[Edu-sig] Simple example involving threads and infinite loops.

[Andre Roberge]

Following some bug hunting, I have written an update on the blog post
mentioned in my previous message.  I think it shows very clearly how
the borg interpreters do indeed share a common state - and how
unexpected result can happen when working with communicating threads
(even those that were supposed to properly use lock and release...).

I'd be interested in getting comments from those that try it out.

André

On 7/17/07, Andre Roberge <andre.roberge at gmail.com> wrote:
> For those that happen to have downloaded Crunchy (version 0.9x), I
> have posted a very simple example[1] that illustrate some properties
> of threads, and possible interactions between them.
>
> http://crunchypython.blogspot.com/2007/07/unending-loops-and-magic-of-threads.html
>
> The idea of threads is something that should be accessible to anyone
> familiar with using a computer.  However, I can not think of a simpler
> example in any Python environment to demonstrate
> 1. How threads can allow different parts of a program to work
> independently - in this case, two different Python interpreters.
> 2. How interactions between threads make certain things (like breaking
> of an infinite loop) possible which would not be using a single
> thread.
>
> Of course, the user has to take the teacher's word (or mine) for it
> when it is stated that the two Python interpreters are running in
> separate threads.
>
> André
>
> [1]... and, as is often the case, this example has uncovered a "small"
> bug with Crunchy which you might get to see...
>