Re: Y combinator

Newsgroups	comp.lang.forth
Subject	Re: Y combinator
References	<a4aljf$2q2$1@news.tuwien.ac.at> <85eh82hjlr.fsf@junk.nocrew.org> <2013Oct3.150934@mips.complang.tuwien.ac.at>
From	Lars Brinkhoff <lars.spam@nocrew.org>
Organization	nocrew
Date	2013-10-07 15:06 +0200
Message-ID	<85vc19dydi.fsf@junk.nocrew.org> (permalink)

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anton@mips.complang.tuwien.ac.at (Anton Ertl) writes:
> Lars Brinkhoff <lars.spam@nocrew.org> writes:
>>: 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.

"Why" indeed.

I was tempted to submit this smaller version, but felt that the named
definition was not quite in the spirit of the original Y.

: y ( xt "name" -- )   >in @ create >in ! , ' ,  does> 2@ execute ;

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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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