[lmm]

What do you mean by greenlets?

Twisted feels to me like a grand experiment that's groping towards something that we know is there, but not quite catching it yet. I guess I/O monads feel like slightly further along the path - but they're still not the true solution. What does your system look like?

[lvh]

Greenlets are one-shot coroutines (with no implicit scheduling). They generally work with a C extension that slices the stack.

In IO frameworks that are greenlet based, the greenlet is resumed when it has stuff waiting for it.

The obvious difference to the programmer is that a greenlet won't have yield statements in them, whereas a generator would.