Nimrod programming language

[kay at fiber-space.de]

On 12 Mai, 02:10, Tomasz Rola <rto... at ceti.com.pl> wrote:
> On Mon, 11 May 2009, rump... at web.de wrote:
> > > One question I ask myself upon seeing a new language is if it is possible
> > > to program amb (amb=ambiguous) operator in it. This page gives a very
> > > nice, "code first" explanation of amb and how it is supposed to work:
>
> > >http://www.randomhacks.net/articles/2005/10/11/amb-operator
>
> > Hm. I am not sure either. To me, it looks like a constraint solver by
> > using brute force.
>
> Yes, kind of. From what I understand [1], it's goal is to simulate
> nondeterministic "get right answer in one try", only this "one try"
> requires browsing the solution space (because we have only "classic"
> hardware). It is easy to use amb in wrong way, but I can see some cases
> when I would like it.

In Python you can use a generator expression. Dan Piponis example can
be stated as

g = ((i,j) for i in range(2,100) for j in range(2,i) if i*j == 481)

which doesn't require any call/cc hacks but is a deterministic "get
right in one try". Once Nimrod has coroutines it's just a matter of
sugaring them into comprehensions.

>
> [1] John McCarthy's paper still waits to be read by me, so... Ok, I have
> just had a look at it and it seems that Ruby implementation is a bit
> primitive compared to original concept. But still, this is what would be
> needed in most real life cases, I suppose.
>
> I think ability to define amb would allow me to write more concise code.
> As far as I can tell, this kind of stuff plays more and more important
> role in my programing.
>
> > It seems to require continuations. AFAIK
> > continuations are extremely hard to implement efficiently, so probably
> > it won't be done in Nimrod.
>
> Pity, a little. But not really big problem for me. Nimrod may be
> interesting anyway, time will tell :-).
>
> Regards,
> Tomasz Rola
>
> --
> ** A C programmer asked whether computer had Buddha's nature.      **
> ** As the answer, master did "rm -rif" on the programmer's home    **
> ** directory. And then the C programmer became enlightened...      **
> **                                                                 **
> ** Tomasz Rola          mailto:tomasz_r... at bigfoot.com             **