GNU bug report logs - #11782
24.1; closure is not self-quoting

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Message #20 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Christopher Schmidt <christopher <at> ch.ristopher.com>
To: bug-gnu-emacs <at> gnu.org
Subject: Re: bug#11782: 24.1; closure is not self-quoting
Date: Tue, 28 May 2013 23:35:08 +0100 (BST)

Stefan Monnier <monnier <at> IRO.UMontreal.CA> writes:

Hi Stefan,

> Could you expand on why you think it's severe?

I think this issue is severe because the behaviour is odd and follows
neither other mature Lispy languages nor the reference manual.

    (info "(elisp)Lambda Expressions")

    In Emacs Lisp, such a list is valid as an expression--it evaluates
    to itself.

As I said 11 month ago, I hit on this issue a few times already.  So did
others.  In most cases I had a lambda form that was eval'ed twice due to
macro expansion.

    ;; -*- lexical-binding: t -*-

    (defmacro a ()
      (let ((l (lambda () )))
        `(funcall ,l)))

    (a)

I realise there is a technical need for lambda's to evaluate to closures
in a lexical environment.  Are there any technical reasons for lexical
closures to not self-quote?

BTW I am perfectly fine with just fixing the docs.

        Christopher

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