GNU bug report logs - #76132
Clojure-style auto-gensyms for macros

Previous Next

Full log

Message #14 received at 76132 <at> debbugs.gnu.org (full text, mbox):

From: Tassilo Horn <tsdh <at> gnu.org>
To: Drew Adams <drew.adams <at> oracle.com>
Cc: "76132 <at> debbugs.gnu.org" <76132 <at> debbugs.gnu.org>
Subject: Re: [External] : bug#76132: Clojure-style auto-gensyms for macros
Date: Sat, 08 Feb 2025 08:07:46 +0100

Drew Adams <drew.adams <at> oracle.com> writes:

>> (defmacro foo [x y]
>>   `(let [xv# ,x
>>          yv# ,y]
>>      (do-stuff (* xv# xv#) (* yv# yv#))))
>> 
>> where each symbol ending in # will be replaced
>> by a unique gensymed symbol (per name).
>> Would there be interest in adding something
>> like that to Elisp?
>
> So you could no longer let-bind a variable
> whose name ends in `#', to get a normal let
> binding?  (Admittedly, you need to write that
> as `\#' in the source code.)

No, have you looked at the file I attached?  You will see the feature is
implemented by a macro itself, so if you don't like it, don't use it.

> Doesn't sound like an improvement, to me.
> A priori, I'm not in favor of limiting the
> names you can use for variables.
>
> That would be especially pernicious with let
> bindings of dynamic ("special") variables.

How many special variables are there ending in # (or actually $ which I
use in my example)?

Bye,
Tassilo

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.