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Reply-To: aa...@assonance.org
In-Reply-To: <A685C4C3-1120-4420-A2F9-641C4BB1D...@kotka.de>
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	 <A685C4C3-1120-4420-A2F9-641C4BB1D...@kotka.de>
Date: Thu, 13 Aug 2009 17:23:06 -0400
Message-ID: <727e50150908131423g3d394190r7e1ed11034c94...@mail.gmail.com>
Subject: Re: Request for Discussion: user created reader macros
From: Aaron Cohen <remled...@gmail.com>
To: clojure@googlegroups.com
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On Thu, Aug 13, 2009 at 5:14 PM, Meikel Brandmeyer<m...@kotka.de> wrote:
> Hi,
>
> Am 13.08.2009 um 22:30 schrieb Brian Hurt:
>
>> Now, I can certainly see a lot of potiential downsides to this.
>> =C2=A0Redefining what #{} or #() means is just the start.
>
> I think, this is the reason Rich is not very positive for that idea: beca=
use
> nobody came up with a way of defining "namespaces" for reader macros, so
> that they don't interfere with each other.
>
>> But it'd make it a lot easier to do things with DSLs.
>
> I'm happy with macros for DSLs. Actually the macros just quasiquote their
> arguments and pass them on to actual functions.
>
>> So, what are people's thoughts?
>
> I've yet to see the desire for a self-defined reader macro. But I'm no
> Common Lisper (a Schemer actually). So I'm not used to reader macros. May=
be
> I'm missing the paradise.
>
> I'm not necessarily opposed to the idea. But I wouldn't give it high
> priority either.
>
> Sincerely
> Meikel
>
>

Would it make any difference if the scope of the reader macro was
limited to the file which defines/uses it?  Any file that wanted to
use a custom reader macro would then have to add its own
(use-reader-macro ...) statements, and there'd be no possibility for
conflicts.

Something like:

(defn comment-block-begin []
     "Dispatch function for beginning of block comments")

(use-reader-macro '#| comment-block-begin)