When I first learned about map in Perl, I assumed it behaved the same way as map in other languages I was using at the time - Haskell and ML. In these languages, the mapped function takes one argument and returns one value. This is equivalent to Perl's map using scalar context, which it perfectly well could have done. This was (presumably) an intentional design decision on Larry's part. Had it been the other way, we could guarantee that map would always return a list of exactly the same length as its argument list, and issues like the one you describe wouldn't arise. On the other hand, we wouldn't have the flexibility to return longer or shorter lists if appropriate. So it's a tradeoff.

In reply to Re: Unhappy returns by Errto
in thread Unhappy returns by tlm

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