Subject: bug#37542: 26.1; Interactive elisp reader problems with character literals

From: Lars Ingebrigtsen <[email-masked]>
Date: Sat, 28 Sep 2019 19:21:00 +0200

Axel Svensson <[email-masked]> writes:

> To reproduce:
> 1) Start emacs with the `-Q` option.
> 2) Notice that the active buffer is *scratch* in Lisp Interaction mode.
> 3) Paste the following text into the buffer:

[...]

> '(?c ?〈)
> '(?d ?〉)

[...]

> The expected behavior in each of steps 4 and 6 is to produce these
> messages:

[...]

> (99 9001)
> (100 9002)

[...]

> Additionally, in fundamental mode, the behavior differs from the
> expected as follows:
> - Executing the second line produces a lisp error.
> - Executing the *third* line produces (99 9001).

〈 and 〉 have parenthesis syntax, so commands like backward-sexp on
〈) will stop after reaching the opening parenthesis in non-Lisp
buffers.  I think that kinda makes sense?

In Lisp buffers it doesn't do that because it requires that the opening
and closing parentheses are part of the same pair, I think?

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no