[cfe-dev] Again on Elaborated, QualifiedName and DependentName type nodes.

[Douglas Gregor]

On May 10, 2010, at 10:45 AM, Enea Zaffanella wrote:

> Hello.
> 
> We were reconsidering the design of C++ AST nodes
>   ElaboratedType
>   QualifiedNameType
>   DependentNameType
> In our opinion, the design of class DependentNameType, bringing
> together the elaborated keyword and the name qualification, is actually 
> good. In contrast, the distinction between ElaboratedType and
> QualifiedNameType seems somewhat artificial.
> Would it be acceptable to  collapse these two nodes in a single one, 
> bringing together the corresponding info, similarly to DependentNameType?

Yes, I think that's a great idea. DependentNameType ended up much cleaner than what we had previously, and I'd love to see this same approach applied to ElaboratedType/QualifiedNameType.

> If so, then we would try and propose an alternative patch wrt the one 
> submitted here:
> http://lists.cs.uiuc.edu/pipermail/cfe-commits/Week-of-Mon-20100503/030031.html
> 
> After that is put straight, we would like to consider the addition of 
> appropriate typeloc info to the corresponding classes
>   ElaboartedTypeLoc
>   QualifiedNameTypeLoc
>   DependentNameTypeLoc
> Again, we conjecture that collapsing Elaborated and QualifiedName would 
> allow for a cleaner design.

I think so, too.

> However, in this case we have another doubt.
> An elaborated typeloc should contain syntactic info for the underlying 
> tag type node. Should we add a TypeSourceInfo* to the corresponding 
> LocInfo class (as done for TypeOfTypeLoc), or should we have the 
> ElaboratedTypeLoc have an _inner_ typeloc (as done for pointer and array 
> typelocs)?


I'd prefer an inner typeloc, as with pointers and arrays.

	- Doug