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From: "B. Pym" <Nobody447095@here-nor-there.org>
Newsgroups: comp.lang.lisp,comp.lang.scheme
Subject: Re: What's the error in this macro?
Date: Sat, 21 Sep 2024 13:29:23 -0000 (UTC)
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KK wrote:

> > (defmacro sum (expression index initial condition)
> > ;; Sum $expression$ for $index$ = $initial$ and successive integers,
> > ;; as long as $condition$ holds.
> >   (let ((temp (gensym)))
> >     `(do ((,temp 0 (+ ,temp ,expression))
> >           (,index ,initial (1+ ,index)))
> >          ((not ,condition) ,temp))))
> 
> The main error with this macro is that it does something you could do
> with the standard LOOP. I.e. instead of debugging this macro, you could
> be working on the program where this macro is intended to be used:
> 

>  (loop for x from 1 while (< x 6) summing x)
>  -> 15

Gauche Scheme

(use srfi-42) ;; sum-ec

(sum-ec (:range x 1 6) x)
  ===>
15