How to let a loop run for a while before checking for break condition?

[Fredrik Lundh]

Sorin Schwimmer wrote:

> I am thinking on something in the following form:
> 
> <code>
> import time
> import thread
> 
> delay=True
> 
> def fn()
>   global delay
>   time.sleep(<your_amount_of_time_in_seconds>)
>   delay=False
> 
> thread.start_new_thread(fn,())
> 
> while delay:
>  <statement 1>
>  <statement 2>
>  ...

if the loop calls out to python functions at least occasionally, you can 
eliminate the flag by abusing the interpreter's stack check mechanism:

import time, thread, sys

def alarm():
     time.sleep(1.234)
     sys.setrecursionlimit(1)

thread.start_new_thread(alarm, ())

def do_some_work():
     pass

t0 = time.time()
try:
     while 1:
	do_some_work()
except RuntimeError:
     pass
print time.time() - t0

</F>