Ejemplo n.º 1
0
func (this *NNF) VisitFunction(expr expression.Function) (interface{}, error) {
	var exp expression.Expression = expr

	switch expr := expr.(type) {
	case *expression.IsBoolean:
		exp = expression.NewLE(expr.Operand(), expression.TRUE_EXPR)
	case *expression.IsNumber:
		exp = expression.NewAnd(
			expression.NewGT(expr.Operand(), expression.TRUE_EXPR),
			expression.NewLT(expr.Operand(), expression.EMPTY_STRING_EXPR))
	case *expression.IsString:
		exp = expression.NewAnd(
			expression.NewGE(expr.Operand(), expression.EMPTY_STRING_EXPR),
			expression.NewLT(expr.Operand(), expression.EMPTY_ARRAY_EXPR))
	case *expression.IsArray:
		exp = expression.NewAnd(
			expression.NewGE(expr.Operand(), expression.EMPTY_ARRAY_EXPR),
			expression.NewLT(expr.Operand(), _EMPTY_OBJECT_EXPR))
	case *expression.IsObject:
		// Not equivalent to IS OBJECT. Includes BINARY values.
		exp = expression.NewGE(expr.Operand(), _EMPTY_OBJECT_EXPR)
	}

	return exp, exp.MapChildren(this)
}
Ejemplo n.º 2
0
func (this *NNF) VisitBetween(expr *expression.Between) (interface{}, error) {
	err := expr.MapChildren(this)
	if err != nil {
		return nil, err
	}

	return expression.NewAnd(expression.NewGE(expr.First(), expr.Second()),
		expression.NewLE(expr.First(), expr.Third())), nil
}