[Python-Dev] Re: anonymous blocks

[Phillip J. Eby]

At 04:37 AM 4/26/05 -0700, Guido van Rossum wrote:
>*Fourth*, and this is what makes Greg and me uncomfortable at the same
>time as making Phillip and other event-handling folks drool: from the
>previous three points it follows that an iterator may *intercept* any
>or all of ReturnFlow, BreakFlow and ContinueFlow, and use them to
>implement whatever cool or confusing magic they want.

Actually, this isn't my interest at all.  It's the part where you can pass 
values or exceptions *in* to a generator with *less* magic than is 
currently required.

This interest is unrelated to anonymous blocks in any case; it's about 
being able to simulate lightweight pseudo-threads ala Stackless, for use 
with Twisted.  I can do this now of course, but "yield expressions" as 
described in PEP 340 would eliminate the need for the awkward syntax and 
frame hackery I currently use.