gf-core/index.txt

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[doc/gf-logo.png]

=Grammatical Framework=

Version 3.0

June 2008


#BELARGE

``[`` [Demos demos/index.html]
``|`` [Download download/index.html]
``|`` [Libraries lib/resource/doc/synopsis.html]
``|`` [Reference doc/gf-refman.html]
``|`` [Tutorial doc/gf-tutorial.html]
``]`` 

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``[`` [Demos demos/index.html]
``|`` [Download download/index.html]
``|`` [Developers doc/gf-developers.html]
% ``|`` [Events doc/events.html]
``|`` [Libraries lib/resource/doc/synopsis.html]
``|`` [People doc/gf-people.html]
% ``|`` [Projects doc/projects.html]
``|`` [Publications doc/gf-bibliography.html]
``|`` [QuickRefCard doc/gf-reference.html]
``|`` [Reference doc/gf-refman.html]
``|`` [Tutorial doc/gf-tutorial.html]
``]`` 

#ENCE


#BESMALL

==News==

20 April 2009:
On-line course "GF for Resource Grammar Writers" starting today at 15.30. See the
[Summer School Google Group http://groups.google.com/group/gf-resource-school-2009]
for instructions how to start.

3 April 2009: 
Two demos and one talk on GF at [EACL http://www.eacl2009.gr/conference/] in Athens.

20 February 2009: 
[GF Resource Grammar Summer School doc/gf-summerschool.html] 
in Gothenburg, 17-28 August 2009.

4 November 2008: 
GHC 6.10 released, but it doesn't work with GF sources yet.
If compiling GF from source, use e.g.
[GHC 6.8.3 http://haskell.org/ghc/download_ghc_683.html].

15 August 2008:
[Numeral translator for the iPhone demos/index-numbers.html]

27 June 2008: 
[release of GF 3.0 doc/gf3-release.html] and this new web page; the old web page is 
[here ../GF2/index.html].


#ENSMALL


==What is GF==

GF, Grammatical Framework, is a programming language for 
**multilingual grammar applications**. It is
- a **special-purpose language for grammars**, like YACC, Bison, Happy, BNFC, 
  but not restricted to programming languages
- a **functional language**, like Haskell, Lisp, OCaml, Scheme, SML,
  but specialized to grammar writing
- a **natural language processing framework**, like LKB, XLE, Regulus,
  but based on functional programming and type theory
- a **categorial grammar formalism**, like ACG, CCG,
  but different and equipped with different tools
- a **logical framework**, like Agda, Coq, Isabelle,
  but equipped with concrete syntax in addition to logic


Don't worry if you don't know most of the references above - but if you do know at
least one, it may help you to get a first idea of what GF is.


==Applications==

GF can be used for building
- [text translators lib/resource/doc/resdemo.html]
- [speech translators http://www.cs.chalmers.se/~bringert/gf/translatespeech.html]
- [natural-language interfaces http://www.cs.chalmers.se/~hallgren/Alfa/Tutorial/GFplugin.html]
- [multilingual web pages http://www.restauranggajden.se/tomas/]
- [multilingual authoring systems http://www.cs.chalmers.se/~markus/gramlets/letter-applet.html]
- [dialogue systems http://www.cs.chalmers.se/~bringert/xv/pizza/]
- [language training systems http://csmisc14.cs.chalmers.se/~bjorn/langtrain.cgi]
- [natural language resources lib/resource/doc/synopsis.html]


==Availability==

GF is **open-source**, licensed under [GPL LICENSE] (the program) and 
[LGPL lib/LICENSE] (the libraries). It
is available for 
- Linux
- Mac OS X
- Windows
- via compilation to JavaScript, almost any platform that has a web browser


==Projects==

GF was first created in 1998 at 
[Xerox Research Centre Europe http://www.xrce.xerox.com/], 
Grenoble, in the project
Multilingual Document Authoring. At Xerox, it was used for prototypes including
a restaurant phrase book,
a database query system,
a formalization of an alarm system instructions with translations to 5 languages, and
an authoring system for medical drug descriptions.

Later projects using GF and involving third parties include, in chronological order,
- [GF-Alfa http://www.cs.chalmers.se/~hallgren/Alfa/Tutorial/GFplugin.html]: 
  natural language interface to formal proofs
- [Efficient http://efficient.citi.tudor.lu/index_noframe.html]:
  authoring tool for business models.
- [GF-KeY http://www.key-project.org/]: 
  authoring and translation of software specifications
- [TALK http://www.talk-project.org]: 
  multilingual and multimodal spoken dialogue systems
- [WebALT http://webalt.math.helsinki.fi/]: 
  multilingual generation of mathematical exercises (commercial project)
- [SALDO http://spraakbanken.gu.se/sal/]: 
  Swedish morphological dictionary based on rules developed for GF and
  [Functional Morphology http://www.cs.chalmers.se/~markus/FM/]


Academically, GF has been used in four PhD theses and resulted in around
fifty scientific publications (see [GF publication list doc/gf-bibliography.html]).


==Programming in GF==

GF is easy to learn by following the [tutorial doc/gf-tutorial.html]. 
You can write your first translator in 15 minutes.

GF has an interactive command interpreter, as well as a batch compiler. 
Grammars can be compiled to parser and translator code in many different 
formats.  These components can then be embedded in applications written 
in other programming languages. The formats currently supported are:
- Haskell
- Java
- JavaScript
- Prolog
- Speech recognition: HTK/ATK, Nuance, JSGF


The GF programming language is high-level and advanced, featuring
- static type checking
- higher-order functions
- dependent types
- pattern matching with data constructors and regular expressions
- module system with multiple inheritance and parametrized modules


==Libraries==

Libraries are at the heart of modern software engineering. In natural language 
applications, libraries are a way to cope with thousands of details involved in
syntax, lexicon, and inflection. The 
[GF resource grammar library lib/resource/doc/synopsis.html] has
support for an increasing number of languages, currently including
+ Arabic (partial)
+ Bulgarian
+ Catalan (partial)
+ Danish
+ English
+ Finnish
+ French
+ German 
+ Hindi/Urdu (fragments)
+ [Interlingua http://www.interlingua.com/]
+ Italian
+ Norwegian bokm<6B>l
+ Russian
+ Spanish
+ Swedish
+ Thai (fragments)


Adding a language to the resource library takes 3 to 9 
months - contributions 
are welcome!

% [doc/10lang-small.png]