Hi Monks!

The following code changes contents of array @a: 

use strict;
use Data::Dumper;

my @a = qw(1 2 3);

print Dumper(\@a);
for my $b (@a) {
    $b *= 2;
}
print Dumper(\@a);

[download]
Which is the best (most effective) way to make sure that no code inside the loop will modify array contents? I'm looking for a way to make the list not to be assignable.

--dda

In reply to Preserve array contents in for() loop by dda

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