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creating generators from function

Steven Bethard steven.bethard at gmail.com
Wed Dec 8 04:47:38 EST 2004 
Simon Wittber wrote:
> I use a coroutine/generator framework for simulating concurrent processes.
> 
> To do this, I write all my functions using the general form:
> 
> while True:
>     do stuff
>     yield None
> 
> To make these generator functions compatible with a standard thread
> interface, I attempted to write a decorator which converts a standard
> function into a generator function (code attached below).
[snip]
> @generatorize
> def f():
>     while True:
>         return 1
>         
> def g():
>     while True:
>         yield 1
> 
> print g()
> print f()

I'm a little confused as to what you're trying to do here.  The f() 
function, in particular, doesn't make much sense -- the 'while True' 
doesn't do anything since the 'return 1' is executed on the first time 
through the loop.  If you really do want to turn your functions into 
generators of the form:

while True:
     do stuff
     yield None

why can't you just do:

 >>> def generatorize(f):
...     def new_f(*args, **kwds):
...         while True:
...             f(*args, **kwds)
...             yield None
...     return new_f
...
 >>> @generatorize
... def f():
... 	return 1
...
 >>> i = f()
 >>> print i.next()
None
 >>> print i.next()
None

Basically, I've assumed that 'do stuff' is the function that's being 
wrapped.

Steve
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