bug#16201: 24.3.50; error expanding pcase with a pred clause

[Michael Heerdegen]

Hi,

sorry if this is a known issue.

In emacs -Q (current trunk), save the following snipped

--8<---------------cut here---------------start------------->8---
(require 'pcase)

(defun test-buffer-file-name ()
  (pcase buffer-file-name
    (`nil                   'not-a-file)
    ((pred file-writable-p) 'writable)
    (_                      'not-writable)))
--8<---------------cut here---------------end--------------->8---

into a file.  Then, M-: (byte-compile-file buffer-file-name).  You get
an error:

  pcase-bug.el:3:1:Error: Wrong type argument: stringp, nil

Same with C-x C-e with point after the defun.

BTW, (require 'pcase) is necessary in the recipe.  If pcase has not yet
been loaded, the error doesn't happen.  Instead you can compile or eval
the defun (once), and it works as expected!


Thanks,

Michael.




In GNU Emacs 24.3.50.1 (x86_64-unknown-linux-gnu, GTK+ Version 3.8.4)
 of 2013-12-20 on drachen
Windowing system distributor `The X.Org Foundation', version 11.0.11403000
System Description:     Debian GNU/Linux testing (jessie)

Configured using:
 `configure --prefix=/usr/local/built/'

Important settings:
  value of $LC_ALL: de_DE.utf8
  value of $LC_COLLATE: C
  value of $LC_TIME: C
  value of $LANG: de_DE.utf8
  locale-coding-system: utf-8-unix

Major mode: Emacs-Lisp