Vala - Compiler for the GObject type system

Contents

  1. Vala - Compiler for the GObject type system
    1. Introduction
    2. News
    3. Why Vala?
    4. Current Status
    5. Tool Support
    6. IDE Support
    7. License
    8. Documentation
    9. Tutorials
    10. Bindings
    11. Other Resources
    12. Sample Code
    13. Projects Developed in Vala
    14. Download
    15. Requirements
    16. Contact

Introduction

Vala is a new programming language that aims to bring modern programming language features to GNOME developers without imposing any additional runtime requirements and without using a different ABI compared to applications and libraries written in C.

News

valac, the Vala compiler, is a self-hosting compiler that translates Vala source code into C source and header files. It uses the GObject type system to create classes and interfaces declared in the Vala source code.

The syntax of Vala is similar to C#, modified to better fit the GObject type system. Vala supports modern language features as the following:

Vala is designed to allow access to existing C libraries, especially GObject-based libraries, without the need for runtime bindings. All that is needed to use a library with Vala is an API file, containing the class and method declarations in Vala syntax. Vala currently comes with experimental bindings for GLib and GTK+. It's planned to provide generated bindings for the full GNOME Platform at a later stage.

Using classes and methods written in Vala from an application written in C is not difficult. The Vala library only has to install the generated header files and C applications may then access the GObject-based API of the Vala library as usual. It should also be easily possible to write a bindings generator for access to Vala libraries from applications written in e.g. C# as the Vala parser is written as a library, so that all compile-time information is available when generating a binding.

Why Vala?

Many developers want to write GNOME applications and libraries in high-level programming languages but can't or don't want to use C# or Java for various reasons, so they are stuck with C without syntax support for the GObject type system. The Vala compiler allows developers to write complex object-oriented code rapidly while maintaining a standard C API and ABI and keeping the memory requirements low.

C# and Java libraries can't be used the same way as native GObject libraries from C and other languages and can't be accepted as part of the GNOME Platform. Managed applications also suffer from usually higher memory requirements which is not acceptable in some situations.

valac produces C source and header files from Vala source files as if you've written your library or application directly in C. Using a Vala library from a C application won't look different than using any other GObject-based library. There won't be a vala runtime library and applications can distribute the generated C code with their tarballs, so there are no additional run- or build-time dependencies for users.

Current Status

The Vala compiler is self-hosting since the end of May 2006. It is capable of compiling small and large Vala applications using Gtk+ and other libraries. There is still a lot to do, though, to complete the compiler: we need to implement more semantic checks and fix more bugs as we find them. You're encouraged to test it out and provide feedback about the language or the compiler.

Tool Support

IDE Support

There are various projects in various states of stability in order to provide IDE support for Vala:

License

The Vala compiler is licensed under the LGPL 2.1+

Documentation

We're still working on documenting the whole language. The current draft can be found at http://www.vala-project.org/doc/vala/

There is also a more complete but less checked draft in the wiki at Manual. This version covers most of the language and is heavily annotated, but may contain mistakes.

Tutorials

If you want some tips before start hacking in Vala, take a tutorial and see what you can do with this.

If you find any mistakes in the tutorials please feel free to correct them.

Bindings

Other Resources

Sample Code

If you have trouble compiling an example try the latest release of Vala. Some distributions ship with older versions of Vala which may lack some features. Also make sure that the respective libraries are installed along with their header files (e.g. *-devel packages on RedHat/Fedora/SuSE, *-dev packages on Debian/Ubuntu).

More code samples on http://code.valaide.org/

Projects Developed in Vala

Vala Specific

Applications / Applets / Other Projects

Download

Releases can be found on /Release. There's a community maintained Vala PPA for Ubuntu on Launchpad and someone is maintaining Windows binaries.

Development is happening in git://git.gnome.org/vala and can be viewed here.

You can check out the current development snapshot using (please note, that you need vala installed to build it from git): 

 git clone git://git.gnome.org/vala

or, if you have an account on gnome.org: 

 git clone ssh://<username>@git.gnome.org/git/vala

Requirements

Contact

There is a mailing list for developer and general discussions. The list can also be read and posted to via gmane using their web or news interface. There is also an IRC channel #vala on GIMPnet (irc.gimp.org). Bugs can be reported in Vala bugzilla page.

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Vala (last edited 2010-07-28 08:23:04 by Frederik)