Regarding the older Perl workaround, Corion's solution can roughly equivalently be expressed as

map { s!.*/!!; $_ } ...
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providing that the array you are feeding is not read only (i.e. @ARGV works but qw|1.2 3.4 5.6| would require the lexical misdirection) and you don't care if it mutates.

I think the more natural way of expressing this, since you are really operating on every element, would be to write

s!.*/!! for @ARGV;
print "Lexicons: ", join(", ", @ARGV[FIRST_LEXICON .. $#ARGV]), "\n";
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The general rule of thumb/best practice-y thing is you should only use maps when you use the return value; and for/foreach when you are operating on each element. The lexical assignment in Corion's solution essentially turns the operation into something mappier.