Allison,
Allison Randal wrote:
I've just moved pdd22 out of the clip directory, marking it as ready
for beginning implementation efforts.
Excellent! I've just read through it and like what I'm seeing.
Comments on the pdd are welcomed. A few things worth highlighting:
- I/O layers will be replaced with role composition.
I like the look of this, but if I wanted to go about implementing it I
feel I'm kinda short of what that means implementation wise. I'm happy
enough with flattening composition and all that jazz, but a little extra
guidance on what you're expecting to compose into the object and where
the roles come from would be very helpful to me, and maybe to others who
are considering trying to implement some of this. (I hope the question
makes sense. If not, I'll try and ask it a better way. Well, a different
way at least. :-))
- One question still under discussion is error handling. Should all
errors be exceptions? Integer status codes? More details in the PDD.
I suspect it's cheaper/easier for a compiler to generate code to check a
return value and throw an exception of its own choosing, than it is to
emit code to catch the exception and return the error value.
Thanks,
Jonathan
