🚀 go-pugleaf

> I believe it is implicit in the semantic descriptions throughout the DWP.
> For functions (member or not), they should only be instantiated if they
> are called. The only exception are virtual functions: they can be 
> instantiated if the class to which they belong is instantiated.
> 
> Classes and member classes should be instantiated only if their size
> or at least part of their layout is needed. If only their name is needed,
> no instantiation should occur.
> 

What about the use of a typedef name from the class.  No size or layout
is needed.   Example:

struct incomplete;

template <class T>
struct allocator {
public :
  typedef T* pointer;
  incomplete i;
};

template <class T>
struct vector {
  allocator<T>::pointer start;
  vector();
};

main()
{
  vector<int> v;
  return 0;
}

Then this should be well-formed.  While specializing vector<int> we have
to determine the member start's type.  We don't need to specialize 
allocator<int> to do that.  So we can use allocator<int>::pointer, and
allocator<anything>::pointer without ever specializing the class.  Is that
the intent?  Is that desirable?

-- 
Mike Rice                                                   Absoft Corporation
mpr@absoft.com                                                  (810) 853-0050

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