If you have to find the key in your hash given a value, then perhaps your hash is the wrong way around.

As long as your values are valid as hash keys, you can easily swap keys and values with

my %reversed = reverse %hash;

[download]

after which you can find the key corresponding to a value in your original hash, as follows:

my $value = 'whatever';
my $key = $reversed{$value};

[download]

In reply to Re: Parse a huge file and match the lines against a hash entry by ig
in thread Parse a huge file and match the lines against a hash entry by snra_perl

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