On 13/10/2011 15:13, Stefan Behnel wrote:
Martin P. Hellwig, 13.10.2011 14:35:
I was wondering if there could be an advantage to add another control
flow
statement.
Changes at that level must be very well justified, are often rejected
for the reason of being not too complicated to write in some other form
and are close to impossible to get accepted when requiring a new keyword.
Also, the right place to discuss (and, more importantly, search for
previous) ideas about language changes is the python-ideas mailing list.
For the purpose of this writing let's say "ooo" which stands for 'out of
order'.
For example;
def do_something():
a = 4
b = 2
c = 1
ooo:
a += 1
b += 2
c += 3
print(a, b, c)
What I would expect to happen that all statements within the ooo block
may
be executed out
of order. The block itself waits till all statements are returned before
continuing.
This looks like a rather special case. What if you need more than one
statement to accomplish a single step?
Aah yes haven't thought about that, was more thinking like wrap multiple
steps in a function and put that as one line, but yeah that kind of
stuff gets very unpythonic very quickly.
What if the number of parallel
tasks is not fixed at coding time? I don't think there are many problems
that you can solve with this feature.
Also: the GIL will not allow you to take a major advantage from the
parallel execution of a set of statements, as only one of the statements
can use the interpreter at a time.
Well I was more or less thinking in the line that the interpreter when
parsing such a statement can, if there are multiple cpu's available,
fire the appropriate amount of other interpreters and do all the passing
and locking of data for you.
And, on a related note: Cython has freshly gained support for parallel
loops based on OpenMP, so you may be able to solve your problem with
Cython instead of using plain Python.
Well funny enough I don't really have a problem with it, I am a happy
consumer of multiprocessing, but I was just wondering if there would be
a way to do it simpler and more pythonic.
Stefan
Thanks for your feedback it was very enlightening although for what the
idea is concerned disappointing as it more or less makes it obvious that
such a thing is a no-go.
Cheers,
Martin
--
http://mail.python.org/mailman/listinfo/python-list
