Personally I would use a grep before or after the map, but when you want to return a varying number of elements from map you can use the ternary operator:

my @b = map {
    s/x//; # this could be written more efficient as tr[x][]d;
    $_ ? $_ : ()
} @a;

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In reply to Re: Basic list manipulation, and a bit of map() confusion... by Corion
in thread Basic list manipulation, and a bit of map() confusion... by cmv

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