return $paths only if ...

Hellooo

I have a problem/question.I have this code(just a part ):

 ############  SCAN DIRECTORY SUBROUTRINE ####################
{
    my @paths;
    sub dir_listing {
        my ($root) = @_;
        $root .= '/' unless $root =~ /\/$/;
        for my $f (glob "$root*"){
            push @{$paths}, $f if $f =~ m/\.rar$/;
            dir_listing($f) if -d $f;
        }
        return $paths;
    }
}
[download]

and the problem is that "return" is defined even if directory does not contain any .rar files.

To check if subroutine returned any paths i use:

if (defined $paths){
              ###do something;
              print "paths defined"; }
else{
#do something else;
print "paths not defined"; }
[download]

When i run the script,all i get is "paths defined" even if my directory does not contain rar files.

Help ~! :(

Comment on return $paths only if ... Select or Download Code
Re: return $paths only if ... by toolic (Chancellor) on Aug 20, 2012 at 14:44 UTC
When I use strict, I get this compile error: `Global symbol "$paths" requires explicit package name at` [download] Change: `my @paths;` [download] to: `my $paths;` [download] That may not solve your problem, but it's a step in the right direction.	[reply] [d/l] [select]
Re^2: return $paths only if ... by cesapun (Acolyte) on Aug 20, 2012 at 15:13 UTC
Before `if (defined $paths){` i have `my $paths = [];` so that's not the problem. :(	[reply] [d/l] [select]
Re^3: return $paths only if ... by Athanasius (Vicar) on Aug 20, 2012 at 15:34 UTC
No, toolic wasn’t referring to the `$paths` in your `if (defined $paths){` [download] test, but rather to the two “paths” variables in scope at `sub dir_listing` — `@paths` and `$paths`, which are entirely separate variables (except that they happen to share the same name after the sigil). The first is an array, which is never used; the second is a scalar, which you are treating as an array reference. See the code by Anonymous Monk, below, for the correct way of declaring and using these variables. Athanasius <°(((>< contra mundum	[reply] [d/l]
Re: return $paths only if ... by aitap (Chaplain) on Aug 20, 2012 at 15:18 UTC
Try checking for elements inside the array, not for definedness. For example, `if ($#{$paths} > -1) { ... }`. Sorry if my advice was wrong.	[reply] [d/l]
Re^2: return $paths only if ... by chromatic (Archbishop) on Aug 20, 2012 at 16:33 UTC
`if (@paths)` is simpler. Improve your skills with Modern Perl: the free book.	[reply] [d/l]
Re: return $paths only if ... by Anonymous Monk on Aug 20, 2012 at 15:23 UTC
`use strict; use warnings; ############ SCAN DIRECTORY SUBROUTRINE #################### { my $paths = []; sub dir_listing { my ($root) = @_; $root .= '/' unless $root =~ /\/$/; for my $f (glob "$root*") { push @{$paths}, $f if $f =~ m/\.rar$/; dir_listing($f) if -d $f; } return $paths; } } my $rar_files = dir_listing('/a/path'); if (scalar @{$rar_files}) { ###do something; print "paths defined"; } else { #do something else; print "paths not defined"; }` [download]	[reply] [d/l]
Re^2: return $paths only if ... by cesapun (Acolyte) on Aug 20, 2012 at 17:04 UTC
Many thanks. That's what i was looking for. Close this.:D	[reply]


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