Re^2: Two arrays into hash

in reply to Re: Two arrays into hash
in thread Two arrays into hash

[@array] can be/usually is written as \@array

Careful. The two are not the same. \@array returns a reference to the existing array. [@array] creates a new (anonymous) copy of the original array and returns a reference to the copy. It's a subtle difference, but an important one.

#!/usr/bin/perl

use strict;
use warnings;

my @arr = (1 .. 5);

my %hash = (
            aref => \@arr,
            copy => [ @arr ],
           );

print "@{$hash{copy}}\n";
print "@{$hash{aref}}\n";

@arr = ('a' .. 'e');

print "@{$hash{copy}}\n"; # original values
print "@{$hash{aref}}\n"; # changed values
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Re^3: Two arrays into hash by Bloodnok (Vicar) on Jul 16, 2009 at 10:43 UTC
Good point, well made - I rather overlooked that didn't I ? Thanx davorg. A user level that continues to overstate my experience :-))	[reply]

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