8 May
2005
8 May
'05
9:53 p.m.
Beman Dawes wrote:
A hypothetical OS that allows directories to be opened with an ifstream may reasonably answer true to both is_stream(p) and is_directory(p). Or maybe not. :-)
I think not. Dividing the world into non-overlapping categories is much easier:-)
It's only easier until an example comes up that doesn't fit the scheme, so you are forced to invent meta-categories (also known as "hacks" in some category theory circles) such as "other". :-) "Capability bits" are cleaner. Is it openable with ifstream? file_bit. Is it iteratable with directory_iterator? directory_bit. Does it exist? !not_found_bit. When a socket is thrown your way, you just run it by the list and conclude that no bit needs to be set.