Re: Templating classes

From:
 MathStuf <MathStuf@gmail.com>
Newsgroups:
comp.lang.c++
Date:
Fri, 01 Jun 2007 21:38:58 -0000
Message-ID:
<1180733938.412548.36970@q75g2000hsh.googlegroups.com>
On Jun 1, 5:11 pm, red floyd <no.s...@here.dude> wrote:

MathStuf wrote:

[redacted]

Hmm...guess I should have looked exactly where it was getting mixed up
there. It's in the following code:

template<class T> class Matrix : public MatrixBase<T>
{
   public:
      Matrix()
      {
         width = 0;
         height = 0;
         matrix.clear();
      }
      // More methods
};


Note that since width and height are members of MatrixBase<>, it's
probably better to let MatrixBase set them. If you need something other
than what MatrixBase has set as the "default", MatrixBase should have a
constructor with width and height parameters.


Alright, but I still have problems with their availability. I have
GetWidth() and GetHeight() methods in MatrixBase<>, but when i go to
call it, the compiler complains about it.

\Matrix.h:161: error: there are no arguments to `GetHeight' that
depend on a template parameter, so a declaration of `GetHeight' must
be available

I'm confused since MatrixBase<T> is inherited as public, and protected
members should be available (as well as public ones such as
GetHeight() and GetWidth()). I have other classes (non-template
though) where an id is inherited from the base class (public
inheritance of a protected variable) and straight calls to the id
works. Do templates mess with inheritance at all? I don't think they
would, but that's what it would seem is happening here.

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