fixes for python language binding, added python example

2 files changed, 63 insertions, 0 deletions

diff --git a/examples/Makefile.am b/examples/Makefile.am
index 3e05d480d..f72c20d02 100644
--- a/examples/Makefile.am
+++ b/examples/Makefile.am
@@ -51,6 +51,7 @@ SimpleVCCompat.class: SimpleVCCompat.java
 
 EXTRA_DIST = \
 	SimpleVC.java \
+	SimpleVC.py \
 	SimpleVCCompat.java \
 	README
 
diff --git a/examples/SimpleVC.py b/examples/SimpleVC.py
new file mode 100644
index 000000000..2a4fc2e5e
--- /dev/null
+++ b/examples/SimpleVC.py
@@ -0,0 +1,62 @@
+######################                                                        ##
+##! \file SimpleVC.py
+### \verbatim
+### Original author: mdeters
+### Major contributors: none
+### Minor contributors (to current version): none
+### This file is part of the CVC4 prototype.
+### Copyright (c) 2009, 2010, 2011  The Analysis of Computer Systems Group (ACSys)
+### Courant Institute of Mathematical Sciences
+### New York University
+### See the file COPYING in the top-level source directory for licensing
+### information.\endverbatim
+###
+### \brief A simple demonstration of the Python interface
+###
+### A simple demonstration of the Python interface.  Compare to the
+### C++ interface in simple_vc_cxx.cpp; they are quite similar.
+###
+### To run, use something like:
+###
+###   PYTHONPATH=/dir/containing/CVC4.py:$PYTHONPATH \
+###   python \
+###     -Djava.library.path=/dir/containing/libcvc4bindings_python.so \
+###     SimpleVC
+####
+
+from ctypes import cdll
+cdll.LoadLibrary('libcvc4.so')
+cdll.LoadLibrary('libcvc4parser.so')
+cdll.LoadLibrary('libcvc4bindings_python.so')
+import CVC4
+
+def main():
+  em = ExprManager()
+  smt = SmtEngine(em)
+
+  # Prove that for integers x and y:
+  #   x > 0 AND y > 0  =>  2x + y >= 3
+
+  integer = em.integerType()
+
+  x = em.mkVar("x", integer)
+  y = em.mkVar("y", integer)
+  zero = em.mkConst(Integer(0))
+
+  x_positive = em.mkExpr(kind.GT, x, zero)
+  y_positive = em.mkExpr(kind.GT, y, zero)
+
+  two = em.mkConst(Integer(2))
+  twox = em.mkExpr(kind.MULT, two, x)
+  twox_plus_y = em.mkExpr(kind.PLUS, twox, y)
+
+  three = em.mkConst(Integer(3))
+  twox_plus_y_geq_3 = em.mkExpr(kind.GEQ, twox_plus_y, three)
+
+  formula = BoolExpr(em.mkExpr(kind.AND, x_positive, y_positive)).impExpr(BoolExpr(twox_plus_y_geq_3))
+
+  print "Checking validity of formula " << formula << " with CVC4." << endl
+  print "CVC4 should report VALID." << endl
+  print "Result from CVC4 is: " << smt.query(formula) << endl
+
+  return 0