Re: [stack] Joy's relationship to FP + a Joy variant with combining forms

John Nowak <[email protected]> wrote:
> In short, Joy is higher order and based on composition, and FP is
> first order and based on application. What I'm wondering is what a
> first order language based on composition would look like.

> One thing to note is that a combining form for quotation is no longer
> needed since it is impossible to create objects that represent
> functions.

Hmm. So is Forth a first-order language based on composition? Seems
that way. Mind you, Forth wasn't designed with that in mind, so its
syntax is a hodge-podge, but it does seem like its semantics are
comparable.

I'm tempted to muck about with defining a suite of words in Forth that
would give it the syntax you describe. Maybe after I get my current
project into releasable form.

> While FP does not allow the definition of new combining forms, such a
> facility is undoubtedly necessary for real programming. The syntax for
> this mimics use. Note that all variables are in uppercase so as to not
> clash with function names. Here is an example of how we can define a
> 'reverse-map' combining form in terms of the 'fold' combining form:

>     Combining form version:
>     reverse-map(F) = null fold(F cons)

I'm thinking that this works using pure textual replacement. Is this
right? If so, this is a perfect match for Forth (and more regular than
the current Forth conventions).

In short, I this looks like a nice model to give a concatenative stack
language disciplined access to its own source code.

> - John

-Wm