Accessing list of package names in a module

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

Greetings, I'm looking for a clean way (ie, without using a shell call, grepping, etc) to obtain the list of package names in a module from a calling script. For example, given the following module (Util/Stuff.pm):

package Util::Stuff;
use strict;
use warnings;

package Util::Stuff::aaa1;
sub flag { 1 }
...

package Util::Stuff::aaa2;
sub flag { 0 }
...

package Util::Stuff::aaa3;
sub flag { 1 }
...
...
1;
[download]

I now want to obtain the list programmatically:

Util::Stuff:aaa1
Util::Stuff:aaa2
Util::Stuff:aaa3
[download]

Once I have that info in a list, I want to get the flag values: The manual/existing way:

use Util::Stuff;

my $temp1 = Util::Stuff::aaa1->flag;
my $temp2 = Util::Stuff::aaa2->flag;
my $temp3 = Util::Stuff::aaa3->flag;
[download]

The way I'd like:

use Util::Stuff;

my @names = **get_package_names(Util::Stuff)**
foreach my $name (@names) {
    push @temp, $name->flag;'
}
[download]

Any pointers would be appreciated.

Regards
Henry

Comment on Accessing list of package names in a module Select or Download Code

Replies are listed 'Best First'.
Re: Accessing list of package names in a module by LanX (Saint) on Nov 20, 2008 at 10:03 UTC
Just one remark for better understanding: Each imported package is listed in the ~~namespace~~ symbol table of the importing package. so by scanning the namespaces starting from the root "main" you should find the desired infos. Packages are keys ending with a "::". `use Data::Dumper; print Dumper \%:: ;` [download] you will see entries like `'Data::' => {'::Data::'},` so recursively you can get all the infos you want. Cheers LanX UPDATE: Note: %:: is a abbreviation for %main:: "%packagename*::" is known as "stash" = symbol table hash	[reply] [d/l]
Re^2: Accessing list of package names in a module by FreakyGreenLeaky (Sexton) on Nov 20, 2008 at 10:43 UTC
Aah, that's the one. Nice and simple and takes advantage of goodies hidden internally . Thank you!	[reply]
Re^3: Accessing list of package names in a module by moritz (Cardinal) on Nov 20, 2008 at 16:17 UTC
Symbol tables are hardly "goodies hidden internally", they are documented in perlmod. Though if you come from other programming languages it's not obvious that something like that even exists :-)	[reply]
Re: Accessing list of package names in a module by Anonymous Monk on Nov 20, 2008 at 09:31 UTC
`my $source = do { local(ARGV, $/); @ARGV = $INC{'Util/Stuff.pm'}; <>; }; my @packages = $source =~ m/package\s+[_a-zA-Z][^\S;];/g;` [download] I would use Module::Info `my $mod = Module::Info->new_from_module('Some::Module'); my @packages = $mod->packages_inside;` [download]	[reply] [d/l] [select]
Re^2: Accessing list of package names in a module by FreakyGreenLeaky (Sexton) on Nov 20, 2008 at 10:22 UTC
Thanks, Module::Info looked ideal, but it doesn't correctly return all the package names from a module (it only returns the last for some reason). I'll give the first sample a try now.	[reply]
Re^3: Accessing list of package names in a module by Anonymous Monk on Nov 21, 2008 at 03:24 UTC
You should report that bug.	[reply]
Re^4: Accessing list of package names in a module by Anonymous Monk on Nov 21, 2008 at 03:42 UTC
Re: Accessing list of package names in a module by sathiya.sw (Monk) on Nov 20, 2008 at 14:38 UTC
Simple, go for Devel::Symdump which dumps your symbol table. For your first requirement, use packages method in that. I think simple, and straight way Is It ?	[reply]
Re: Accessing list of package names in a module by Crian (Curate) on Nov 20, 2008 at 10:46 UTC
If you want to analyse foreign modules, you should think of the possibility of functions created by autoload. I don't know how to fetch them too.	[reply]
Re^2: Accessing list of package names in a module by chromatic (Archbishop) on Nov 20, 2008 at 18:47 UTC
If `AUTOLOAD` stores them in the symbol table, they'll be in the symbol table. If `AUTOLOAD` doesn't (and you didn't predeclare them), you won't.	[reply] [d/l] [select]