Hello!
I have this template class with a default type (please do not give too
much importance to the actual code, it's just an example, it's not a
useful implementation of anything nor a good example of use of void*):
template <typename Type = void>
class MyClass {
int Var;
Type* Get() {
return((Type*)V ar);
}
void Set(Type* Address) {
Var=(int)Addres s;
}
};
I can declare instances of this class like:
MyClass<int Instance1;
MyClass<shortIn stance2;
MyClass<void Instance3;
etc..
the latter can be written also as:
MyClass<Instanc e3;
and here's finally the question: I'd like to use also this default form:
MyClass Instance3;
which of course will be perfectly equivalent to MyClass<and MyClass<void>
How do I do it? I tried some namespace trick, but not successfully (which
doesn't mean it's not the right way to go, but just that I'm too lame to
successfully bring it to life).
Please note I am using VisualC++ 8.0 (a.k.a. 2005) targeting native x86
code on 32bit Windows and I do NOT care about portability for the specific
case, so any trick that would work with this compiler would be fine++ for
me.
Thank you very much,
Tony 2 2064 to**@donotspamm e.ar wrote:
I have this template class with a default type (please do not give too
much importance to the actual code, it's just an example, it's not a
useful implementation of anything nor a good example of use of void*):
template <typename Type = void>
class MyClass {
int Var;
Type* Get() {
return((Type*)V ar);
}
void Set(Type* Address) {
Var=(int)Addres s;
}
};
I can declare instances of this class like:
MyClass<int Instance1;
MyClass<shortIn stance2;
MyClass<void Instance3;
etc..
the latter can be written also as:
MyClass<Instanc e3;
and here's finally the question: I'd like to use also this default
form: MyClass Instance3;
which of course will be perfectly equivalent to MyClass<and
MyClass<void>
How do I do it? I tried some namespace trick, but not successfully
(which doesn't mean it's not the right way to go, but just that I'm
too lame to successfully bring it to life).
There is no way. A template-id (and that's what "MyClass" is) has
to be followed by the opening angle bracket.
Please note I am using VisualC++ 8.0 (a.k.a. 2005) targeting native
x86 code on 32bit Windows and I do NOT care about portability for the
specific case, so any trick that would work with this compiler would
be fine++ for me.
Then post your compiler-specific inquiry to the newsgroup that deals
with that compiler only: microsoft.publi c.vc.language. We here _do_
care about portability and saying "I don't care" is an insult.
V
--
Please remove capital 'A's when replying by e-mail
I do not respond to top-posted replies, please don't ask to**@donotspamm e.ar wrote:
I have this template class with a default type (please do not give too
much importance to the actual code, it's just an example, it's not a
useful implementation of anything nor a good example of use of void*):
template <typename Type = void>
class MyClass {
int Var;
Type* Get() {
return((Type*)V ar);
}
void Set(Type* Address) {
Var=(int)Addres s;
}
};
I can declare instances of this class like:
MyClass<int Instance1;
MyClass<shortIn stance2;
MyClass<void Instance3;
etc..
the latter can be written also as:
MyClass<Instanc e3;
and here's finally the question: I'd like to use also this default form:
MyClass Instance3;
which of course will be perfectly equivalent to MyClass<and MyClass<void>
How do I do it? I tried some namespace trick, but not successfully (which
doesn't mean it's not the right way to go, but just that I'm too lame to
successfully bring it to life).
namespace detail {
template<typena me T = void>
class Foo {};
}
typedef detail::Foo<Foo ;
Best regards,
Tom This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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