Examples with NaryFormula kodkod.ast.NaryFormula used on opensource projects

Example 1 with NaryFormula

use of kodkod.ast.NaryFormula in project org.alloytools.alloy by AlloyTools.

the class Nodes method roots.

/**
 * Returns the roots of the given formula. In other words, breaks up the given
 * formula into its conjunctive components, {f0, ..., fk}, such that, for all
 * 0<=i<=k, f<sub>i</sub> is not a conjunction and [[f0 && ... && fk]] <=>
 * [[formula]].
 *
 * @return subformulas, {f0, ..., fk}, of the given formula such that, for all
 *         0<=i<=k, f<sub>i</sub> is not a conjuction and [[f0 && ... && fk]]
 *         <=> [[formula]].
 */
public static Set<Formula> roots(Formula formula) {
    final List<Formula> formulas = new LinkedList<Formula>();
    formulas.add(formula);
    final ListIterator<Formula> itr = formulas.listIterator();
    while (itr.hasNext()) {
        final Formula f = itr.next();
        if (f instanceof BinaryFormula) {
            final BinaryFormula bin = (BinaryFormula) f;
            if (bin.op() == FormulaOperator.AND) {
                itr.remove();
                itr.add(bin.left());
                itr.add(bin.right());
                itr.previous();
                itr.previous();
            }
        } else if (f instanceof NaryFormula) {
            final NaryFormula nf = (NaryFormula) f;
            if (nf.op() == FormulaOperator.AND) {
                itr.remove();
                for (Formula child : nf) {
                    itr.add(child);
                }
                for (int i = nf.size(); i > 0; i--) {
                    itr.previous();
                }
            }
        }
    }
    return new LinkedHashSet<Formula>(formulas);
}

Example 2 with NaryFormula

use of kodkod.ast.NaryFormula in project org.alloytools.alloy by AlloyTools.

the class FOL2BoolTranslator method visit.

/**
 * Calls lookup(formula) and returns the cached value, if any. If a translation
 * has not been cached, translates the formula, calls cache(...) on it and
 * returns it.
 *
 * @return let t = lookup(formula) | some t => t, cache(formula,
 *         formula.op(formula.left.accept(this), formula.right.accept(this))
 */
@Override
public final BooleanValue visit(NaryFormula formula) {
    final BooleanValue ret = lookup(formula);
    if (ret != null)
        return ret;
    final FormulaOperator op = formula.op();
    final Operator.Nary boolOp;
    switch(op) {
        case AND:
            boolOp = Operator.AND;
            break;
        case OR:
            boolOp = Operator.OR;
            break;
        default:
            throw new IllegalArgumentException("Unknown nary operator: " + op);
    }
    final BooleanAccumulator acc = BooleanAccumulator.treeGate(boolOp);
    final BooleanValue shortCircuit = boolOp.shortCircuit();
    for (Formula child : formula) {
        if (acc.add(child.accept(this)) == shortCircuit)
            break;
    }
    return cache(formula, interpreter.factory().accumulate(acc));
}

Example 3 with NaryFormula

use of kodkod.ast.NaryFormula in project org.alloytools.alloy by AlloyTools.

the class Skolemizer method visit.

/**
 * If not cached, visits the formula's children with appropriate settings for
 * the negated flag and the skolemDepth parameter.
 *
 * @see kodkod.ast.visitor.AbstractReplacer#visit(kodkod.ast.NaryFormula)
 */
@Override
public final Formula visit(NaryFormula bf) {
    Formula ret = lookup(bf);
    if (ret != null)
        return ret;
    final int oldDepth = skolemDepth;
    final FormulaOperator op = bf.op();
    switch(op) {
        case AND:
            if (negated)
                skolemDepth = -1;
            break;
        case OR:
            if (!negated)
                skolemDepth = -1;
            break;
        default:
            throw new IllegalArgumentException("Unknown nary operator: " + op);
    }
    final Formula[] visited = new Formula[bf.size()];
    boolean allSame = true;
    for (int i = 0; i < visited.length; i++) {
        final Formula child = bf.child(i);
        visited[i] = child.accept(this);
        allSame = allSame && (child == visited[i]);
    }
    ret = allSame ? bf : Formula.compose(op, visited);
    skolemDepth = oldDepth;
    return source(cache(bf, ret), bf);
}

Example 4 with NaryFormula

use of kodkod.ast.NaryFormula in project org.alloytools.alloy by AlloyTools.

the class AbstractReplacer method visit.

/**
 * Calls lookup(formula) and returns the cached value, if any. If a replacement
 * has not been cached, visits the formula's children. If nothing changes, the
 * argument is cached and returned, otherwise a replacement formula is cached
 * and returned.
 *
 * @return { e: Expression | e.op = formula.op && #e.children =
 *         #formula.children && all i: [0..formula.children) | e.child(i) =
 *         formula.child(i).accept(delegate) }
 */
@Override
public Formula visit(NaryFormula formula) {
    Formula ret = lookup(formula);
    if (ret != null)
        return ret;
    final Formula[] visited = new Formula[formula.size()];
    boolean allSame = true;
    for (int i = 0; i < visited.length; i++) {
        final Formula child = formula.child(i);
        visited[i] = child.accept(delegate);
        allSame = allSame && visited[i] == child;
    }
    ret = allSame ? formula : Formula.compose(formula.op(), visited);
    return cache(formula, ret);
}

Example 5 with NaryFormula

use of kodkod.ast.NaryFormula in project org.alloytools.alloy by AlloyTools.

the class TranslateKodkodToJava method countHeight.

