Here is an more declarative alternative to do the tests and assignment you show above: 
  %tags = ( %tags,   
            %{ {l=>\%leftright, r=>\%leftright, t=>\%topbottom,  b=>\%
+topbottom }->{$position} } 
          );

[download]
It will give the right results (with warnings) if any of the expected values is not defined, or incorrect.

        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: Code cleanup; how best to deal with: defined(%hash) is deprecated at... by NetWallah
in thread Code cleanup; how best to deal with: defined(%hash) is deprecated at... by taint

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