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

Example 26 with Variable

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

the class Skolemizer method visit.

/**
 * Skolemizes the given formula, if possible, otherwise returns the result of
 * replacing its free variables according to the current replacement
 * environment.
 *
 * @see kodkod.ast.visitor.AbstractReplacer#visit(kodkod.ast.QuantifiedFormula)
 */
@Override
public final Formula visit(QuantifiedFormula qf) {
    Formula ret = lookup(qf);
    if (ret != null)
        return ret;
    final Environment<Expression, Expression> oldRepEnv = repEnv;
    final Quantifier quant = qf.quantifier();
    final Decls decls = qf.decls();
    if (skolemDepth >= 0 && (negated && quant == ALL || !negated && quant == SOME)) {
        // skolemizable
        // formula
        final List<Formula> rangeConstraints = new LinkedList<Formula>();
        final List<Formula> domConstraints = new LinkedList<Formula>();
        for (Decl decl : decls) {
            final Decl skolemDecl = visit(decl);
            Variable skVar = skolemDecl.variable();
            final Relation skolem = Relation.skolem("$" + skVar.name(), nonSkolems.size() + skVar.arity(), skVar, skolemDecl, quant);
            reporter.skolemizing(decl, skolem, nonSkolemsView);
            final Expression skolemExpr = skolemExpr(skolemDecl, skolem);
            final Multiplicity mult = decl.multiplicity();
            rangeConstraints.add(source(skolemExpr.in(skolemDecl.expression()), decl));
            if (mult != Multiplicity.SET) {
                rangeConstraints.add(source(skolemExpr.apply(mult), decl));
            }
            if (!nonSkolems.isEmpty())
                domConstraints.add(source(domainConstraint(skolemDecl, skolem), decl));
            repEnv = repEnv.extend(decl.variable(), decl.expression(), skolemExpr);
        }
        ret = source(Formula.and(rangeConstraints), decls).compose(negated ? IMPLIES : AND, qf.formula().accept(this));
        if (!domConstraints.isEmpty())
            topSkolemConstraints.add(source(Formula.and(domConstraints), decls));
    } else {
        // non-skolemizable formula
        final Decls newDecls = visit(qf.decls());
        if (skolemDepth >= nonSkolems.size() + newDecls.size()) {
            // below
            for (Decl d : newDecls) {
                nonSkolems.add(new DeclInfo(d));
            }
            final Formula domain = qf.domain().accept(this);
            final Formula body = qf.body().accept(this);
            ret = ((newDecls == decls && domain == qf.domain() && body == qf.body()) ? qf : body.quantify(quant, newDecls, domain));
            for (int i = newDecls.size(); i > 0; i--) {
                nonSkolems.remove(nonSkolems.size() - 1);
            }
        } else {
            // can't skolemize below
            final int oldDepth = skolemDepth;
            skolemDepth = -1;
            final Formula domain = qf.domain().accept(this);
            final Formula body = qf.body().accept(this);
            ret = ((newDecls == decls && domain == qf.domain() && body == qf.body()) ? qf : body.quantify(quant, newDecls, domain));
            skolemDepth = oldDepth;
        }
    }
    repEnv = oldRepEnv;
    if (repEnv.isEmpty() && !topSkolemConstraints.isEmpty()) {
        ret = source(Formula.and(topSkolemConstraints), qf).compose(negated ? IMPLIES : AND, ret);
    }
    return source(cache(qf, ret), qf);
}

Example 27 with Variable

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

the class AbstractReplacer method visit.

/**
 * Calls lookup(decl) and returns the cached value, if any. If a replacement has
 * not been cached, visits the declaration's variable and expression. If nothing
 * changes, the argument is cached and returned, otherwise a replacement Decl
 * object is cached and returned.
 *
 * @return { d: Declaration | d.variable = declaration.variable.accept(delegate)
 *         && d.multiplicity = decl.multiplicity && d.expression =
 *         declaration.expression.accept(delegate)
 */
@Override
public Decl visit(Decl decl) {
    Decl ret = lookup(decl);
    if (ret != null)
        return ret;
    final Variable variable = (Variable) decl.variable().accept(delegate);
    final Expression expression = decl.expression().accept(delegate);
    ret = (variable == decl.variable() && expression == decl.expression()) ? decl : variable.declare(decl.multiplicity(), expression);
    return cache(decl, ret);
}

Example 28 with Variable

use of kodkod.ast.Variable 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;
}

Example 29 with Variable

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

the class FileLogger method log.

/**
 * Records the translation of the source of the given transformed formula to the
 * given boolean value in the specified environment.
 *
 * @requires some this.transforms.f
 * @ensures this.records' = this.records + this.transforms.f -> translation ->
 *          freeVariables(f)<:env
 * @throws IllegalArgumentException no this.transforms.f
 * @throws IllegalStateException this log has been closed
 */
@Override
void log(Formula f, BooleanValue v, Environment<BooleanMatrix, Expression> env) {
    if (out == null)
        throw new IllegalStateException();
    final int index = logMap.indexOf(f);
    if (index < 0)
        throw new IllegalArgumentException();
    final Variable[] vars = logMap.get(index);
    try {
        out.writeInt(index);
        out.writeInt(v.label());
        for (Variable var : vars) {
            out.writeInt(env.lookup(var).denseIndices().min());
        }
    } catch (IOException e) {
        throw new RuntimeException(e);
    }
}

Example 30 with Variable

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

the class FreeVariableCollector method visit.

/**
 * Visits the given comprehension, quantified formula, or sum expression. The
 * method returns a set that contains all the free variables in the declarations
 * and the body, minus the variables that are actually bound in the
 * declarations.
 */
@SuppressWarnings("unchecked")
private Set<Variable> visit(Node creator, Decls decls, Node body) {
    Set<Variable> ret = lookup(creator);
    if (ret != null)
        return ret;
    ret = newSet();
    final Set<Variable> boundVars = newSet();
    // computed set and previously bound variables to ret
    for (Decl decl : decls) {
        for (Variable v : visit(decl)) {
            if (!boundVars.contains(v))
                ret.add(v);
        }
        varsInScope.push(decl.variable());
        boundVars.add(decl.variable());
    }
    // add to ret the free variables in the body, minus the bound variables
    for (Variable v : (Set<Variable>) body.accept(this)) {
        if (!boundVars.contains(v))
            ret.add(v);
    }
    // remove the declared variables from the in-scope stack
    for (int i = decls.size(); i > 0; i--) {
        varsInScope.pop();
    }
    return cache(creator, ret);
}