In diagnosing some error problems, I made up a TIE module for printing. It works quite well, but does "wierd things" in one instance. The routine that is called says:

Use of uninitialized value in split at <routine/line> during global destruction.

The code is pretty simple (reconstructed a bit): 

sub fool
  {
  my @vals;
  my $n;
  my $i;
  while (@_)
    {
    @vals = split /(\n)/, (shift); # Error happens here
    $n = @vals;    
    for ($i = 0; $i < $n; $i++)
      {
      print "The value is: $vals[$i] \n"; # Or similar action
      }
    }
  }

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My question: how do I detect that this error is GOING to happen with the called arguments (in this case to the 'fool' routine) so I can print out a more intelligent error message?

Is there any way I can "produce" this same error message using the 'fool' routine as shown above. It would "enlighten" me quite a bit.

In reply to Wierd error message by herby1620

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