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From: Lars Brinkhoff <lars.spam@nocrew.org>
Newsgroups: comp.lang.forth
Subject: Re: Would ?EXIT work in all ANS-Forth systems?
Organization: nocrew
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Date: Mon, 15 May 2017 07:11:19 +0200
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Andrew Haley wrote:
>>>> : ?# ( ud -- ud )  #  2dup d0= if  r> drop  then ;
>>>> : #,S ( ud -- 0 0 )  begin ?#  ?#  ?#  [char] , hold  again ;
>>> 
>>> I hope that wouldn't pass review.
>
>> What matter is idea behind code. User will modify '?#' definition
>> accordingly with used Forth implementation, if necessary, or choose
>> another Forth implementation.
>
> : ?# ( ud -- ud' t )  #  2dup or ;
> : #,S ( ud -- 0 0 )
>    begin
>       ?# while  ?# while  ?# while
>       [char] , hold
>    repeat  then then ;
>
> So, not quite as cute, but it does the job.  And the reader can see
> where the exits are.  What advantage did the return stack, er,
> technique :-) bring you?

I'm reminded of Sam Falvo's 2010 article "The Declarative, Imperative,
then Inquisitive Pattern"

https://sam-falvo.github.io/2010/02/27/declarative-imperative-then-inquisitive

It does use return stack tricks quite heavily.