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

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;
    }
}

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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 ~! :(

Replies are listed 'Best First'.
Re: return $paths only if ...
by toolic (Bishop) on Aug 20, 2012 at 14:44 UTC
    When I use strict, I get this compile error: 
    Global symbol "$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]
    A reply falls below the community's threshold of quality. You may see it by logging in.
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]
      Many thanks.

      That's what i was looking for.

      Close this.:D
[reply]
Re: return $paths only if ...
by aitap (Curate) on Aug 20, 2012 at 15:18 UTC
    Try checking for elements inside the array, not for definedness. For example, if ($#{$paths} > -1) { ... }.
    Sorry if my advice was wrong.
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[d/l]
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