bug#15969: 24.3.50; erc-button fails with error

[Eric Hanchrow]

I started "erc" with M-x erc RET.  

In an erc buffer, I moved point onto a nick that appeared at the left margin.

I typed RET whois RET.

I expected to see a message like this appear in the erc buffer:

        *** fledermaus is Vivek Dasmohapatra 
(~vivek@87-127-114-209.static.enta.net)

Instead, I saw in the echo area:

         eval: Symbol's value as variable is void: nick

After some back-and-forth with fledermaus, I wound up deleting the ``-*-
lexical-binding:t -*-`` from the top of erc-button.el, recompiling and
reloading that file ... and that made it work again.  I don't understand
why.




In GNU Emacs 24.3.50.1 (i686-pc-linux-gnu)
 of 2013-08-31 on ip-10-171-85-229
System Description:     Ubuntu 12.04.3 LTS

Configured using:
 `configure --without-x'

Important settings:
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: ERC

Minor modes in effect:
  erc-list-mode: t
  erc-menu-mode: t
  erc-autojoin-mode: t
  erc-ring-mode: t
  erc-networks-mode: t
  erc-pcomplete-mode: t
  erc-track-mode: t
  erc-track-minor-mode: t
  erc-match-mode: t
  erc-button-mode: t
  erc-fill-mode: t
  erc-stamp-mode: t
  erc-netsplit-mode: t
  erc-irccontrols-mode: t
  erc-noncommands-mode: t
  erc-move-to-prompt-mode: t
  erc-readonly-mode: t
  diff-auto-refine-mode: t
  global-auto-revert-mode: t
  shell-dirtrack-mode: t
  recentf-mode: t
  ido-everywhere: t
  display-time-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t
  abbrev-mode: t

Recent input:
b s h e RET c d SPC / u s r / l o c TAB s r TAB e m 
TAB l i TAB s TAB e r c RET g i t SPC l o g SPC - - 
a l l SPC - - SPC e r c - b u TAB RET C-c C-p ESC 0 
C-l C-x b C-n RET o d d l y , SPC n o t h j i n g SPC 
s i g n i f i c a n t SPC h a s SPC b e e n SPC d o 
n e SPC t o SPC t h a t SPC f i l e SPC s i n c e SPC 
S t e f a n ' s SPC c h a n g e . SPC SPC W h y SPC 
a m SPC I SPC t h e SPC o n l y SPC o n e SPC c o m 
p l a i n i n g ? RET A p a r t C-a ( C-e SPC f r o 
m SPC m y SPC p r o p e n s i t y SPC t o SPC w h i 
n e ) RET C-x b C-n RET C-x n w C-x v l D C-x 1 n n 
º C-l n n n n n n n n n n N N p p C-n C-p C-h c C-g 
ESC < C-s - b u t t o n C-s C-s C-a n ESC 0 C-l n q 
C-c C-@ s h o SPC n u f f RET t x RET ESC x r e p o 
r t - e m TAB RET

Recent messages:
Wrote /mnt/emacs/lisp/erc/erc-button.elc
Checking /mnt/emacs/lisp/erc/... [33 times]
Done (Total of 1 file compiled, 34 skipped)
Mark saved where search started
Making completion list...
/usr/local/src/emacs/lisp/erc ~/homedir 
Finding changes in ....
C-g runs the command keyboard-quit
Mark set
Mark saved where search started

Load-path shadows:
~/.emacs.d/custom hides /usr/local/src/emacs/lisp/custom
/home/erich/.emacs.d/elpa/tabulated-list-20120406.2251/tabulated-list hides 
/usr/local/src/emacs/lisp/emacs-lisp/tabulated-list

