Hello, i am Andrés, i am new in the boost world and i have an idea to
boost.any.
With the actual boost::any i can't do this:
boost::any any_var;
int i;
any_var = 10;
i = 1 + any_var;
double d;
// d = 1.0 + any_var; // throw: bad_any_cast, because any_var is int
any_var = 10.0;
d = 1.0 + any_var - 3.0; // now any_var is double
because are incompatible types. To solve this problem, we need add the
casting operator and add overload the global operators.
I wrote the code and actually have the global operators overloaded +, -, *,
/, %.
I don't know how write code to Boost, for this reason maybe has errors.
namespase boost {
class any {
//....
public:
// casting operators
template <class ValueType>
operator ValueType
() const
{
return boost::any_cast<ValueType>(*this);
}
template <class ValueType>
operator ValueType
()
{
return boost::any_cast<ValueType>(*this);
}
// arithmetic operators
template <typename ValueType>
ValueType operator+
(const ValueType& t1) const
{
return (ValueType)(*this) + t1;
}
template <typename ValueType>
ValueType operator-
(const ValueType& t1) const
{
return (ValueType)(*this) - t1;
}
template <typename ValueType>
ValueType operator*
(const ValueType& t1) const
{
return (ValueType)(*this) * t1;
}
template <typename ValueType>
ValueType operator/
(const ValueType& t1) const
{
return (ValueType)(*this) / t1;
}
template <typename ValueType>
ValueType operator%
(const ValueType& t1) const
{
return (ValueType)(*this) % t1;
}
//...
} // End any
//...
// Global operators
template <class ValueType>
ValueType operator+
(ValueType t1, boost::any t2)
{
return t1 + (ValueType)(t2);
}
template <class ValueType>
ValueType operator-
(ValueType t1, boost::any t2)
{
return t1 - (ValueType)(t2);
}
template <class ValueType>
ValueType operator*
(ValueType t1, boost::any t2)
{
return t1 * (ValueType)(t2);
}
template <class ValueType>
ValueType operator/
(ValueType t1, boost::any t2)
{
return t1 - (ValueType)(t2);
}
template <class ValueType>
ValueType operator%
(ValueType t1, boost::any t2)
{
return t1 % (ValueType)(t2);
}
}
If you like it or not, please tell me.
Excuse my English
