in reply to undef a variable for a loop

I don't see why you have any problems. Cleaned up: 

for my $exch (@exch) {
   for my $i (0 .. $#completefile) {
      if (my ($su_adapter, $su_date) = $completefile[$i] =~ /.../) {
         print $su_adapter, $su_date;
      }
   }
}

[download]

Or is the print outside of the if? That wouldn't make any sense.

Replies are listed 'Best First'.
Re^2: undef a variable for a loop
by csiepka (Initiate) on May 15, 2009 at 18:41 UTC
    Actually the print IS outside of the if, and that's only because all I want is the final match for the $exch, etc of each file.
[reply]
      That's what it does already thanks to the leading /.+/. Well, you might have to replace the leading /.+/ with /(?s:.)+/ so that it matches newlines.
[reply]
[d/l]
[select]
      Based on this additional information, you probably mean something like this: 

      foreach $exch(@exch) { 
    undef($su_adapter);
    undef($su_date);
    for($i=0; $i<=$#completefile; $i++) { 
        if($completefile[$i]=~ m/^.+\\(.+)_.+\..+?:(.+?)\s-\s(.+?)\s.+
+?\/$exch\s\|.+::(.*Up)\(\)/) { 
            $su_adapter=$1; 
            $su_date=$2; 
        }
    }
    print $su_adapter, $su_date;
}

      [download]

      Note that there are a bunch of easy modifications (as shown in ikegami's post) that can simplify your code and reduce its predilection for bugs.

[reply]
[d/l]
        No. Four problems with your solution:
        • undef($var); is less efficient than $var = undef;.
        • The print still needs to be in an if in case there was no match.
        • Using undef at all is useless (because of previous point).
        • That doesn't find the last match of each file. It only finds the last match of one file.
[reply]
[d/l]
[select]

In Section Seekers of Perl Wisdom