From: gabriele renzi <rff_rff@...>
Date: 2005-02-15T10:12:07+09:00
Subject: Re: Printing why's (poignant) guide to ruby

Florian Gross ha scritto:


> On another note it might be interesting to have a look at concatenative 
> languages like Joy. These have something very similar to blocks as well:
> 
> [1 2 3] [2 *] map
> 
> What does that code to?
> 
> C:\dev.svn\ruby>irb -r joy
> irb(main):001:0> joy = Joy.new
> =>  #<Joy:0x2b90d00 ...>
> irb(main):002:0> joy.execute "[1 2 3] [2 *] map"; joy.stack
> => [[2, 4, 6]]

wait: you wrote a joy interpreter? that's cool :)

> It takes a list and applies the [2 *] predicate to it yielding a new 
> list. Note that Joy is stack based and utilizes reverse polish notation 
> so 2 * pushes a 2 to the stack and multiplies the item that was on top 
> before with it.

I think even more mind boggling things relate to every function being 
unary and to the implicit recursive operators :D