Re: [stack] disallowing recursive definitions

Manfred Von Thun <[email protected]> wrote:
> > > wrote:
>  >> >  The upshot: have we in the concatenative world missed out
>  >> >  on something useful by not allowing parts to the smallest
>  >> >  programs. There is a lot one could and should discuss here,
>  >> >  but not me, not tonight.

>  > We do already do that. All concatenative languages (except 01 :-)
>  > support numbers, which are molecules by your definition. Most support
>  > strings. Joy quotations are molecules whose component parts happen to
>  > be a proper subset of Joy itself.

>  No, I mean something quite different. I did not mean that a molecule
>  consists
>  of consecutive digits (as do numerals) or of other printing characters
>  (as do most symbols). Nor do I mean strings or quotations (including lists).
>  Using the terminology of the grammar of Joy, all of the above are factors,
>  resulting in a single operation being performed on the stack. My analogy
>  was with Unix pipes. Here each command (a molecule in my meaning)
>  might consist of a primary command (an atom in my meaning)) together with
>  any (often optional) additional atoms. Some of these are additional
>  parameters,
>  some of these are command modifiers. None of these is a command
>  by itself. The Unix pipe is a concatenation of such molecules.

I see. You want not an ability to define ANY type of syntax (which is
what I described), but rather a small, standard syntax suited to
common problems.

That's an interesting problem. The syntax you propose reminds me of
strongForth's inline type specifiers: because Forth's "EXECUTE" (a
rough equivalent to Joy's "i") could have any stack effect and
StrongForth has no type inference, Becher did not define "EXECUTE",
and instead defined "EXECUTE(", a word which parsed for a close-paren
and interpreted the contents as a type signature.

I also note that Joy currently has words which would benefit from
this; for example, all the words that have a number as part of their
name could be replaced by the single word without the number, but
taking an optional argument.

REBOL does this kind of thing with the "/" (refinement) construct.

>   - Manfred

-Wm