Unyeilding a permutation generator

[Jorgen Grahn]

On 3 Nov 2008 22:13:42 GMT, Marc 'BlackJack' Rintsch <bj_666 at gmx.net> wrote:
> On Mon, 03 Nov 2008 21:09:58 +0000, Jorgen Grahn wrote:
>
>> Why multi-threading?  I see no concurrency in the original algorithm.
>> There is, in my mind, nothing concurrent about 'yield'.
>
> No "real" concurrency but a generator can be seen as independent thread 
> of code where the generator code is allowed to run when `next()` is 
> called and stops itself when it ``yield``\s an object.  Sort of 
> cooperative multitasking.

Sort of ... I find it more useful to see it as an object, or something
with a state.  And I think it's a bad idea to rewrite an algorithm
using threads in order to simulate generators.

> The name "yield" is often used in concurrent 
> code like Java's or Io's `yield()` methods.

That's a completely unrelated yield, isn't it?

Meanings (1) and (3) respectively in http://en.wiktionary.org/wiki/yield:
- To give way; to allow another to pass first.
- To produce as return, as from an investment.

/Jorgen

-- 
  // Jorgen Grahn <grahn@        Ph'nglui mglw'nafh Cthulhu
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