Java Code Examples for kodkod.ast.NaryExpression#size()

/**
 * Calls lookup(expr) and returns the cached value, if any. If a replacement has
 * not been cached, visits the expr's children. If nothing changes, the argument
 * is cached and returned, otherwise a replacement expr is cached and returned.
 *
 * @return { e: Expression | e.op = expr.op && #e.children = #expr.children &&
 *         all i: [0..expr.children) | e.child(i) =
 *         expr.child(i).accept(delegate) }
 */
@Override
public Expression visit(NaryExpression expr) {
    Expression ret = lookup(expr);
    if (ret != null)
        return ret;

    final Expression[] visited = new Expression[expr.size()];
    boolean allSame = true;
    for (int i = 0; i < visited.length; i++) {
        final Expression child = expr.child(i);
        visited[i] = child.accept(delegate);
        allSame = allSame && visited[i] == child;
    }

    ret = allSame ? expr : Expression.compose(expr.op(), visited);
    return cache(expr, ret);
}
 

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

/**
 * Calls lookup(expr) and returns the cached value, if any.  
 * If a translation has not been cached, translates the expression,
 * calls cache(...) on it and returns it.
 * @return let t = lookup(expr) | some t => t, 
 *      let op = (expr.op).(UNION->or + INTERSECTION->and + DIFFERENCE->difference + OVERRIDE->override + JOIN->dot + PRODUCT->cross) | 
 *       cache(expr, op(expr.left.accept(this), expr.right.accept(this)))
 */
public BooleanMatrix visit(NaryExpression expr) {
	BooleanMatrix ret = lookup(expr);
	if (ret!=null) return ret;

	final ExprOperator op = expr.op();
	final BooleanMatrix first = expr.child(0).accept(this);		
	final BooleanMatrix[] rest = new BooleanMatrix[expr.size()-1];
	for(int i = 0; i < rest.length; i++) { 	rest[i] = expr.child(i+1).accept(this); }
	
	switch(op) {
	case UNION        	: ret = first.or(rest); break;
	case INTERSECTION	: ret = first.and(rest); break;
	case OVERRIDE 		: ret = first.override(rest); break;
	case PRODUCT		: ret = first.cross(rest); break;
	default : 
		throw new IllegalArgumentException("Unknown associative operator: " + op);
	}

	return cache(expr, ret);
}
 

/** @return true if e is (a product of) Expression.NONE*/
private boolean isEmpty(Expression e) { 
	if (e==Expression.NONE) return true;
	else if (e instanceof BinaryExpression) { 
		final BinaryExpression b = (BinaryExpression) e;
		return b.op()==ExprOperator.PRODUCT && isEmpty(b.left()) && isEmpty(b.right());
	} else if (e instanceof NaryExpression) { 
		final NaryExpression n = (NaryExpression) e;
		if (n.op()==ExprOperator.PRODUCT) { 
			for(int i = 0, max = n.size(); i < max; i++) { 
				if (!isEmpty(n.child(i))) return false;
			}
			return true;
		}
	}
	return false;
}
 

public Expression visit(NaryExpression expr) { 
	Expression ret = lookup(expr);
	if (ret!=null) return ret;
	
	final ExprOperator op = expr.op();
	
	final List<Expression> children = simplify(op, visitAll(expr));
	final int size = children.size();
	switch(size) { 
	case 0 : return cache(expr, empty(expr.arity()));
	case 1 : return cache(expr, children.get(0));
	default :
		ret = expr.size()==size && allSame(expr,children) ? expr : Expression.compose(op, children);
		return cache(expr,ret);
	}	
}
 

/**
 * Calls lookup(expr) and returns the cached value, if any. If a translation has
 * not been cached, translates the expression, calls cache(...) on it and
 * returns it.
 *
 * @return let t = lookup(expr) | some t => t, let op = (expr.op).(UNION->or +
 *         INTERSECTION->and + DIFFERENCE->difference + OVERRIDE->override +
 *         JOIN->dot + PRODUCT->cross) | cache(expr, op(expr.left.accept(this),
 *         expr.right.accept(this)))
 */
@Override
public BooleanMatrix visit(NaryExpression expr) {
    BooleanMatrix ret = lookup(expr);
    if (ret != null)
        return ret;

    final ExprOperator op = expr.op();
    final BooleanMatrix first = expr.child(0).accept(this);
    final BooleanMatrix[] rest = new BooleanMatrix[expr.size() - 1];
    for (int i = 0; i < rest.length; i++) {
        rest[i] = expr.child(i + 1).accept(this);
    }

    switch (op) {
        case UNION :
            ret = first.or(rest);
            break;
        case INTERSECTION :
            ret = first.and(rest);
            break;
        case OVERRIDE :
            ret = first.override(rest);
            break;
        case PRODUCT :
            ret = first.cross(rest);
            break;
        default :
            throw new IllegalArgumentException("Unknown associative operator: " + op);
    }

    return cache(expr, ret);
}
 

/**
 * @ensures appends the tokenization of the given node to this.tokens
 */
@Override
public void visit(NaryExpression node) {
    final ExprOperator op = node.op();
    visitChild(node.child(0), parenthesize(op, node.child(0)));
    for (int i = 1, size = node.size(); i < size; i++) {
        infix(op);
        visitChild(node.child(i), parenthesize(op, node.child(i)));
    }
}
 

/** {@inheritDoc} */
@Override
public void visit(NaryExpression x) {
    String newname = makename(x);
    if (newname == null)
        return;
    String[] list = new String[x.size()];
    for (int i = 0; i < list.length; i++)
        list[i] = make(x.child(i));
    file.printf("Expression %s=Expression.compose(ExprOperator.", newname);
    switch (x.op()) {
        case INTERSECTION :
            file.print("INTERSECTION");
            break;
        case OVERRIDE :
            file.print("OVERRIDE");
            break;
        case PRODUCT :
            file.print("PRODUCT");
            break;
        case UNION :
            file.print("UNION");
            break;
        default :
            throw new RuntimeException("Unknown kodkod operator \"" + x.op() + "\" encountered");
    }
    for (int i = 0; i < list.length; i++)
        file.printf(", %s", list[i]);
    file.printf(");%n");
}
 

/** @ensures appends the tokenization of the given node to this.tokens */
public void visit(NaryExpression node) {
	final ExprOperator op = node.op();
	visitChild(node.child(0), parenthesize(op, node.child(0)));
	for(int i = 1, size = node.size(); i < size; i++) {
		infix(op);
		visitChild(node.child(i), parenthesize(op, node.child(i)));
	}
}
 

/** @effects appends the tokenization of the given node to this.tokens */
public void visit(NaryExpression node) {
	if (displayed(node)) return;
	final boolean oldTop = notTop();
	final ExprOperator op = node.op();
	visitChild(node.child(0), parenthesize(op, node.child(0)));
	for(int i = 1, size = node.size(); i < size; i++) {
		infix(op);
		visitChild(node.child(i), parenthesize(op, node.child(i)));
	}
	top = oldTop;
}