Re: [stack] disallowing recursive definitions

Christopher Diggins <[email protected]> wrote:
> Stevan Apter <[email protected]> wrote:
>  > i'm still puzzled why authors of concatenative languages like cat and factor
>  > have resisted the incorporation of array primitives into their languages.

It shouldn't be a puzzle... They don't understand. It's hard to get
started learning about it.

The existing array languages are, with only two exceptions, closed
source. (The early J interpreter was available, although I don't know
how to get it now, and I couldn't ever figure out how to read it.) A+
is unreservedly open source, of course, as is QNIAL. I found A+ to be
very hard to figure out, QNIAL fairly easy.

>  Map, filter, fold, etc. are all part of the core Cat language. I
>  consider all of these array primitives.

I suppose they technically are. They're just a beginning, though.

> The Cat concept of list is
>  more or less analgous to an array, but is agnostic about
>  implementation details. An implementation is left to its own devices
>  as to what the performance characteristics of lists are. Sorry its not
>  more clear in the current documentation.

That's a pretty important point, really. It makes the difference
between an O(n) implementation and an O(n^2) one. I'd really rather it
be specified.

>  > my sense is that programmers (and language designers) *still* do not
>  > appreciate the power of array programming.

We don't. I don't. I wish I did, but it's a steep hill to climb.

>  Nonetheless, your original point is still valid that some more array
>  processing primitives would be valuable in Cat. I'll add some to the
>  specification.

I like the implicit iteration.

>  - Christopher

-Wm