Library Typedefs are fundamentally broken

[Adam D. Ruppe via Digitalmars-d]

On Monday, 22 September 2014 at 17:21:50 UTC, Andrei Alexandrescu 
wrote:
> I find the requirement for the cookie perfect.

There is one thing I like about it and wish was available 
elsewhere: two modules can define the same type for 
interoperability without needing to import each other.

My simpledisplay.d and image.d modules both used to be 
standalone. Both defined struct Color {}. Identical layout. When 
I added optional integration, these two structs clashed.

The solution was to introduce module color, which held that 
struct. But now both modules require that import. Works fine but 
I think it would have been great if I could have kept the two 
separate definitions and just told the compiler it's ok, these 
two types are indeed identically compatible despite coming from 
independent modules.

kinda like pragma(mangle) but for types and preferably less hacky.


Another potential use of this concept would be separate interface 
and implementation files.


But that's all pretty different than the Typedef cookie. I'm just 
saying it because the concept of matching types in different 
modules IS something that I've wanted in the past.