Weirdness with numeric_limits in new special functions

[Paolo Carlini]

Hi Ed,

> I started working on this but then work flared up bug time.
>
> I think I can return to this a week from now or maybe during this week.

Ok, great.

> I also remembered that we use these template functions that promote 
> the types of all the arguments according to the rules set forth in the 
> standard and in TR1.  One of which is that if an integer is supplied 
> in a slot expecting some floating point type then the integer is 
> promoted to double and the appropriate overload is called.  These 
> functions are in common.h.  I think this sufficiently blocks calling 
> with integral _Tp.

In my opinion, this is a much less urgent issue: eventually, in C++0x, 
concepts will make sure templates are instantiated for a restricted set 
of types. In fact, we could also use now enable_if  here and in many 
other places too, but, in my opinion, we are way to late given that 
C++0x is around the corner. Thus, if you are short of time (we always 
are ;) I would say, let's make sure the behavior of the various 
functions is 100% correct and consistent when instantiated for the 
correct types and let's document the types of the arguments in comments.

Thanks,
Paolo.