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From: Paul Rubin <no.email@nospam.invalid>
Newsgroups: comp.lang.forth
Subject: Re: dynamic scoping in Forth in one line of code
Date: Fri, 28 Aug 2026 18:12:48 -0700
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Kragen Javier Sitaker <kragen@canonical.org> writes:
> A couple of years ago, I noticed that it’s possible to implement
> Lisp-style dynamic scoping in standard Forth in one line of code:
>
>     : (let!) dup @ over swap 2r> rot >r rot >r >r >r ! ; : let! (let!) 2r> ! ;

You need to still restore the old value when the function exits by
exception or THROW.  So you have to use something like CATCH.