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From: anton@mips.complang.tuwien.ac.at (Anton Ertl)
Newsgroups: comp.lang.forth
Subject: Re: Nested definitions
Date: Thu, 03 Jul 2025 08:34:26 GMT
Organization: Institut fuer Computersprachen, Technische Universitaet Wien
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Ruvim <ruvim.pinka@gmail.com> writes:
>On 2025-07-02 19:12, Anton Ertl wrote:
>> The benefit of defining a normal colon definition inside another colon
>> definition eludes me, however.  Maybe mutual recursion, but the need
>> is rare and deferred words handle that well.
>
>As I can see, the idea is that the name of a nested definition has the 
>limited scope — the same as a local variable, and it is not visible 
>outside of the containing definition.

I have found the limited scope to be a hindrance, not a help: When I
want to debug, I want to call the word, but if it is not visible,
that's hard.  There is a compromise: The scope recognizer allows to
invoke a word X in a vocabulary V with the syntax V:X:

vocabulary foo  ok
also foo definitions  ok
create foo1  ok
previous definitions  ok
foo1 
*the terminal*:9:1: error: Undefined word
>>>foo1<<<
Backtrace:
kernel/recognizer.fs:89:21:              0 $7FCA47A12FF8 throw 
foo:foo1 hex. \ output: $7FCA47AA0DE8  ok

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