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From: anton@mips.complang.tuwien.ac.at (Anton Ertl)
Newsgroups: comp.lang.forth
Subject: Re: value-flavoured structures (was: Avoid treating the stack as an array)
Date: Thu, 03 Oct 2024 15:58:58 GMT
Organization: Institut fuer Computersprachen, Technische Universitaet Wien
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Ruvim <ruvim.pinka@gmail.com> writes:
>On 2024-09-15 20:16, Anton Ertl wrote:
>> A major merit for value-flavoured structures is that you can change
>> the field size (e.g, from 1 byte to 2 bytes or vice versa) without
>> changing all the code accessing those fields.  That's independent of
>> cell size.
>
>Yes, you can change the field size, but only as far as its value 
>occupies the same number of a stack items and the stack is the same.

Yes.  But you can switch between different sizes that all fit into a
cell, or between different memory sizes of floats without changing the
rest of the code.

>Similar for the word `to` - `to` applies to the words created with 
>`value`, `fvalue`, `2value`. But the source code around `to foo` (and 
>`foo`) depends on the kind of `foo`, so the kind of `foo` cannot be 
>changed without changing the source code around where it is used.

That's just as for reading the value-flavoured field; if a field
pushes one cell, TO to the field also consumes one cell; likewise for
float fields.

- anton
-- 
M. Anton Ertl  http://www.complang.tuwien.ac.at/anton/home.html
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