If you wanted to let scoping clear the variable for you, you can do it like this:

1:  for $i (1..10) {
2:      my $tempstring;
3:      for $j (1..10) {
4:          $tempstring .= $array[$j];
5:      }
6:      $final[$i] = $tempstring;
7:  }

[download]

What that does, is that $tempstring is declared in the outter for block. Each time you iterate through the outter for block, $tempstring falls out of scope at the end of the block, and is re-introduced in the next iteration. Quite literally, even on the last iteration of the outter for block, once you leave the block behind, $tempstring is gone. I prefer this method because it ensures that temporary, or loop variables just disappear when I don't need them anymore.

For that matter, if you no longer are going to be needing access to $i and $j, you can declare them with block scope as well: 

for my $i (1..10) {.......

[download]

This will ensure that at the end of the looping those variables also disappear, rather than possibly clouding up some other portion of your code. This is the merit of scoping; limiting scope! That's a good thing. IMHO, variables should only exist within the relm of where they are needed.

Dave

"If I had my life to do over again, I'd be a plumber." -- Albert Einstein

In reply to Re: Re: Re: declaration of variables by davido
in thread declaration of variables by Murcia

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