Exemplo n.º 1
0
  private void narrowByRule(ConstrainedTerm constrainedTerm, Rule rule) {
    stopwatch.reset();
    stopwatch.start();

    constrainedTermResults = new ArrayList<ConstrainedTerm>();

    SymbolicConstraint leftHandSideConstraint =
        new SymbolicConstraint(constrainedTerm.termContext());
    leftHandSideConstraint.addAll(rule.requires());
    for (Variable variable : rule.freshVariables()) {
      leftHandSideConstraint.add(variable, IntToken.fresh());
    }

    ConstrainedTerm leftHandSide =
        new ConstrainedTerm(
            rule.leftHandSide(),
            rule.lookups().getSymbolicConstraint(constrainedTerm.termContext()),
            leftHandSideConstraint,
            constrainedTerm.termContext());

    for (SymbolicConstraint constraint : constrainedTerm.unify(leftHandSide)) {
      constraint.addAll(rule.ensures());
      /* rename rule variables in the constraints */
      Map<Variable, Variable> freshSubstitution = constraint.rename(rule.variableSet());

      Term result = rule.rightHandSide();
      /* rename rule variables in the rule RHS */
      result = result.substituteWithBinders(freshSubstitution, constrainedTerm.termContext());
      /* apply the constraints substitution on the rule RHS */
      result =
          result.substituteWithBinders(constraint.substitution(), constrainedTerm.termContext());
      /* evaluate pending functions in the rule RHS */
      result = result.evaluate(constrainedTerm.termContext());
      /* eliminate anonymous variables */
      constraint.eliminateAnonymousVariables();

      /* compute all results */
      constrainedTermResults.add(
          new ConstrainedTerm(result, constraint, constrainedTerm.termContext()));
    }

    stopwatch.stop();
  }
Exemplo n.º 2
0
  // apply rule by matching
  private void rewriteByRule(Term term, Rule rule) {
    stopwatch.reset();
    stopwatch.start();

    termResults = new ArrayList<Term>();

    TermContext context = TermContext.of(definition);
    ConstrainedTerm constrainedTerm = new ConstrainedTerm(term, context);

    SymbolicConstraint leftHandSideConstraint = new SymbolicConstraint(context);
    leftHandSideConstraint.addAll(rule.requires());
    for (Variable variable : rule.freshVariables()) {
      leftHandSideConstraint.add(variable, IntToken.fresh());
    }

    ConstrainedTerm leftHandSide =
        new ConstrainedTerm(
            rule.leftHandSide(),
            rule.lookups().getSymbolicConstraint(context),
            leftHandSideConstraint,
            context);

    for (SymbolicConstraint constraint : constrainedTerm.unify(leftHandSide)) {
      if (!constraint.isMatching(leftHandSide)) {
        continue;
      }

      constraint.orientSubstitution(leftHandSide.variableSet());

      Term result = rule.rightHandSide();
      /* apply the constraints substitution on the rule RHS */
      result = result.substituteAndEvaluate(constraint.substitution(), context);

      /* compute all results */
      termResults.add(result);
    }

    stopwatch.stop();
  }