Re: nested template class instantiation from template function problems
On Jul 17, 8:29 pm, Jeff Koftinoff <jeff.koftin...@gmail.com> wrote:
I'm certain that I'm doing something wrong here, but I'm not sure how
to do it right.
Here is the code and the errors I get by uncommenting the individual
lines.
Similar errors happen from Comeau's tryitout, so I think this is not a
gcc bug.
template <typename T>
void test2()
{
typedef X<T> Z;
//typedef typename Z::Y<2> Z1; // line 32
//typedef Z::Y<2> Z1; // line 33
//X<T>::Y<2> z1; // line 34
//typename X<T>::Y<2> z1; // line 35
}
t.cpp:32: error: non-template 'Y' used as template
...
t.cpp:33: error: non-template 'Y' used as template
...
t.cpp:34: error: 'z1' was not declared in this scope
...
t.cpp:34: error: dependent-name 'X<T>::Y' is parsed as a non-type, but
Try this set of declarations:
template <typename T>
void test2()
{
typedef X<T> Z;
typedef typename Z::template Y<2> Z1;
typename X<T>::template Y<2> z1;
}
Essentially, the "template" keyword is needed to identify a nested
templates that appears inside of a template (class or function).
Greg
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