While folloing perl hack book's example(chap 1 hack 5; it's about auto completion in vim and putting all modules in one file to search from), I found it very surprising that it wasn't working on my linux box
I am sure it was working somewhere else and I overlooked something, I digged in and see if I could make it work on my box

Finally results being at the bottom, and looking at the file that I created after running the script looks like it's working
Can some more experienced monks fix it so that I can see what I should have done instead of what I did?
My maine question is, when encountered below 
            ## Need to get rid of directories, such as 5.8.8 or i386-l
+inux-thread-multi
            ## 5.8.8::URI.pm
            ## i386-linux-thread-multi::Net::DNS::RR::MG.pm
            $file =~ s{^ +\d+\.\d+\.\d+::}{}g;
            $file =~ s{^ ?[^A-Z]+::}{}g;
            $file =~ s/^ +//g;

[download]
Looks like I could have gotten rid of directories more simpler way then applying 3 regex back to back to back?
use File::Find 'find';

# Where to create this list...
my $LIST_DIR  = "$ENV{HOME}/.vim_extras/"
my $LIST_FILE = "file_that_lists_every_installed_Perl_module";

# Make sure the directory is available...
unless (-e $LIST_DIR )
{
    mkdir $LIST_DIR
        or die "Couldn't create directory $LIST_DIR ($!)\\n";
}

# (Re)create the file...
open my $fh, '>', "$LIST_DIR$LIST_FILE"
    or die "Couldn't create file '$LIST_FILE' ($!)\\n";

# Only report each module once (the first time it's seen)...
my %already_seen;

# Walk through the module include directories, finding .pm files...
for my $incl_dir (@INC)
{
    find
    {
        wanted => sub
        {
            my $file = $_;

            # They have to end in .pm...
            return unless $file =~ /\\.pm\\z/;

            # Convert the path name to a module name...
            $file =~ s{^\\Q$incl_dir/\\E}{ };
            $file =~ s{/}{::}g;
            $file =~ s{\\.pm\\z}{ };

            # Handle standard subdirectories (like site_perl/ or 5.8.6
+/)...
            $file =~ s{^.*\\b[a-z_0-9]+::}{ };
            $file =~ s{^\\d+\\.\\d+\\.\\d+::(?:[a-z_][a-z_0-9]*::)?}{ 
+};
            return if $file =~ m{^::};

            # Print the module's name (once)...
            print {$fh} $file, "\\n" unless $already_seen{$file}++;
        },
        no_chdir => 1,
    }, $incl_dir;
}

[download]
so I changed to below and works but how I did it looks very inefficient.. 
for my $incl_dir (@INC)
{
    find
    {
        wanted => sub
        {
            my $file = $_;

            # They have to end in .pm...
            return unless $file =~ /.+\.pm/;
            # Convert the path name to a module name...
            $file =~ s{^\Q$incl_dir/\E}{ };
            $file =~ s{/}{::}g;

            # Handle standard subdirectories (like site_perl/ or 5.8.6
+/)...
            ## 5.8.8::URI.pm
            ## i386-linux-thread-multi::Net::DNS::RR::MG.pm
            $file =~ s{^ +\d+\.\d+\.\d+::}{}g;
            $file =~ s{^ ?[^A-Z]+::}{}g;
            $file =~ s/^ +//g;
            return if $file =~ m{^::};

            # Print the module's name (once)...
            #print "printing\n";
            print {$fh} $file, "\n" unless $already_seen{$file}++;
        },
        no_chdir => 1,
    }, $incl_dir;

[download]

In reply to while following perl hack book by convenientstore

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