Personally, I wouldn't use map in either of those places. Definitely not in the second, since it would be evaluating it for side effects only. For the first you could use 
%byFile = map {(split /\s+/)[1,0]} <DATA>;

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with the proviso that it would remove anything already in %byFile. That is, it would take each element from DATA and translate it into two elements, creating a list of pairs to be treated as a hash. But I still don't think this is a great place for map, because it's not as easy to read (and quite a bit more confusing).

In reply to Re: I don't get map. How would I use map here? by Eimi Metamorphoumai
in thread I don't get map. How would I use map here? by Plankton

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