Joy, Lambdas, Combinators, Procedures

btanksley@hifn.com btanksley@hifn.com
Thu, 27 Jan 2000 20:23:20 -0800


> From: iepos@tunes.org [mailto:iepos@tunes.org]

> > I *think* I do, but what I know about the number three 
> > would indicate that
> > Joy supports it fully.  I'm trying to figure out why you 
> > say it doesn't.

> Well.. The meaning Joy associates with "3" is slightly different
> from the ordinary English meaning of "three".

I think what you're trying to say is that Joy implicitly *does* something
with the 3, instead of simply letting it exist in nothingness until some
command is applied to it.  Specifically, Joy 'pushes' the 3 on the stack.

But this is really no different from any other language -- if you can _use_
the three, you have to put it somewhere, and that means that something else
has to be overwritten or pushed aside.

> Anyway, I was
> probably being a bit silly in suggesting that this is a serious
> problem with Joy.

Grin.

> That the meaning differs may make it a 
> little harder 
> to read and write programs, but this is probably a matter of
> taste.

Good grief, no!  Didn't you read the manuals?  Joy has problems, but it's
_certainly_ not this one!  Programs in Joy are generally *dramatically*
easier to understand (that is, realize what proofs are implied) and even to
prove things about.

> Anyway, I find Joy to be quite an interesting system. But,
> I don't know that its approach of using composition and quotation
> is fundamentally superior to a purely applicative approach.

Read the manuals -- it's so clearly superior it's not even funny.

> I am much more familiar with applicative style,
> and will probably continue to use it in making my toy system. 

That's a good point.  Using the system you're comfortable is the right thing
to do when you're building a system.

I do hope you'll take the time to read the docs for Joy; they're amazingly
clear and fun to read.

> - "iepos" (Brent Kerby)

-Billy