Base classes declaration under DUChains

[David Nolden]

Am Freitag 13 März 2009 21:46:03 schrieb Lior Mualem:
> Hi,
> I'm trying to display a list of base classes within the class browser and I
> see that the base classes list is Cpp specific - in Cpp::ClassDeclaration
> thus it exists only within the KDevelop project and not under the
> kdevplatform project (which is where the class browser should be).
There is a slight duplication in this regard. You can also get to the base 
classes through the context structure:
Declaration* declaration = Declaration of a class
foreach(DUContext::Import import, declaration->internalContext()-
>importedParentContext())
 if(import.context()->kind() == DUContext::Class)
	then import.context()->owner() is the declaration of a base-class of 
declaration

Notice that you always have to do a null-pointer check, for all the pointers 
treated in that code.

> Is there a reason why a list of base classes shouldn't reside within
> something that's defined in kdevplatform (atleast an interface class)?
I think we were thinking about moving Cpp::ClassDeclaration to kdevplatform, 
but haven't come to it yet.

> I didn't really get to the bottom of understanding the difference between
> AbstractType hierarchy and the Declaration hierarchy so I might be
> completly wrong here but bottom line, I just want to get a the list of base
> classes for a specific class declaration/type. Any help in that direction
> would be appreciated.
Types are completely separate of declarations, and they are the shared meta-
data that describes the logical types in a C++ sense, without being bound to a 
context. The most important thing is that there is never a direct reference 
from a type to a declaration, and there may be many declarations using a 
single type. Even the same type may be declared in multiple places(For example 
when headers were installed, but he source is parsed as well)

> Thanks.
>
> P.S: Is there developer documentation that explains the idea behind the
> different classes and their relations with regards to DUChains?
I think Hamish Rodda has written some documentation, I don't know where it can 
be found though.

So how far have you come with the class-browser? At some point I might peek at 
what you've done. The most important thing is that it should be fast. You 
should remember that whenever you call 
KDevelop::IndexedDeclaration::declaration(), it may mean a complete file has 
to be loaded from disk. For that reason, the actual duchain declarations or 
contexts should only be used for displaying detailed information that is 
actually visible on the screen. All other content of the class-browser should 
use the simple representation from KDevelop::CodeModel(It is maybe a bit too 
simple, but with some tricks, it can be used to build a hierarchy)

Greetings, David