You may like:

my %hash = map {$_ => undef} @keys;

[download]

or:

my $hashRef = {foo => {map {$_ => undef} @keys}};

[download]

for the nested key hash ref version.

True laziness is hard work

In reply to Re: How to create a hash whose values are undef? by GrandFather
in thread How to create a hash whose values are undef? by Anonymous Monk

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