[An Alpha star]

Features of Alfa

Alfa is a largely inspired by Window-Alf, implemented by Lena Magnusson and Johan Nordlander, and has a similar user interface.

The plan is that Alfa should improve on Window-Alf by

Many of these features are available in the current version of Alfa, although some of them are still in a experimental stage of development.

Below you can read more about:



Limitations of the current version

Before you start playing with Alfa, please note that Alfa and that

About the implementation of Alfa

(Not updated recently.)

Whereas Window-Alf was implemented in Standard ML (proof engine) and C++ & Interviews (user interface), Alfa is implemented entirely in Haskell, using Fudgets for the user interface. The source code currently (16 April 1996) consists of about 6000 lines, distributed as follows:

Update 10 April 1997: The total size now is 9500 lines. This includes 2100 lines from Aarne Ranta with support for natural language.

Update 18 March 1999: The total size now is 16738 lines. The proof engine (Agda) consists of 9999 lines. The rest, 6739 lines, is user interface stuff. (Aarne Ranta's stuff is currently not part of Alfa.)

Update 27 February 2000: The total size now is 18756 lines. Agda consists of 10548 lines. The user interface is 8208 lines. GF, which is included through the plugin interface, is 5802 lines long.