my $x = { map {; $_ + 1 => (qw/Jan Feb Mar/)[$_] } 0 .. 2 }

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Perl 6 solution: 

my $x = hash <Jan Feb Mar ...> Z 1..12;

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You can emulate that in Perl 5 with the zip() function from List::MoreUtils

Perl 6 - links to (nearly) everything that is Perl 6.

In reply to Re: On-the-fly hashref by moritz
in thread On-the-fly hashref by oko1

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