UnaryOp(const std::string &name, Expression *arg)
Constructor.
A base class for unary functions.
UnaryOp & operator=(const UnaryOp &rhs)
UnaryFunction & operator=(const UnaryFunction &rhs)
A base class for unary operators.
A base class for unary operators.
This is an abstract class that models a query expression.
Expression * clone() const
It creates a new copy of this expression.