[boost] Re: yield statement proposal

From: Daniel James (daniel_at_[hidden])
Date: 2005-06-03 03:33:39

Jonathan Turkanis wrote:

> I remember Daniel James had written a coroutine library. Here's the message:
> http://lists.boost.org/boost/2005/01/18687.php. The code is available here, but
> doesn't appear to be well documented:
> ttp://myweb.tiscali.co.uk/calamity/code/coroutines.tar.gz.

It's also a mess and very, very ugly :(. But it does work. I was really 
just experimenting with how far I could push the idea. I was thinking of 
trying to simplify it a bit but never got round to it as I didn't have 
any need for this myself. One thing I was considering was making use of 
phoenix's closures, although that might have ended up being quite verbose.

But it wouldn't be to hard to add recursion to something like Maksym's 
version which would make it a lot more powerful. And I'm not sure why he 
needs 'YIELD_FOR' and 'YIELD_IF'. I think it could quite easily be 
written so that his example would be:

class simple_generator
{
public:
     YIELD_BEGIN_WITH_CTOR( simple_generator, int )
         for( i = 1, i < 4, ++i ) {
             for( j = 1, j < 4, ++j ) {
                 YIELD_RETURN( i * j )
             }
         }
     YIELD_END
private:
     int i;
     int j;
};