Help on foreach loop

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Hello everyone, I have taken a shot at a perl script below, can anyone help me out and tell me why my $newFile variable is not getting reset, can someone help me on this

foreach $arrFileList(@arrFileList)
 {
   print "I am doing this file $arrFileList\n";
   open (FILE, "$sourceDir/$arrFileList") or die "could not open $sour
+ceDir/$arrFileList: $!\n";
   @Lines = <FILE>;
   close FILE;
   $origField = (split /\|/, $Lines[3])[-3];
   $commonField = (split /\|/, $Lines[13])[-1];
   $commonField = "NX2|01|$commonField";
   chomp $commonField;
   print "my commonField is this $commonField\n";

   @ARGV = <$responseDir/*>;
   while (<>)
    {
         $newFile = $ARGV, last if /^"$commonField"$/;
    }
   print "my newFile to change is $newFile\n";
   if (defined($newFile))
    {
      system ("perl -pi -e 's/$replaceField/$origField/g' $newFile");
      print "Done doing perl s/$replaceField/$origField/g $newFile\n";
      system ("mv $newFile $responseDone");
      print "Done moving $newFile to $responseDone\n";
      system ("mv $sourceDir/$arrFileList $processed");
      print "Done moving $sourceDir/$arrFileList to $processed\n";
    }
 }
[download]

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Re: Help on foreach loop by Roy Johnson (Monsignor) on Sep 09, 2004 at 15:15 UTC
It would seem that your regex isn't matching on subsequent passes. Since you never reset it, it won't be undef, it will be whatever it used to be. `@ARGV = <$responseDir/>; undef $newFile; # Force reset while (<>) { $newFile = $ARGV, print(STDERR "Found $commonField\n"), last +if /^"$commonField"$/; } print "my newFile to change is $newFile\n";` [download] Caution:* Contents may have been coded under pressure.	[reply] [d/l]
Re^2: Help on foreach loop by Anonymous Monk on Sep 09, 2004 at 15:32 UTC
it still dosen't reset $newFile, for the first iteration $newFile = sample.txt in the next iteration $newFile is still sample.txt, and in my script I clearly move the sample.txt to another diretory after it was found the first time,	[reply]
Re^3: Help on foreach loop by Roy Johnson (Monsignor) on Sep 09, 2004 at 15:53 UTC
Sounds like $ARGV isn't changing, possibly because the file isn't closed? Try closing ARGV within the while loop: `@ARGV = <$responseDir/>; while (<>) { $newFile = $ARGV, close ARGV, last if /^"$commonField"$/; }` [download] Caution:* Contents may have been coded under pressure.	[reply] [d/l]
Re: Help on foreach loop by Random_Walk (Prior) on Sep 09, 2004 at 15:01 UTC
Your code.. `@ARGV = <$responseDir/>; while (<>) { $newFile = $ARGV, last if /^"$commonField"$/; }` [download] Is going through each file in $responseDir opening it and reading each line. when you get a line which matches common field you will edit that file then go on to the next element of @arrFileList. Perhaps you wanted something more like # replace from @ARGV = <$responseDir/>; foreach $file (<$responseDir/*>) { open FH, "$responseDir/$file" or die "$!\n"; my ($edit, @temp); while (<FH>) { push @temp, $_; $edit++ if /^"$commonField"$/; } close FH; next unless $edit; open NEW, ">$responseDone/$file" or die "$!\n"; foreach (@temp) { s/$replaceField/$origField/g; print NEW; } close NEW; print "Done s/$replaceField/$origField/g $file\n"; unlink "$responseDir/$file"; print "removed original\n"; system ("mv $sourceDir/$arrFileList $processed"); print "moved $sourceDir/$arrFileList to $processed\n"; } [download] Cheers, R.	[reply] [d/l] [select]
Re: Help on foreach loop by ysth (Canon) on Sep 09, 2004 at 15:48 UTC
I think @ARGV is only reaccessed by <> when the ARGV file is at eof/closed. Try: `$newfile = $ARGV, close(ARGV), last if /^"$commonField"$/;`	[reply] [d/l]
Re^2: Help on foreach loop by Anonymous Monk on Sep 09, 2004 at 16:01 UTC
nope .. didn't work	[reply]
Re^3: Help on foreach loop by ysth (Canon) on Sep 09, 2004 at 16:05 UTC
I think it's still needed, even if it doesn't fix your apparent problem. Have you printed out @ARGV before and after the while loop to see if it is as you expect? I suggest lots of print statements or a run through with perl -d.	[reply]
Re^4: Help on foreach loop by Anonymous Monk on Sep 09, 2004 at 17:24 UTC
Re^5: Help on foreach loop by Not_a_Number (Prior) on Sep 09, 2004 at 17:45 UTC
Some notes below your chosen depth have not been shown here
Re: Help on foreach loop by Prior Nacre V (Hermit) on Sep 09, 2004 at 14:46 UTC
... why my $newFile variable ... It actually does need to be: `my $newFile ...` [download] Also, your while block should include the print and if block. Regards, PN5	[reply] [d/l]
Re^2: Help on foreach loop by Anonymous Monk on Sep 09, 2004 at 14:55 UTC
didn't work, maybe my syntax might be wrong, is it possible for you to post the changes thanks	[reply]
Re: Help on foreach loop by jockel (Beadle) on Sep 09, 2004 at 15:05 UTC
Hi vroom Hmm.. There are many strange things in your script (atleast strange for me) `@ARGV = <$responseDir/>; while (<>) { $newFile = $ARGV, last if /^"$commonField"$/; }` [download] Does the `@ARGV = <$responseDir/>;` acctually work? Why `while (<>)` when u check against that but assigning from $ARGV (which hasn't anything to do with @ARGV) well that was just a few questions ... Good luck /jocke	[reply] [d/l] [select]
Re^2: Help on foreach loop by Anonymous Monk on Sep 09, 2004 at 15:07 UTC
yes that did work, the problem comes when it iterates through the next foreach loop, it dosen't change the value of $newFile	[reply]
Re^2: Help on foreach loop by Mr. Muskrat (Canon) on Sep 09, 2004 at 23:57 UTC
Hi vroom Since when does 'vroom' eq 'Anonymous Monk'? :)	[reply]
Re^3: Help on foreach loop by Your Mother (Archbishop) on Sep 10, 2004 at 05:27 UTC
The preview page shows "by vroom" (as the edit node, I'm sure) so that might be it.	[reply]