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why 'lambda' and 'reduce'?

Irmen de Jong irmen at -NOSPAM-REMOVETHIS-xs4all.nl
Thu Jun 12 16:36:52 EDT 2003 
John Roth wrote:
> "Manuel Garcia" <news at manuelmgarcia.com> wrote in message
> news:arnfevstdtqohla2l39717ch56saip8qce at 4ax.com...
> 
>>If anyone ever asks for what good are 'lambda' and 'reduce', show them
>>this...
>>
>>print (lambda p:p[0]+'.'+p[1:])(
>>    str((lambda(x,y,t,a):2L*x*x//a)(
>>        (lambda F:(lambda S:reduce(
>>            lambda(x,y,t,a),_:((x+y)//2L,
>>                S((x*y)//F),2L*t,
>>                (a-(t*(((x+y)//2L)**2-
>>                       (S((x*y)//F))**2))//F)),
>>            [0]*13,(F,(F*F)//S(2L*F),2L,F//2L)))(
>>                lambda n:reduce(lambda x,_:(
>>                    x-x//2L+(n*F)//(2L*x)),
>>                [0]*15,
>>                n//2L)))(10L**(5010))))[:5000])
>>
>>You have to be a bit patient with this one...
> 
> 
> One thing is perfectly clear. Unless someone paid
> me to do it, I wouldn't look at it. And part of
> the agreement would be to refactor it into something
> at least marginally readable.

A million times zero readability is still zero readability ;-)

Anyway it ran quite fast indeed... somehow I don't expect
this kind of unreadable and horribly nested code to run
fast too. Never mind. :-)

--Irmen
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