Den 03-11-2011 09:12, Sergey Voropaev skrev:
Jeffrey Lee Hellrung, Jr.<jeffrey.hellrung<at> gmail.com> writes:
This came up just recently, e.g.,
Sorry, I miss it. Good discussion. And now we have my example with compilation error.
I think the end result was an agreement that
typedef typename boost::make_unsigned< difference_type>::type size_type
would be a valid definition of size_type, so the only argument against making the change that I can see is breaking existing code (probably unlikely...?) and...inertia.
Well, its /not/ unlikely that it will break code.
I did not find authors of "Range" in the discussion. I am afraid your fix will be missed. It is good idea to write formal bug. Can you do it?
I think the most obvious reason we (probabl me) did it like that is that iterator traits have no notion of unsigned types. The above make_signed<> thing could work, but still it will break code. The min() example that fails to compile is tricky. Even if we make it unsigned, size_types may differ (e.g. a 32 bit unsigned int and a 64 bit size_t). One could change min/max to use mpl::identity<T>::type to avoid a second conflicting type deduction, but then you get a warning inside min/max instead. In the end this means that you might as well make the conversion up-front, in your call to min/max. -Thorsten