Re: template, cast, and operator
On 1/7/2013 1:29 PM, thomas.grund@mail.com wrote:
the following does not compile due to problems with the + operator. The same thing works without templates. How can I achive this?
Thanks a lot,
Thomas
template <typename T = double> class CVariable {
};
template <typename T = double> class CSymbolic {
public:
CSymbolic(CVariable<T>){}
CSymbolic(){}
};
template <typename T> CSymbolic<T> operator+(CSymbolic<T> a1, CSymbolic<T> a2) {
return CSymbolic();
}
int main() {
CVariable<> x, y;
CSymbolic<> f1 = x+y; // problem here
}
What are you trying to achieve? The problem is simple: there is no
operator+ defined for operands of type CVariable<double>. The compiler
is unable to use the operator+ that you defined for CSymbolic<> because
when trying to figure out the type T to instantiate your operator+
*template*, it cannot (shall not) consider conversions.
V
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