Your first mistake was using map as a function and not a keyword. You should have written 
for my $arr ( @results ) {
  ...
  my @row = map { val( $_ ) } @$arr;
  ...
}

[download]
The bug is still there, but it's clearer now that you're working in list context. At that point, you can fix it either by returning an explicit undef from val() (the bad way) or modifying your map body to be val( $_ ) || undef (the good way).
My criteria for good software:
  1. Does it work?
  2. Can someone else come in, make a change, and be reasonably certain no bugs were introduced?

In reply to Re: Unhappy returns by dragonchild
in thread Unhappy returns by tlm

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