I like a modification of your middle suggestion best: 

my %y = map { "prefix_".$_ => 1 } qw(a b c);

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There's no need to put $_ inside quotes, only to have Perl do variable interpolation on that string. :)

Alex / talexb / Toronto

"Groklaw is the open-source mentality applied to legal research" ~ Linus Torvalds

In reply to Re^3: map problem by talexb
in thread map problem by morgon

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