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Should `findSingle` has the default predicate?

See original GitHub issue

findSingle in collections module has the default ~~selector~~ predicate of (_) => true. Does this make sense? What’s the use case?

context of this discussion: https://github.com/denoland/deno_std/pull/1166#issuecomment-917268388

Issue Analytics

State:
Created 2 years ago
Comments:10 (10 by maintainers)

Top GitHub Comments

3reactions

timreichencommented, Sep 15, 2021

Just for completeness here the reasons why I find we should remove the default predicate

the name findSingle corresponds to find and findIndex which have a mandatory predicate.
these cases all return the same value with the default predicate which does not give the user a clue, if the array is empty, has a single unique value or not:

findSingle([]) // returns undefined
findSingle([undefined]) // returns undefined
findSingle([undefined, undefined]) // returns undefined

1reaction

timreichencommented, May 23, 2022

@kt3k I think this issue can be closed since the PR got merged.

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