# ;; -*- mode: org; coding: utf-8 -*-

#+TITLE: GNU G-Golf README

#+BEGIN_COMMENT

Copyright (C) 2016 - 2025
Free Software Foundation, Inc.

This document is part of GNU G-Golf.

Copying and distribution of this file, with or without modification, are
permitted in any medium without royalty provided the copyright notice
and this notice are preserved.  This file is offered as-is, without any
warranty.

#+END_COMMENT


                            G-Golf - README
              ===========================================

                   Please send G-Golf bug reports to
                           bug-g-golf@gnu.org


* GNU G-Golf

[[http://www.gnu.org/software/g-golf][G-Golf]]
GNOME: (Guile Object Library for).

** Description

[[http://www.gnu.org/software/g-golf][G-Golf]] is a [[https://www.gnu.org/software/guile/][Guile]] Object Library for [[https://www.gnome.org/][GNOME]].

G-Golf is tool to develop fast and feature-rich graphical applications,
with a recognizable look and feel. Here is an overview of the [[https://developer.gnome.org/documentation/introduction/overview/libraries.html][GNOME
platform libraries]], accessible using G-Golf.

In particular, [[https://gnome.pages.gitlab.gnome.org/libadwaita/doc/main/][libadwaita]] provides a number of widgets that change their
layout based on the available space. This can be used to make
applications adapt their UI between desktop and mobile devices. The
[[https://wiki.gnome.org/Apps/Web][GNOME Web]] (best known through its code name, Epiphany, is a good example
of such an adaptive UI.

G-Golf uses [[https://docs.gtk.org/glib/index.html][GLib]], [[https://docs.gtk.org/gobject/index.html][GObject]] and [[https://gi.readthedocs.io/en/latest/][GObject Introspection]]. As it imports a
[[https://gi.readthedocs.io/en/latest/][Typelib]] (a GObject introspectable library), G-Golf defines GObject
classes as Guile Object Oriented System ([[https://www.gnu.org/software/guile/manual/html_node/GOOPS.html#GOOPS][GOOPS]]) classes. GObject methods
are defined and added to their corresponding generic function. Simple
functions are defined as scheme procedures.

Here is an example, an excerpt taken from the peg-solitaire game, that
shows the implementation, for the peg-solitaire game, of the
GtkApplication activate signal callback in G-Golf:

#+BEGIN_SRC scheme
(define (activate app)
  (let ((window (make <gtk-application-window>
                  #:title "Peg Solitaire"
                  #:default-width 420
                  #:default-height 420
                  #:application app))
        (header-bar (make <gtk-header-bar>))
        (restart (make <gtk-button>
                   #:icon-name "view-refresh-symbolic")))

    (connect restart
             'clicked
             (lambda (bt)
               (restart-game window)))

    (set-titlebar window header-bar)
    (pack-start header-bar restart)
    (create-board window)
    (show window)))
#+END_SRC

G-Golf comes with some examples, listed on the [[https://www.gnu.org/software/g-golf/learn.html][learn page]] of the G-Golf
web site. Each example comes with a screenshot and has a link that
points to its source code, in the G-Golf sources [[http://git.savannah.gnu.org/cgit/g-golf.git][repository]].

** Latest News

Feb 2025

GNU G-Golf version 0.8.0 released.

Visit the NEWS file or see the [[http://git.savannah.gnu.org/cgit/g-golf.git/tree/NEWS][News]] page for the list of visible changes
in this release, as well as older news.

** Savannah

GNU G-Golf also has a [[https://savannah.gnu.org/][Savannah]] project page, [[https://savannah.gnu.org/projects/g-golf/][here]].

** Join the GNU Project

GNU G-Golf is part of the GNU Operating System, developed by the GNU
Project.

If you are the author of an awesome program and want to join us in
writing Free (libre) Software, please consider making it an official
GNU program and become a GNU Maintainer. You can find instructions
on how to do this [[https://www.gnu.org/help/evaluation][here]].

You don't have a program to contribute? Look at all the other ways you
still may [[https://www.gnu.org/help/help][help]].

To learn more about Free (libre) Software, you can read and please share
[[https://gnu.org/philosophy/free-sw.html][this page]].

** License

GNU G-Golf is a free software, distributed under the terms of the GNU
Lesser General Public License LGPLv3 or higher. You must be aware there
is no warranty whatsoever for GNU G-Golf. This is described in full in
the license.
