Lss // <
	Leq // <=
	Gtr // >
	Geq // >=

	// precAdd
	Add // +
	Sub // -
	Or  // |
	Xor // ^

	// precMul
	Mul    // *
	Div    // /
	Rem    // %
	And    // &
	AndNot // &^
	Shl    // <<
	Shr    // >>
)

// Operator precedences
const (
	_ = iota
	precOrOr
	precAndAnd
	precCmp
	precAdd
	precMul

		y.SetString(test.y, 0)

		testBitFun(t, "and", (*Int).And, x, y, test.and)
		testBitFunSelf(t, "and", (*Int).And, x, y, test.and)
		testBitFun(t, "andNot", (*Int).AndNot, x, y, test.andNot)
		testBitFunSelf(t, "andNot", (*Int).AndNot, x, y, test.andNot)
		testBitFun(t, "or", (*Int).Or, x, y, test.or)
		testBitFunSelf(t, "or", (*Int).Or, x, y, test.or)
		testBitFun(t, "xor", (*Int).Xor, x, y, test.xor)

	binop{"|", func(x, y *big.Int) *big.Int { return new(big.Int).Or(x, y) }},
	binop{"^", func(x, y *big.Int) *big.Int { return new(big.Int).Xor(x, y) }},
	binop{"&^", func(x, y *big.Int) *big.Int { return new(big.Int).AndNot(x, y) }},
}

type unop struct {
	name string
	eval func(x *big.Int) *big.Int
}

var unops = []unop{
	unop{"+", func(x *big.Int) *big.Int { return new(big.Int).Set(x) }},

	if x.neg {
		x, y = y, x // & is symmetric
	}

	// x & (-y) == x & ^(y-1) == x &^ (y-1)
	y1 := nat(nil).sub(y.abs, natOne)
	z.abs = z.abs.andNot(x.abs, y1)
	z.neg = false
	return z
}

// AndNot sets z = x &^ y and returns z.
func (z *Int) AndNot(x, y *Int) *Int {
	if x.neg == y.neg {
		if x.neg {
			// (-x) &^ (-y) == ^(x-1) &^ ^(y-1) == ^(x-1) & (y-1) == (y-1) &^ (x-1)

	{_Operator, "^", Xor, precAdd},

	{_Star, "*", Mul, precMul},
	{_Operator, "/", Div, precMul},
	{_Operator, "%", Rem, precMul},
	{_Operator, "&", And, precMul},
	{_Operator, "&^", AndNot, precMul},
	{_Operator, "<<", Shl, precMul},
	{_Operator, ">>", Shr, precMul},

	// assignment operations
	{_AssignOp, "+=", Add, precAdd},
	{_AssignOp, "-=", Sub, precAdd},
	{_AssignOp, "|=", Or, precAdd},

	syntax.Add: ir.OADD,
	syntax.Sub: ir.OSUB,
	syntax.Or:  ir.OOR,
	syntax.Xor: ir.OXOR,

	syntax.Mul:    ir.OMUL,
	syntax.Div:    ir.ODIV,
	syntax.Rem:    ir.OMOD,
	syntax.And:    ir.OAND,
	syntax.AndNot: ir.OANDNOT,
	syntax.Shl:    ir.OLSH,
	syntax.Shr:    ir.ORSH,
}

// error is called concurrently if files are parsed concurrently.
func (p *noder) error(err error) {
	p.err <- err.(syntax.Error)
}

                }
            }
            if (any.cardinality() > 0 && any.cardinality() != candidateCount) {
                // there is at least one candidate which does NOT provide this attribute
                remaining.andNot(any);
                if (remaining.cardinality() == 0) {
                    // there are no left candidate, do not bother checking other attributes
                    break;
                }
            }

			c.Quo(a, b)
		case token.REM:
			c.Rem(a, b)
		case token.AND:
			c.And(a, b)
		case token.OR:
			c.Or(a, b)
		case token.XOR:
			c.Xor(a, b)
		case token.AND_NOT:
			c.AndNot(a, b)
		default:
			goto Error
		}
		return makeInt(c)

	case ratVal:
		a := x.val
		b := y.(ratVal).val
		c := newRat()
		switch op {
		case token.ADD:

	syntax.Sub: token.SUB,
	syntax.Or:  token.OR,
	syntax.Xor: token.XOR,

	syntax.Mul:    token.MUL,
	syntax.Div:    token.QUO,
	syntax.Rem:    token.REM,
	syntax.And:    token.AND,
	syntax.AndNot: token.AND_NOT,
	syntax.Shl:    token.SHL,
	syntax.Shr:    token.SHR,

	w := (n + _W - 1) / _W
	if uint(len(x)) < w {
		return z.set(x)
	}
	z = z.make(int(w))
	copy(z, x)
	if n%_W != 0 {
		z[len(z)-1] &= 1<<(n%_W) - 1
	}
	return z.norm()
}

func (z nat) andNot(x, y nat) nat {
	m := len(x)
	n := len(y)
	if n > m {
		n = m
	}
	// m >= n

	z = z.make(m)
	for i := 0; i < n; i++ {
		z[i] = x[i] &^ y[i]
	}
	copy(z[n:m], x[n:m])