When you write the following:

$my_hash{"T::c"}

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Perl interprets the hash key as the string T::c. The quotes are only there so that Perl knows that you mean the string T::c and not something that Perl could interpret as something else (like a package name, in this case).

Constructing a value that contains quotes will not make the lookup successful because the hash key as interpreted by Perl does not contain quotes.

To look at what Perl sees in a hash, consider using Data::Dumper:

use Data::Dumper;

my %my_hash = (
    '"with_quotes_in_key"'  => 'a value',
    "without_quotes_in_key" => 'another value',
    bare_key                => 'a third value',
    "T::c"                  => 'your value',
    '"Another::thing"'      => 'a fifth value',
);

print Dumper \%my_hash;

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In reply to Re^3: hash key by Corion
in thread hash key by aviw

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