On 16-May-08, at 5:01 PM, Craig Latta wrote:

>     Yes. As far as using streams as an example, I never understood  
> why support for write-only streams was ever needed. What's wrong  
> with just assuming all streams are readable? Then this classic  
> dilemma just goes away. It seems to me that whoever wrote the first  
> internal streams implementation for Smalltalk simply got that part  
> wrong, and no one questioned it for a long time. I wouldn't make  
> this a primary motivating example for traits (hopefully there's a  
> better one).

Heh - I've long had nearly the opposite question: Why was support for  
read-write streams ever needed? I can't recall *ever* using it in my  
own code, nor encountering it in anyone else's.

The one exception, of course, is SocketStream, and I think it proves  
the rule. I've had to dig into that code to implement a missing  
feature, and let me tell you... it's complicated. I'd much rather have  
seen clients use two separate streams, or even wrap them in a  
DuplexStream if having a single object is that important.

Colin