Because you copied the referenced array's contents to a local copy and then modfied the local copy. You never copied it back. Try 

use warnings;
use strict;

my @a = ("a", "b", "c");
Foo(\@a);
print "$_ " foreach(@a);

sub Foo
{
  my $refA = shift;
#  my @b = @$refA;
  $refA->[0] = "hello";
  $refA->[1] = "world";
  $refA->[2] = "Perl";
}

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In reply to Re: Changing items of an array in a function by Anonymous Monk
in thread Changing items of an array in a function by abhishes

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