Re: [boost] function.hpp: some ideas

From: jk_at_[hidden]
Date: 2001-05-07 04:47:42

4 May 2001 18:53:23 +0400 Douglas Gregor ÎÁÐÉÓÁÌ:
>I think most of us would use NULL if it were truly available, but 
>unfortunately that isn't going to happen any time soon. So instead we use 
>'0', which is only really meaningful because we read it as NULL (or we came 
>from a C backround where typing is willy-nilly). One resolution for this is 
>to have a 'nil' that has its own specific type and a slightly different 
>meaning. Instead of NULL or 0 meaning 'pointing to nothing', nil would mean 
>'possessing no value' or 'possessing an unusable value'.

boost::nil_t would be useful, when someone will decide to implement it:

        extern boost::nil_t nil;
        <...> operator=(boost::nil_t);

>I'd advocate using 'nil' instead of 0 or NULL because it conveys more 
>information than 0 and is more portable than NULL. Additionally the 
>difference in meaning allows it to apply to a greater variety of situations.

-- 
jk