First transform one of the hashes to use all lowercase keys. Then check existence of lc $other_key.

Here's a Perl 6 solution: 

my %lc1 = %hash1.keys>>.lc Z %hash1.values;
for %hash2.keys -> $k {
    say "$k ", %lc1.exists($k) ?? 'Matched' !! 'Did not match';
}

[download]

Transforming the code to Perl 5 shouldn't be too hard.

Perl 6 - second systems done right

In reply to Re: Ignore Case when comparing Hash Keys by moritz
in thread Ignore Case when comparing Hash Keys by avidcoder

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