[dev] WebDAV package v0.1

[Evert Pot]

> [snip]
> That sounds like a clean approach to me. OTOH we still need similar  
> functionality for internal browsing, but it doesn't make sense to  
> use objects extending Sabre_DAV classes for that purpose.
> Does Sabre require those objects to extend the Sabre classes, or is  
> it sufficient to implement a certain object API?

You can actually implement the interfaces (Sabre_DAV_INode, IFile,  
IDirectory).
The classes are there, because all the methods are already implemented  
to throw a 'Permission denied' by default, which results in less code.

To find out if an object supports for example directory-like  
functinality, just the interfaces are checked. As an alternative I had  
been thinking about using duck-typing, but I ended up preferring  
interfaces, because it forces developers to be more strict.