Re: Template problem

"Jens Mander" <jens@xxxxxxxxxx> wrote in message
news:OaXCBvRBHHA.1012@xxxxxxxxxxxxxxxxxxxx
The following code generates errors when compiled using VC++ 7.1.
However, gcc 3.2.2 and comeau online have no problems with it. Is
this illegal code or a compiler bug? If it is the latter; was it
fixed in the latest release of VC++? Are there any workarounds for my
version?

Thank you in advance!

====================
template <typename T>
struct Outer
{
template <T value = 0>
struct Inner {};
};

int main ()
{
Outer<int>::Inner<> fail;
}


1. I'm guessing it is a bug.

2. No, it hasn't been fixed.

3. A workaround is to only forward declare the Inner class when you declare
the Outer class, and to add the full declaration of Inner later.

template <typename T>
struct Outer
{
// forward declare
template <T value = 0>
struct Inner;
};

// complete the declaration
template <typename T>
template<T value>
struct Outer<T>::Inner<value>
{};


int main ()
{
Outer<int>::Inner<> fail;
return 0;
}


--
John Carson


.

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