The special variable, "$_" is used both by grep, and by foreach. Write your loop like this: 

foreach my $dir_try ( @copyOfContentsOfDirectory ) {
    push @pdfNoMatchingDirectory, grep { $_ ne $dir_try } @contentsOfD
+ataBase;
}

[download]

The 'it' variable ($_) from your foreach loop is being masked by the it variable from the grep. This avoids that situation. Also, on each loop iteration, @pdfNoMatchingDirectory is being reset with a new list from grep. I added push so that @pdfNoMatchingDirectory instead accumulates all the elements you're looking for. That may not be what you're after, so you might remove the push again.

You know, I keep seeing the word DataBase in your variables. It would probably be more efficient to use your SQL database's SQL engine to perform the set-symmetric-difference task.


Dave

In reply to Re^4: Question of scope and syntax by davido
in thread Question of scope and syntax by Hellhound4

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