Thanks for pointing out that "delete $array[$idx]" is deprecated, and generates undefs.

Just to illustrate the subtle behaviour that was masked in my previous post, here is a demo of potential disaster the appearance of the undef could cause: 

perl -MData::Dumper -E 'my $r=[map { id=>$_ }, ("b","a".."c","b")]; 
     say Dumper $r;
     my %h;
      $h{$r->[$_]{id}}++ and delete $r->[$_] for  0..$#$r;
    say Dumper $r'
--- SECOND (Relevant) PART of OUTPUT---
$VAR1 = [
          {
            'id' => 'b'
          },
          {
            'id' => 'a'
          },
          undef,
          {
            'id' => 'c'
          }
        ];

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        What is the sound of Perl? Is it not the sound of a wall that people have stopped banging their heads against?
              -Larry Wall, 1992

In reply to Re^3: removing duplicates from an array of hashes by NetWallah
in thread removing duplicates from an array of hashes by Anonymous Monk

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