Features:
(shadow mail-extr emacsbug message rfc822 mml mml-sec mm-decode
mm-bodies mm-encode mailabbrev gmm-utils mailheader reposition
two-column autoconf autoconf-mode xt-mouse ruler-mode fringe scroll-bar
hexl wdired arc-mode archive-mode finder magit loadhist esh-var esh-io
esh-cmd esh-opt esh-ext esh-proc esh-arg esh-groups eshell esh-module
esh-mode esh-util ediff-merg ediff-wind ediff-diff ediff-mult ediff-help
ediff-init ediff-util ediff gh-issues gh-pulls gh-repos lui-format lui
tracking tar-mode shorten autoload lisp-mnt iswitchb cmuscheme js imenu
find-dired browse-url pcmpl-gnu sort browse-kill-ring nxml-uchnm rng-xsd
xsd-regexp rng-cmpct rng-nxml rng-valid rng-loc rng-uri rng-parse
nxml-parse rng-match rng-dt rng-util rng-pttrn nxml-ns nxml-mode
nxml-outln nxml-rap nxml-util nxml-glyph nxml-enc xmltok sgml-mode
cus-edit cus-start cus-load tabify vc-annotate sql-indent sql log-edit
org-table novice cperl-mode term ehelp electric python erc-truncate
debug geiser-mode geiser-xref geiser-racket geiser-guile geiser-repl
geiser-image geiser-doc geiser-compile geiser-debug geiser-menu
geiser-company geiser-autodoc info-look geiser geiser-edit etags
geiser-completion geiser-eval geiser-connection tq geiser-syntax
geiser-log geiser-popup geiser-impl geiser-custom geiser-base scheme
ffap mule-util sh-script smie executable rect org-element org-wl org-w3m
org-vm org-rmail org-mhe org-mew org-irc org-jsinfo org-infojs org-html
org-exp ob-exp org-exp-blocks org-agenda org-info org-gnus org-docview
org-bibtex bibtex org-bbdb org ob-tangle ob-ref ob-lob ob-table
org-footnote org-src ob-comint ob-keys org-pcomplete org-list org-faces
org-entities noutline outline org-version ob-emacs-lisp ob org-compat
org-macs ob-eval org-loaddefs cal-menu calendar cal-loaddefs dired-aux
descr-text hl-line whitespace gnutls url-cache cc-langs cc-mode cc-fonts
cc-guess cc-menus cc-cmds cc-styles cc-align cc-engine cc-vars cc-defs
disp-table jka-compr apropos epa-file conf-mode iso-transl add-log
log-view pcvs-util vc vc-dispatcher edit-list erc-spelling flyspell
ispell dabbrev view misearch multi-isearch pcmpl-unix smerge-mode
network-stream erc-list erc-menu erc-join erc-ring erc-networks
erc-pcomplete erc-track erc-match erc-button erc-fill erc-stamp
erc-netsplit erc-goodies erc erc-backend erc-compat pp color help-mode
xterm woman man eldoc gist gh-gist gh-oauth gh-api logito gh-cache
pcache gh-auth gh-common gh-url url-http tls url url-proxy url-privacy
url-expand url-methods url-history mailcap url-auth mail-parse rfc2231
url-cookie url-domsuf url-gw gh-profile json timezone eieio-base
magit-cherry magit-bisect magit-key-mode epa epg epg-config diff-mode
easy-mmode git-rebase-mode thingatpt git-commit-mode magit-compat vc-git
derived autorevert filenotify paste-to-dropbox path server starttls
smtpmail sendmail rfc2047 rfc2045 ietf-drums mail-utils warnings
url-util url-parse url-vars grep compile find-func ibuf-ext ibuf-macs
ibuffer tramp-cache tramp-sh tramp tramp-compat auth-source gnus-util
mm-util mail-prsvr password-cache tramp-loaddefs trampver shell
pcomplete comint ansi-color ring format-spec advice help-fns recentf
tree-widget wid-edit ido dired-x dired edmacro kmacro regexp-opt
perl-extras cl-macs gv cl cl-loaddefs cl-lib perl-mode autoinsert
eshell-manual-autoloads gist-autoloads finder-inf gh-autoloads eieio
byte-opt bytecomp byte-compile cconv eieio-core logito-autoloads
lui-autoloads info tool-bar easymenu pcache-autoloads package time image
rx uniquify midnight time-date ediff-hook vc-hooks lisp-float-type
tabulated-list newcomment lisp-mode prog-mode register page menu-bar
rfn-eshadow timer select mouse jit-lock font-lock syntax facemenu
font-core frame cham georgian utf-8-lang misc-lang vietnamese tibetan
thai tai-viet lao korean japanese hebrew greek romanian slovak czech
european ethiopic indian cyrillic chinese case-table epa-hook
jka-cmpr-hook help simple abbrev minibuffer nadvice loaddefs button
faces cus-face macroexp files text-properties overlay sha1 md5 base64
format env code-pages mule custom widget hashtable-print-readable
backquote make-network-process dbusbind gfilenotify multi-tty emacs)