[boost] Re: compare

From: Jan Langer (jan_at_[hidden])
Date: 2003-03-27 14:52:43

David Abrahams wrote:
>>  1) Instead of "operator bool", use the unspecified-bool-type discussed
>>elsewhere on this list; it's safer.
> 
> Yup.

ok, i changed it.

>>  2) I'm not sure that the choice of the name is ideal.  OTOH, I can't think
>>of a better one...
> 
> lexicographic?

i dont bother about the name. if this is better i will change it.

>>  3) I'd like to see a general solution for this problem using real
>>(late-bound) function objects as well, if you know what I mean.  This would
>>be a lot harder, though, so maybe it should be put on a wish-list.  Have you
>>given any thought to this approach?
> 
> 	return compare.less(p1.x, p2.x)
>                   .greater(p1.y, p2.y)
>                   .call(f, p1.z, p2.z);

now this would be:

return compare (p1.x, p2.x, std::less <double> ())
                (p1.y, p2.y, std::greater <double> ())
                (p1.z, p2.z, f);

or nearly the same:

return compare (p1.x, p2.x)
                (p2.y, p1.y)
                (p1.z, p2.z, f);

if the name lexicographic is ok, i will put it in the sandbox. i assume 
the directory utility is the correct place.
jan

-- 
jan langer ... jan_at_[hidden]
"pi ist genau drei"