[boost] Re: Filesystem: create_directories

From: Vladimir Prus (ghost_at_[hidden])
Date: 2003-08-04 01:14:15

David Abrahams wrote:

> The documentation for create_directories makes no sense.  It says
> only:
> 
>     void create_directories( const path & ph );
> 
>     Precondition: ph.empty() ||
>     forall p: p == ph || is_parent(p, ph): is_directory(p) || !exists( p )
> 
>     Postcondition: exists(ph) && is_directory(ph)
> 
> It looks as though this is the same as create_directory, but has a
> weird precondition.  

Sure. It has the (almost) the same postcondition, but has waeker
precondition: the parent directories are not required to exist.

> I swear I was *completely* baffled by its
> purpose until I looked at the header file.

I'd say that pre/post conditions are just correct. Maybe more docs can be
added.

> The comment in the header file describes it pretty well, though.

Ehm... only postcondition there is not correct: is_empty(ph) is not
guaranteed.

- Volodya