Apologize, for bad mouthing nested-sys in the coroutine discussion.
(not that I like this concept).

In the ISO 94 document the concept of nest-sys is indeed needed.
It is present in the convoluted explanation of DOES>.
A more reasonable, not overly clever, implementation of the concept of
a poor man's object is META. Remember: CREATE DOES> words are a data
structure coupled with a single behaviour, a kind of object.

This is META.
\ ( xtb xtd "name" -- ) generate DEA for "name".

It is most easily explained via an example:

: CONSTANT CREATE , DOES> @ ;

META replaces CREATE and DOES> meanwhile not introducing anything
new.

The above examples becomes using META :

:NONAME , ; :NONAME @ ; META CONSTANT

The specification of META is

\ ( xtb xtd "name" -- ) generate DEA for "name".

The dictionary entry (e.g. CONSTANT) identified by "name" does
the following:

On compilation :
(Think `` 12 CONSTANT ORANGUTAN ''
It parses a name and generates a dictionary entry for it.
xtb is executed and the base address is retained.

On execution of the resulting word:
xtd is executed with on the stack the base address.

The mystification disappears. Nowhere is nested-sys in sight.

I prefer { } over :NONAME.

My favorite is

{ } { } META DATA

Hint :
: VARIABLE DATA 0 , ;

Groetjes Albert
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In article <8d760e814c0d0342eb9beaa0d271a6f1d1271e3a@i2pn2.org>,
dxf <dxforth@gmail.com> wrote:

On 14/03/2025 3:19 am, albert@spenarnc.xs4all.nl wrote:

Apologize, for bad mouthing nested-sys in the coroutine discussion.
(not that I like this concept).

In the ISO 94 document the concept of nest-sys is indeed needed.
...

Unavoidable really. Nesting aka subroutine call - the process of
calling a function and when it completes, returning to the caller -
is a basic computing concept. In forth 'nest-sys' represents the
information necessary to facilitate that return. It should not be
confused with invoking a function i.e. 'xt' EXECUTE.

I've shown that the concept of nest-sys is avoidable for a language
that has the capabilities of Forth with a slight reorganisation of
the CREATE DOES> construction.

nest-sys is a ghost. You know it must be there, but only an
implementor has to deal with it. Unless you stick to CREATE DOES>,
you call this unavoidable, I don't.

Groetjes Albert.
--
Temu exploits Christians: (Disclaimer, only 10 apostles)
Last Supper Acrylic Suncatcher - 15Cm Round Stained Glass- Style Wall
Art For Home, Office And Garden Decor - Perfect For Windows, Bars,
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