ExtUtils::Depends(3)

💖 NAME 💖

okay so bestie, this is the ExtUtils::Depends(3) page from the User Contributed Perl Documentation — and it’s literally here to make one thing easy: ExtUtils::Depends - Easily build XS extensions that depend on XS extensions. that’s the whole NAME vibe. iconic. ✨

🎀 SYNOPSIS 🎀

        use ExtUtils::Depends;
        $package = new ExtUtils::Depends ('pkg::name', 'base::package')
        # set the flags and libraries to compile and link the module
        $package->set_inc("-I/opt/blahblah");
        $package->set_libs("-lmylib");
        # add a .c and an .xs file to compile
        $package->add_c('code.c');
        $package->add_xs('module-code.xs');
        # add the typemaps to use
        $package->add_typemaps("typemap");
        # install some extra data files and headers
        $package->install (qw/foo.h data.txt/);
        # save the info
        $package->save_config('Files.pm');

        WriteMakefile(
                'NAME' => 'Mymodule',
                $package->get_makefile_vars()
        );

🌸 DESCRIPTION 🌸

so the whole point: this module tries to make it easy to build Perl extensions that use functions and typemaps provided by other perl extensions. basically a perl extension gets treated like a shared library that also hands you a C and an XS interface besides the perl one. slay. 💅

This works as long as the base (or "producing") extension is loaded with the RTLD_GLOBAL flag — usually done with this in the main .pm file:

sub dl_load_flags {0x01}

...if you need to use functions defined in the module. That "producing" extension also has to tell ExtUtils::MakeMaker which specific functions to export, with arguments to WriteMakefile like:

  FUNCLIST => [qw(function_name)],
  DL_FUNCS => { 'Extension::Name' => [] },

The basic scheme of operation is: collect info about a module in the instance, then store that data in the Perl library where it may be retrieved later. The object can also reformat this information into the data structures that ExtUtils::MakeMaker's WriteMakefile function requires. 🫶

For the deets on how to make your module fit into this scheme, see hashref = ExtUtils::Depends::load (name).

When you create a new Depends object, you give it a name — the name of the module you are building. You can also specify the names of modules your module depends on. Those dependencies get loaded automatically, and their typemaps, header files, etc. get merged with your new object's stuff. When you store the data for your object, the list of dependencies gets stored with it, so another module depending on yours needn't know exactly which modules yours depends on. iykyk. 🔥

For example:

Gtk2 depends on Glib

Gnome2::Canvas depends on Gtk2

ExtUtils::Depends->new ('Gnome2::Canvas', 'Gtk2');
   this command automatically brings in all the stuff needed
   for Glib, since Gtk2 depends on it.

When the configuration info is saved, it also includes a class method called Inline, inheritable by your module. That lets your module simply say at the top:

package Mymod;
use parent 'Mymod::Install::Files'; # to inherit 'Inline' method

And users of Mymod who want to write inline code (using Inline) can simply write:

use Inline with => 'Mymod';

And all the necessary header files, defines, and libraries get added for them. no cap. 🌈

The Mymod::Install::Files will also implement a deps method, which returns a list of any modules that Mymod depends on — you will not normally need to use this:

require Mymod::Install::Files;
@deps = Mymod::Install::Files->deps;

🔧 METHODS 🔧

• $object = ExtUtils::Depends->new($name, @deps) — creates a new depends object named $name. Any modules listed in @deps (which may be empty) get added as dependencies, and their dependency information is loaded. If any dependency information can't be loaded, an exception is raised. 💀
• $depends->add_deps (@deps) — adds the modules listed in @deps as dependencies. 🎀
• (hashes) = $depends->get_deps — fetches info on the dependencies of $depends as a hash of hashes, which are dependency information indexed by module name. See load. 👀
• $depends->set_inc (@newinc) — adds strings to the includes or cflags variables.
• $depends->set_libs (@newlibs) — adds strings to the libs (linker flags) variable.
• $depends->add_pm (%pm_files) — adds files to the hash to be passed through ExtUtils::WriteMakefile's PM key.
• $depends->add_xs (@xs_files) — adds xs files to be compiled.
• $depends->add_c (@c_files) — adds C files to be compiled.
• $depends->add_typemaps (@typemaps) — adds typemap files to be used and installed.
• $depends->add_headers (list) — no-op, for backward compatibility. it's giving legacy support 🫡
• $depends->install (@files) — installs @files to the data directory for $depends. This actually works by adding them to the hash of pm files that gets passed through WriteMakefile's PM key. 📦
• $depends->save_config ($filename) — saves the important information from $depends to $filename, and sets it up to be installed as name::Install::Files.

