🚀 go-pugleaf

In article <30753E6F@Toronto.LinkAge.com>,
   Harvey Rook <harveyr@LinkAge.com> wrote:
>What does the standard say about templates and inline functions that are 
>never used? Do they have to contain completly valid code? Or can they be 
>ignored? Which compiler is right?

Template code that is never called should not be generated -- whether inline 
or out-of-line.  Not only does this mean that classes like the one you showed 
(one which is never instantiated) should never get code generated, but even 
classes which are instantiated should only have those templated members 
instantiated that are actually used.  In other words, you can have a class 
with some function that contains illegal code (either always illegal, or 
illegal to instantiate for a particular type), and the compiler should not 
generate the code if it is not called.  Incidentally, this feature is quite 
useful... not just because is saves dead code, but because it gives you some 
flexibility with a template's type restraints if you don't plan to use all 
features of the template.

As you've noticed, though, compilers are always playing catchup with the draft 
and not all have even basic templates solidly implemented yet.  For example, I 
would be surprised if Visual C++ supported the above requirement (from all 
that I've heard their template code is still weak... won't run a complete STL 
implementation, for example).

Herb


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