Ok, I've got code that looks something like this:
==================================================
template<typename T1, typename T2>
class Base
{
public:
explicit Base(const T1 & t1) { /* ... */ }
};
template<typename T1, typename T2, typename T3>
class Derived : public Base<T1, T2>
{
public:
Derived() : Base(my_t3) { /* ... */ }
private:
T3 my_t3;
};
================================================== ==
GCC 3.3.1 reports the following error:
In constructor `Derived<T1, T2, T3>::Derived()':
error: class `Derived<T1, T2, T3>' does not have any field named
`template<class T1, T2> class Base'
It would seem that GCC interprets my initialization of Base in
Derived's constructor as a field assignment. Is my syntax wrong? Is
there some way to more directly indicate that I'm invoking Base's
constructor?
Thanks,
--Steve (mr************@hotmail.com) 5 7283
mrstephengross wrote: Ok, I've got code that looks something like this:
==================================================
template<typename T1, typename T2> class Base { public: explicit Base(const T1 & t1) { /* ... */ } };
template<typename T1, typename T2, typename T3> class Derived : public Base<T1, T2> { public: Derived() : Base(my_t3) { /* ... */ }
Has to be
Derived() : Base<T1,T2>(my_t3) { }
or you need to typedef 'Base<T1,T2>' as "Base" before. private: T3 my_t3; };
================================================== ==
GCC 3.3.1 reports the following error:
In constructor `Derived<T1, T2, T3>::Derived()': error: class `Derived<T1, T2, T3>' does not have any field named `template<class T1, T2> class Base'
It would seem that GCC interprets my initialization of Base in Derived's constructor as a field assignment. Is my syntax wrong?
Yes.
Is there some way to more directly indicate that I'm invoking Base's constructor?
See above.
V
Victor Bazarov wrote: mrstephengross wrote: Ok, I've got code that looks something like this:
==================================================
template<typename T1, typename T2> class Base { public: explicit Base(const T1 & t1) { /* ... */ } };
template<typename T1, typename T2, typename T3> class Derived : public Base<T1, T2> { public: Derived() : Base(my_t3) { /* ... */ }
Has to be
Derived() : Base<T1,T2>(my_t3) { }
That's the correct syntax, but isn't there a logic flaw
in the Base() call? The Base() constructor expects a
'T1' parameter, rather than a 'T3' parameter.
[snip]
Regards,
Larry
--
Anti-spam address, change each 'X' to '.' to reply directly.
>That's the correct syntax, but isn't there a logic flaw
in the Base() call? The Base() constructor expects a
'T1' parameter, rather than a 'T3' parameter.
Yeah, you're right... I didn't paste in my example correctly. But the
main issue has been resolved: apparently C++ requires that you
explicitly specify the constructor's template arguments. I had been
using a compiler (KCC) that was more forgiving...
--Steve
mrstephengross wrote: That's the correct syntax, but isn't there a logic flaw in the Base() call? The Base() constructor expects a 'T1' parameter, rather than a 'T3' parameter.
Yeah, you're right... I didn't paste in my example correctly. But the main issue has been resolved: apparently C++ requires that you explicitly specify the constructor's template arguments. I had been using a compiler (KCC) that was more forgiving...
--Steve
"Base<T1, T2>" IS the class name. "Base" is something
entirely different. g++ is merely enforcing the standard.
BTW, you do know that you compile/link C++ code with the GCC
command "g++", NOT with the command "gcc"???
Regards,
Larry
--
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