Quoting John Clark <[EMAIL PROTECTED]>:
> import sys
>
> def neverEndingStatus(currentChar_ = '|'):
> while 1:
> if currentChar_ == '|':
> currentChar_ = '\\'
> elif currentChar_ == '\\':
> currentChar_ = '-'
> elif currentChar_ == '-':
> currentChar_ = '/'
> elif currentChar_ == '/':
> currentChar_ = '|'
> yield currentChar_
>
>
> x = neverEndingStatus()
>
> def Test1():
> for w in range(1, 100):
> sys.stderr.write('\b'+x.next())
> for z in range(1, 10000):
> z = z + 1
One of the big uses for generators is in loops. eg:
>>> import time
>>> def nes():
... chars = ('|', '\\', '-', '/')
... i = 0
... while True:
... yield chars[i]
... i = (i + 1) % len(chars)
...
>>> for c in nes():
... print c,
... time.sleep(0.5)
...
| \ - / | \ - / | \ - / | \ - / | \ - / | \ ...
Of course, you'll need _some_ way of breaking out of the loop eventually (either
a 'break' statement in the for loop, or something in nes() to raise
StopIteration, which will cause the for loop to exit naturally).
--
John.
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