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Re^4: non-scalar hash key

by McDarren (Abbot)
on Jun 17, 2009 at 10:09 UTC ( [id://772317]=note: print w/replies, xml ) Need Help??


in reply to Re^3: non-scalar hash key
in thread non-scalar hash key

ah, okay.

Well, a reference to an array is a scalar. So, perhaps something like:

my @foo = qw/1 2 3 4 5 6/; my %bar = ( \@foo => 'elephants', ); my $zonk = \@foo; print "$bar{$zonk}\n";
prints:
elephants

Cheers,
Darren :)

Replies are listed 'Best First'.
Re^5: non-scalar hash key
by citromatik (Curate) on Jun 17, 2009 at 10:33 UTC

    The problem with your suggestion is that two arrays with the same elements will give two entries in the hash (because they will have different references). Consider:

    use strict; use warnings; use Data::Dumper; my @foo = qw/1 2 3 4 5 6/; my @fu = qw/1 2 3 4 5 6/; my %bar = ( \@foo => 'elephants', \@fu => 'zebras' ); print Dumper \%bar;

    Outputs something like:

    $VAR1 = { 'ARRAY(0x18ae770)' => 'zebras', 'ARRAY(0x17f0ec8)' => 'elephants' };

    And:

    my @foo = qw/1 2 3 4 5 6/; my @fu = qw/1 2 3 4 5 6/; my %bar = ( join ('',@foo) => 'elephants', join ('',@fu) => 'zebras' ); print Dumper \%bar;

    Outputs:

    $VAR1 = { '123456' => 'zebras' };

    citromatik

Re^5: non-scalar hash key
by kdejonghe (Novice) on Jun 17, 2009 at 10:13 UTC
    A reference to another array with the same sequence of integers should point to the same hash entry.

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