🚀 go-pugleaf

R Shapiro wrote:
> 
> I'd like to use the formal argument to a template as the qualifier of a
> qualified typename within the template. This doesn't work in CodeWarrior
> 8, it does work in VC++ 4.0, and I can't tell from ARM whether or not it
> *should* work.
> 
> Here's a more specific example:
> 
> template <class OBJECT>
> class OrderedCollection {
>    typedef void (OBJECT::*memberMapper)(void);
> .
> .
> .
> };
> 
> I would like the typedef 'memberMapper' to refer to pointers to member
> functions (of no arguments and returning no value) of whatever class is
> specified in a given instantiation of the template.
> 
> For instance, if X and Y are classes, I would expect memberMapper in
> OrderedCollection<X> to be:
> 
>   void (X::*memberMapper)(void)
> 
> and memberMapper in OrderedCollection<Y> to be:
> 
>    void (Y::*memberMapper)(void)
> 
> Should this work or not? If not, why not? If so -- this is a bug in CW8.
> 
> --
> rs/rshapiro@bbn.com

I have in my code something like this ...

typedef double (INTERPOLATE_DOS::*TInterpolateFunction)(double);

where INTERPOLATE_DOS is a parameter to the template.

However, I would not be that surprised if CodeWarrior doesn't
work with it. I have a little anecdote. I started trying
to use pointers to member functions of a parametrized class
about 3 years ago. At the time few compilers really had templates
working very well. With a little snippet of code I could break
many compilers. I can still use this to break certain
compilers in certain instances (where the pointer to member function
is to an overloaded function). I have not used CodeWarrior. So
I can't really comment on your question directly. I know that
for most compilers the above DOES work. But I have had the technique
actually cause the SGI compiler to crash, as well as evoke
all kinds of wacky error messages from cfront, and g++, and Borland
C++ 4.5.

Hope that helps.


Andrew
-- 
Andrew Datars	(datars@tiger.physics.utoronto.ca)
Quantum Transport/General Computer Helper		     phone:(416)978-6185
Dept. of Physics, Univ. of Toronto			     fax:  (416)978-2537