Re: [boost] [serialization] facets for non-finite numbers

From: Johan Råde (rade_at_[hidden])
Date: 2006-08-02 09:39:55

Paul A Bristow wrote:
> Johan Råde wrote:
> |  Paul A. Bristow wrote:> |  
> |  > Surely C99 signbit tests the sign bit?

> |  You are right, but our goals are different. You are working on a 
> |  proposal to the C++ standardization committee. I writing code that 
> |  should work with existing C++ compilers and std lib 
> |  implementations. So I can not assume that the C99 signbit macro is
> present.
> 
> OK, so why not write - or get someone else to write ;-)
> a C++ is_negative function,
> and use the signbit macro if available,
> or make up your own bit test if not?
> 
> There are a few variations with type, endianness and compiler, of course,
> but not TOO many?

I'm not going to do it.
I don't need the sign bit in Nan (and 0),
and I don't want to dig into the binary representation
of floating point numbers on different platforms.

If anyone needs it, let him write it.
If he does, I will add it to my code.

--Johan Råde