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Re: Y combinator

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Lars Brinkhoff <lars.spam@nocrew.org> writes:
[Anton Ertl in 2002:-)]
>> Defining Y in ANS Forth (no RECURSIVE) is left as an exercise to the
>> reader:-)
>
>I read, I exercised, I posted.
>
>: y ( xt1 -- xt2 )   here tuck 2>r  1 cells allot
>   :noname r> postpone literal postpone @ r> compile, postpone ;
>   dup rot ! ;

Nice.

Now Curry's definition of Y is

Y = lambda f.(lambda x.f (x x))(lambda x.f (x x))

I am wondering what capabilities of Forth we have to remove until we
have to go to these lengths.

- anton
-- 
M. Anton Ertl  http://www.complang.tuwien.ac.at/anton/home.html
comp.lang.forth FAQs: http://www.complang.tuwien.ac.at/forth/faq/toc.html
     New standard: http://www.forth200x.org/forth200x.html
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Y combinator Lars Brinkhoff <lars.spam@nocrew.org> - 2013-10-03 09:57 +0200
  Re: Y combinator anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-10-03 13:09 +0000
    Re: Y combinator Lars Brinkhoff <lars.spam@nocrew.org> - 2013-10-07 15:06 +0200

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