Re: C2275 compiler error under VS C/C++ 6.0

From:
"Doug Harrison [MVP]" <dsh@mvps.org>
Newsgroups:
microsoft.public.vc.language
Date:
Tue, 18 Dec 2007 00:45:29 -0600
Message-ID:
<tjqem39247a2o5o903lqdhtgv1l82be9cu@4ax.com>
On Tue, 18 Dec 2007 00:35:17 -0500, Pops <notreal@placebo.com> wrote:

I'm wondering if a C/C++ guru can assist me with this. The code below
is part of SDK example that compiles under VS 2005, but I am pulling out
parts that I need for my VS 6.0 application and I'm getting the
compiling error:

  C2275: 'File' : illegal use of this type as an expression

at the line indicated below: I stripped it down to the following:

template <class T>
class XMLCollection {
public:
};

struct File {
};

class ReadCollection {
private:
   template <class T>
   const XMLCollection<T> getCollection() const {
      return XMLCollection<T>();
   }
public:
   typedef XMLCollection<File> FileList;

   const FileList excludeFiles() const {
      return getCollection<File>(); //<<< C2275 compiler error
   }
};

What changes I need to make this make this compile under VS C/C++ 6.0?


VC6 has very spotty member template support, and there is no reason for
that function to be a non-static member. You need to make that member
function a non-static member or non-member, but then you're subject to the
VC6 (and 7.0?) bug affecting template parameters that aren't represented in
the function parameter list; the solution to that is to write the function
as:

template <class T>
const XMLCollection<T>
getCollection(T* = 0) const
{
   return XMLCollection<T>();
}

Perhaps the best solution is to get rid of this superfluous function and
just write XMLColllection<T>() wherever you would call it. I mean, the
function hardly saves you anything! But wait, you actually have a typedef,
so this should be written:

const FileList
excludeFiles() const
{
   return FileList();
}

Thanks in advance.


You're retroactively welcome?

--
Doug Harrison
Visual C++ MVP

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