public TermFunction ReplaceVariablesAndConstants(Term function)
{
var assignment = new Substitution();
var termsToReplace = new HashSet<Term>();
GdlVisitors.VisitTerm(function, new GdlVisitor
{
VisitConstant = constant => termsToReplace.Add(constant),
VisitVariable = variable => termsToReplace.Add(variable)
});
foreach (TermVariable var in GetVariables(function))
assignment.AddMapping(var, GetUnusedVariable());
return (TermFunction)function.ApplySubstitution(assignment);
}
public Substitution GetReplacementAssignment(Fact sentence, UnusedVariableGenerator varGen)
{
Debug.Assert(Applies(sentence));
var assignment = new Substitution();
List<Term> tuple = sentence.NestedTerms.ToList();
foreach (int varIndex in _replacementsByOriginalTupleIndex.Keys)
{
TermFunction function = _replacementsByOriginalTupleIndex[varIndex];
TermFunction replacementFunction = varGen.ReplaceVariablesAndConstants(function);
assignment.AddMapping((TermVariable)tuple[varIndex], replacementFunction);
}
return assignment;
}