Re: [boost] De Bruijn Bind (alternate bind syntax) Interest?

Subject: Re: [boost] De Bruijn Bind (alternate bind syntax) Interest?
From: Manjunath Kudlur (keveman_at_[hidden])
Date: 2010-09-04 14:53:30

> //llam → lazy lambda is only evaluated when needed
> //_a_b → the b argument of the a nested lambda
> //_a → the a nested lambda
>
> auto fact = iff( _1_1 == 1
> Â  Â  Â  Â  Â  Â  Â  , 1
> Â  Â  Â  Â  Â  Â  Â  , llam( _2_1 * _2( _2_1 - 1 ) )
> Â  Â  Â  Â  Â  Â  Â  )
>
> ⇒ syntax sugar traslated to fix
>
> fix( lam( lam( iff( _1_1 == 1
> Â  Â  Â  Â  Â  Â  Â  Â  Â , 1
> Â  Â  Â  Â  Â  Â  Â  Â  Â , llam( _2_1 * _3_1( _2_1 - 1 ) )
> Â  Â  Â  Â  Â  Â  Â  Â  Â )
> Â  Â  Â  Â  Â  Â  )
> Â  Â  Â  Â )
> Â  );
>

I am not sure if this is entirely relevant, but there was a discussion
on boost::proto list about defining mutually recursive lambdas :
http://www.mail-archive.com/[e-mail]/msg00074.html
I haven't gone through all the discussion on this thread, but the
recursive definition of "fact" caught my eye. Can this be used for
mutually recursive functions as well?

Manjunath

> I'm also pretty confidant I can make the evaluator do tail call optimization
>
> [1] http://en.wikipedia.org/wiki/Fixed_point_combinator
> [2] http://en.wikipedia.org/wiki/Tail_call#Tail_call_optimization
>
>
> --
> David Sankel
> Sankel Software
> www.sankelsoftware.com
> 585 617 4748 (Office)
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