(I came to the conclusion Guido was right about whitespace)

using global... I mean, local our variables. Just like $a and $b. 
use strict;
use warnings;

sub sort_aux {
    our $self;
    $a <=> $b;
}

sub hash_ref_keys_by_value {
    local our $self = shift;
    my @keys = sort by_value
      keys %{ $self->{hash_ref} };
}

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In reply to Re: How can I access object data in a user defined sort cmp function? by Anonymous Monk
in thread How can I access object data in a user defined sort cmp function? by tkguifan

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