Stackless & String-processing

[Christian Tismer]

Greg Ewing wrote:
> 
> Neel Krishnaswami wrote:
> >
> > What's the difference, exactly? AFAICT you need to save the execution
> > state when suspending both coroutines and generators, but I might be
> > missing something obvious....
> 
> The crucial difference is that a generator is never resumed
> after its caller has returned. This means that the generator's
> state can be pushed onto the same stack as the caller's.

Fine.

> A coroutine, on the other hand, can outlive the context in
> which it was created, and therefore needs a stack all of
> its own.

Smell of danger...

> Another way to think about it is that a generator call is
> equivalent to an ordinary call where one of the parameters
> is a procedure. For example, where in "generator python"
> you might write

...

> If Python had something akin to Smalltalk code blocks,
> generators wouldn't be needed. It would be nifty to
> be able to write something like
> 
>   for_each_even_number_up_to(42) -> (e):
>     print e, "is an even number!"

Traceback (innermost last):
  File "<inbox:Re: Stackless & String-processing>", line 22, in claim
SemanticMisconceptionError: 
     things should be made as simple as possible, but not any simpler
>>> #:-)

>>> # sorry did you really mean that? 
>>> # Where is your generator's state?
>>> # how would you do backtracking?

hoping-that-I'm-misconcepted-and-not-you-ly y'rs - chris

-- 
Christian Tismer             :^)   <mailto:tismer at appliedbiometrics.com>
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