I want to initialize a hash so that the keys are taken from an array, and each value is 0. I hoped this would work:
my @keynames = (qw/first second third fourth/);

my %hash = map ($_, 0), @keynames;

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But for some reason, %hash is then totally empty. I tried using {leftsquarebracket}$_, 0{rightsquarebracket} instead of ($_, 0), but that only gives me an array of references (erk, I dunno how to escape square brackets :). How can I do this?

As a bonus academic question, what's the best way to do the same thing, but using another array for the initialization values (i.e. not 0)?

In reply to Using map to interlace an array by athomason

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