/**
 * Count the height of the given Kodkod AST tree.
 */
public static int countHeight(Node node) {
    ReturnVisitor<Integer, Integer, Integer, Integer> vis = new ReturnVisitor<Integer, Integer, Integer, Integer>() {

        private int max(int a, int b) {
            return (a >= b) ? a : b;
        }

        private int max(int a, int b, int c) {
            return (a >= b) ? (a >= c ? a : c) : (b >= c ? b : c);
        }

        @Override
        public Integer visit(Relation x) {
            return 1;
        }

        @Override
        public Integer visit(IntConstant x) {
            return 1;
        }

        @Override
        public Integer visit(ConstantFormula x) {
            return 1;
        }

        @Override
        public Integer visit(Variable x) {
            return 1;
        }

        @Override
        public Integer visit(ConstantExpression x) {
            return 1;
        }

        @Override
        public Integer visit(NotFormula x) {
            return 1 + x.formula().accept(this);
        }

        @Override
        public Integer visit(IntToExprCast x) {
            return 1 + x.intExpr().accept(this);
        }

        @Override
        public Integer visit(Decl x) {
            return 1 + x.expression().accept(this);
        }

        @Override
        public Integer visit(ExprToIntCast x) {
            return 1 + x.expression().accept(this);
        }

        @Override
        public Integer visit(UnaryExpression x) {
            return 1 + x.expression().accept(this);
        }

        @Override
        public Integer visit(UnaryIntExpression x) {
            return 1 + x.intExpr().accept(this);
        }

        @Override
        public Integer visit(MultiplicityFormula x) {
            return 1 + x.expression().accept(this);
        }

        @Override
        public Integer visit(BinaryExpression x) {
            return 1 + max(x.left().accept(this), x.right().accept(this));
        }

        @Override
        public Integer visit(ComparisonFormula x) {
            return 1 + max(x.left().accept(this), x.right().accept(this));
        }

        @Override
        public Integer visit(BinaryFormula x) {
            return 1 + max(x.left().accept(this), x.right().accept(this));
        }

        @Override
        public Integer visit(BinaryIntExpression x) {
            return 1 + max(x.left().accept(this), x.right().accept(this));
        }

        @Override
        public Integer visit(IntComparisonFormula x) {
            return 1 + max(x.left().accept(this), x.right().accept(this));
        }

        @Override
        public Integer visit(IfExpression x) {
            return 1 + max(x.condition().accept(this), x.thenExpr().accept(this), x.elseExpr().accept(this));
        }

        @Override
        public Integer visit(IfIntExpression x) {
            return 1 + max(x.condition().accept(this), x.thenExpr().accept(this), x.elseExpr().accept(this));
        }

        @Override
        public Integer visit(SumExpression x) {
            return 1 + max(x.decls().accept(this), x.intExpr().accept(this));
        }

        @Override
        public Integer visit(QuantifiedFormula x) {
            return 1 + max(x.decls().accept(this), x.formula().accept(this));
        }

        @Override
        public Integer visit(FixFormula x) {
            return 1 + max(x.condition().accept(this), x.formula().accept(this));
        }

        @Override
        public Integer visit(Comprehension x) {
            return 1 + max(x.decls().accept(this), x.formula().accept(this));
        }

        @Override
        public Integer visit(Decls x) {
            int max = 0, n = x.size();
            for (int i = 0; i < n; i++) max = max(max, x.get(i).accept(this));
            return max;
        }

        @Override
        public Integer visit(ProjectExpression x) {
            int max = x.expression().accept(this);
            for (Iterator<IntExpression> t = x.columns(); t.hasNext(); ) {
                max = max(max, t.next().accept(this));
            }
            return max;
        }

        @Override
        public Integer visit(RelationPredicate x) {
            if (x instanceof Function) {
                Function f = ((Function) x);
                return max(f.domain().accept(this), f.range().accept(this));
            }
            return 1;
        }

        @Override
        public Integer visit(NaryExpression x) {
            int max = 0;
            for (int m = 0, n = x.size(), i = 0; i < n; i++) {
                m = x.child(i).accept(this);
                if (i == 0 || max < m)
                    max = m;
            }
            return max + 1;
        }

        @Override
        public Integer visit(NaryIntExpression x) {
            int max = 0;
            for (int m = 0, n = x.size(), i = 0; i < n; i++) {
                m = x.child(i).accept(this);
                if (i == 0 || max < m)
                    max = m;
            }
            return max + 1;
        }

        @Override
        public Integer visit(NaryFormula x) {
            int max = 0;
            for (int m = 0, n = x.size(), i = 0; i < n; i++) {
                m = x.child(i).accept(this);
                if (i == 0 || max < m)
                    max = m;
            }
            return max + 1;
        }
    };
    Object ans = node.accept(vis);
    if (ans instanceof Integer)
        return ((Integer) ans).intValue();
    else
        return 0;
}