Note: the actual value of $filename is unimportant so long as it doesn't clash with any other local files. It will be installed as name::Install::Files.

• hash = $depends->get_makefile_vars — returns the information in $depends in a format digestible by WriteMakefile. This sets at least these keys:

INC
LIBS
TYPEMAPS
PM

And these if there is data to fill them:

clean
OBJECT
XS

• hashref = ExtUtils::Depends::load (name) — loads and returns dependency information for name. Croaks if no such information can be found. The info comes back as an anonymous hash containing these keys:
  • instpath — the absolute path to the data install directory for this module.
  • typemaps — list of absolute pathnames for this module's typemap files.
  • inc — CFLAGS string for this module.
  • libs — LIBS string for this module.
  • deps — list of modules on which this one depends. This key will not exist when loading files created by old versions of ExtUtils::Depends. 🕰️

If you want to make module name support this, you must provide a module name::Install::Files, which on loading will implement these class methods:

$hashref = name::Install::Files->Inline('C');
# hash to contain any necessary TYPEMAPS (array-ref), LIBS, INC
@deps = name::Install::Files->deps;
# any modules on which "name" depends

An easy way to achieve this is to use the method $depends->save_config ($filename), but your package may have different facilities already. 💖

• $depends->load_deps — loads $depends dependencies, by calling load on each dependency module. This is usually done for you, and should only be needed if you want to call get_deps after calling add_deps manually. 🧚

🛟 SUPPORT 🛟

🐛 Bugs/Feature Requests 🐛

Version 0.2 discards some of the more esoteric features provided by the older versions. As they were completely undocumented, and this module has yet to reach 1.0, this may not exactly be a bug. 💀

This module is tightly coupled to the ExtUtils::MakeMaker architecture. no cap.

You can submit new bugs/feature requests by using one of two bug trackers (below). 👇

📮 CPAN Request Tracker 📮

You can submit bugs/feature requests via the web by going to <https://rt.cpan.org/Public/Bug/Report.html?Queue=ExtUtils-Depends> (requires PAUSE ID or Bitcard), or by sending an e-mail to bug-ExtUtils-Depends at rt.cpan.org.

🐞 Gnome.org Bugtracker 🐞

Report bugs/feature requests to 'perl-extutils-depends' (requires login) <https://gitlab.gnome.org/GNOME/perl-extutils-depends/-/issues/>.

Patches that implement new features with test cases, and/or test cases that exercise existing bugs are always welcome. 🫶

The Gtk-Perl support forum is at <https://discourse.gnome.org/tags/c/platform/language-bindings/11/perl>.

🌿 Source Code 🌿

The source code to ExtUtils::Depends is available at the Gnome.org Git repo (<https://gitlab.gnome.org/GNOME/perl-extutils-depends>). Create your own copy of the Git repo with:

git clone git://git.gnome.org/perl-ExtUtils-Depends (Git protocol)
git clone https://git.gnome.org/browse/perl-ExtUtils-Depends/ (HTTPS)

👀 SEE ALSO 👀

ExtUtils::MakeMaker. that's it. periodt. 💅

✍️ AUTHOR ✍️

Paolo Molaro <lupus at debian dot org> wrote the original version for Gtk-Perl. muppet <scott at asofyet dot org> rewrote the innards for version 0.2, borrowing liberally from Paolo's code. iconic collaboration. 💖

👑 MAINTAINER 👑

The Gtk2 project, <http://gtk2-perl.sf.net>/"gtk-perl-list at gnome dot org". 🫶

📜 LICENSE 📜

This library is free software; you may redistribute it and/or modify it under the same terms as Perl itself. 🌸

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okay bestie, that’s the whole page: source/version is perl v5.42.0, dated 2025-07-25, and it’s the ExtUtils::Depends(3) manpage. go build something iconic, mwah 💋✨