Marco Trillo

• Documents
• Experiments
  • SILXPI: a simple logic programming interpreter
  • SLSIC: a really simple functional language
  • BSD stuff
  • Mac OS applications
  • Other stuff

Documents

• Notas sobre lógica y semántica declarativa de la programación lógica (In Spanish). Last revision: April 19 2009.
  • PDF version
  • PostScript version (gzipped)

Experiments

The following are various software experiments I develop just for fun.

SILXPI: a simple logic programming interpreter

silxpi is an interpreter for a logic programming language which is a subset of Prolog.

It implements unification without ocurr-check and SLD resolution. In addition to the "pure Prolog" subset it also implements the Cut symbol with usual Prolog semantics, and extra-logical built-in predicates (such as consult/1, write/1 or fail/0).
It's written in C and should compile and work on any UNIX system.

• SILXPI 1.6 source code (.tar.gz) (August 31, 2009).

In SILXPI 1.6, the engine has been completely rewritten and it is a lot faster than previous versions. It also features automatic memory management.

Example: queens.prl (N-queens problem).

Example of an interactive interpreter session:

$ ./silxpi 
SILXPI 1.6 - a simple logic program interpreter (a la Prolog).

?- consult(user).
/* user file. type ^L to return. */
takeout(X,[X|R],R).
takeout(X,[F|R],[F|S]) :- takeout(X,R,S).
perm([X|Y],Z) :- perm(Y,W), takeout(X,Z,W).   
perm([],[]).
^L

yes
?- perm([1,2,3],P).

P = [1,2,3] ? ;

P = [2,1,3] ? ;

P = [2,3,1] ? ;

P = [1,3,2] ? ;

P = [3,1,2] ? ;

P = [3,2,1] ? ;
no
?- ^D

SLSIC: a really simple functional language

slsic is a very simple interpreter for a functional language. It is implemented in just 1000 lines of C89 source code and contains support for lambda expressions , (recursive) ordered pairs, definitions, atoms (any arbitrary symbolic identifier can be used), pattern matching ...

This interpreter is not available currently.

Example: bina.sic.

BSD stuff

This is stuff I use in my BSD systems:

• Apple Onboard Audio driver for FreeBSD/powerpc: now available on FreeBSD 8.0 and later (see snd_davbus(4) and snd_ai2s(4)).
• adbii(4), a cleanup of the VIA macII ADB driver in NetBSD/mac68k to use the new nadb(4) subsystem, which is shared with NetBSD/macppc. The state machine is simplified and keyboard leds work.
• snd, a sound device with the goal of being minimalist (no format or resampling done, it is just a hardware access layer) and MP-safe, for using on NetBSD 5 and later. Files: snd.c sndio.h snd_if.h.

Mac OS applications

• Mahjong Solitaire 3.0 (BinHexed Disk Copy image of 800K floppy).

  This is a mahjong solitaire game that works on classic Macintosh models. Minimum system requirements:

  • Macintosh 512Ke or better.
  • System Software 5.0 or later [works in System 6 :-)].

  Includes source code and MPW Makefile.

Other stuff

• FAG/GFX 1-bit graphical library.
• DigitalLogic 1.0 (Win32 binary), a simple digital logic program for Windows in which various digital gates can be placed on the board and wires can be used to connect components, which can be used to construct a digital system.
  
  It supports a LED gate to display the digital value of a wire, SWITCH and GND gates to set the value of a wire, basic digital gates (AND, OR, NOT, NOR, etc.), a CLOCK gate which generates a square-wave synchronization signal, a JK flip-flop etc. This a beta and incomplete version (lacks some important features), but should be otherwise usable.
• libb64 library.
• libieee754 library.
• AIFF Audio Tools.
• Xeganograph.

Last updated: August 31, 2009