Re: [xml-dev] If XML is too hard for a programmer, perhaps he'd b e better off as a crossing guard

[Uche Ogbuji <uche.ogbuji@fourthought.com>]

> I would add, though, that Uche's article and references describing
> generators has prompted me to by my first Python book; I tried grokking
> Stackless but gave up after the old noggin started throwing sparks like the
> Star Trek bridge deck during a Klingon battle.

Indeed, generators are perhaps the most merciful introduction to continuations 
for a programmer of procedural heritage (as mine was).  I first ran into 
continuations in all their glory in Scheme, and I think the two months of my 
adult life about which I can remember no details must be from the period where 
my brain was recovering from the resultant explosion.

I never *really* grokked continuations until I played with Stackless Python, 
and boy did I regret missing them for so many years.  Then Python decided to 
take up just the generator speciaization of continuations, and I was 
disapointed until I learned two things:

1) Generators offer an almost guaranteed "lightbulb" moment for a decently 
trained programmer (I would measure that for this discussion as one who has 
ever had to code a variety of tree-traversal routines)

2) Once you start to really feel the generator zen, you find that you can do 
most of the cool things that continuations offer using generators along.  
David Mertz has some nice articles on IBM dW about simulating microthreads and 
coroutines using generators.


-- 
Uche Ogbuji                                    Fourthought, Inc.
http://uche.ogbuji.net    http://4Suite.org    http://fourthought.com
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