - #18 by straight-shoota
Introduce `Enumerable#present?` · Issue #13847 · crystal-lang/crystal · GitHub

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Add `Array#presence`

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