Hi everyone
I found a run error in my code and after a very long time,
I've determined which code line is the 1 responsible for adding an element to my array.
The weird thing is that this line only "looks" at the element, not setting it !
Basically it looks like it is being created because it was "looked" at (very "Heisenberg's uncertainty principle" like).
Hereis my code: 
if($cond->{Par} =~ /^K(\d+)/)
{
  my $qqq = scalar(@{$this->{N}});
  $testedNVal = $this->{N}[$1]{Val};   # freak line
  unless($qqq == scalar(@{$this->{N}}))
  {print 'how is this possible ?';<>;}
}

[download]
By substituting for $testedNVal = 0 + $this->{N}[$1]{Val};, I could determine the print only occurs when $this->{N}[$1]{Val} is undef (by 'num + undef' warning).
(The new element is a ref, referring an empty hash)
I figured maybe by setting ("=") it directly to a var, I create a reference to something and force it to exist, but if that's correct than the "= 0 +" shouldn't have done the same thing (but it did).

Can someone please explain whats going on, and how can I solve it ?
(if I even ask if it's exists/defined I'll create it by access so.. ?)

Thoughts ?
Thx

In reply to Can an element be created because it was accessed ? by palkia

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