Re: [Chicken-users] amb egg bug/confusion

[Jörg F . Wittenberger]

On Mar 19 2012, Matt Welland wrote:

> On Mon, Mar 19, 2012 at 5:55 AM, Alan Post 
> <address@hidden>wrote:
>
> > On Thu, Mar 15, 2012 at 01:38:19AM +0100, Thomas Chust wrote:
> > > On Wed, 2012-03-14 at 18:23 -0600, Alan Post wrote:
> > > > [...]
> > > >   (pretty-print (let ((s (amb 0 1 2))) (amb-collect s)))
> > > > [...]
> > > > produces:
> > > > [...]
> > > >   (0)
> > > > [...]
> > >
> > > Hello,
> > >
> > > to me this behaviour looks correct. amb-collect is supposed to 
> > > collect all the different values its argument can take on, but in your 
> > > example s is not an ambivalent expression -- the fact that s is bound 
> > > to a value produced by amb only makes the let expression ambivalent.
> > >
> > > To phrase it more technically: Every amb-collect creates a new 
> > > dynamic scope for backtracking. Any ambivalence introduced in that 
> > > dynamic scope will be resolved and the results will be collected but 
> > > any outer dynamic scope will not be affected.
> > >
> >
> > Thomas, John,
> >
> > Thank you both very much.  I did manage to start properly using the
> > amb egg, and completed a one-off homework assignment:
> >
> >
> >  
> >  
> > https://github.com/alanpost/permaculture-design-course/blob/master/guild/README
> >
> > amb is very neat.  I'll likely throw larger datasets and more
> > interesting constraints at it as I continue to explore this
> > problem space.
>
> Wow, another permaculturist on the chicken scheme list, what is the
> probability of that? I got my design certification just over a year ago.
> Nice work on the guild design! Do you have further plans for the code?

Wow!  I'm not a permaculturist.  I just got introduced to the site.

@Alan: nice work, really!

What kept me reading: if permacultures "ecological design system for 
sustainability in all aspects of human endeavor" where taken literally and 
"software development" where taken as one "aspect of human endeavor" then 
the whole idea of naming a compiler "chicken" should raise the probability 
of users relating to permacultural ideas far above any doubt that Felix is 
the one to be hanged for gathering this type of persons. ;-)

(Saying so, because askemos.org is nothing but the same idea:
permaculture; for the persistent data in Askemos case,
compiler in chickens case. So I might have been driven here by the same
force.)

/Jörg


> > -Alan
> > --
> > .i ma'a lo bradi cu penmi gi'e du
> >
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