decreasoner is a Discrete Event Calculus reasoner written by Erik T. Mueller (author of “Commonsense Reasoning“). This is how I build it on OpenBSD 4.7:

  • tar zxf ply-3.3.tar.gz
  • tar zxf decreasoner.tar.gz
  • cd decreasoner/software/relsat-dist/
  • tar zxf ../../../relsat_2.02.tar
  • gmake -f Makefile.linux
  • cp ./relsat ../../solvers/
  • cd ../..
  • cp ../ply-3.3/ply/lex.py .
  • cp ../ply-3.3/ply/yacc.py .
  • decreasoner.py executes sort -g. Unfortunatelly, OpenBSD’s sort does not support a -g switch and you have to change it to -n. See also a discussion of sort -g vs sort -n.
  • ./make.sh

Someday I think I may contribute a script that may (semi)automate the above…