Dear developers,
delete-trailing-whitespace in Emacs 26 for large files is very slow.
But in Emacs 25, it took about 0.003s.
A similar code to the following is used in delete-trailing-whitespace. And it is slow for large files.
(save-excursion
(let ((end-marker nil))
(goto-char (point-min))
(with-syntax-table (make-syntax-table (syntax-table))
(modify-syntax-entry ?\f "_")
(modify-syntax-entry ?\n "_")
(re-search-forward "\\s-+$" end-marker t))))
Best regards,
Sho Takemori
In GNU Emacs 26.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.18.9)
of 2017-03-13 built on 500-270jp
Repository revision: cf670b49a7704d63575863f832426d32bf6a8c3c
Windowing system distributor 'The X.Org Foundation', version 11.0.11804000
System Description: Ubuntu 16.04.2 LTS
Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
delete-backward-char: Text is read-only
(1.6173726940000002 0 0.0)
Quit
Configured using:
'configure --with-sound=no --with-modules'
Configured features:
XPM JPEG TIFF GIF PNG RSVG IMAGEMAGICK GPM DBUS GCONF GSETTINGS NOTIFY
ACL LIBSELINUX GNUTLS LIBXML2 FREETYPE M17N_FLT LIBOTF XFT ZLIB
TOOLKIT_SCROLL_BARS GTK3 X11 MODULES
Important settings:
value of $LC_MONETARY: ja_JP.UTF-8
value of $LC_NUMERIC: ja_JP.UTF-8
value of $LC_TIME: ja_JP.UTF-8
value of $LANG: ja_JP.UTF-8
value of $XMODIFIERS: @im=ibus
locale-coding-system: utf-8-unix
Major mode: Org
Minor modes in effect:
diff-auto-refine-mode: t
shell-dirtrack-mode: t
tooltip-mode: t
global-eldoc-mode: t
electric-indent-mode: t
mouse-wheel-mode: t
tool-bar-mode: t
menu-bar-mode: t
file-name-shadow-mode: t
global-font-lock-mode: t
font-lock-mode: t
blink-cursor-mode: t
auto-composition-mode: t
auto-encryption-mode: t
auto-compression-mode: t
line-number-mode: t
transient-mark-mode: t
Load-path shadows:
None found.
Features:
(shadow sort mail-extr emacsbug message puny rfc822 mml mml-sec epa
derived epg epg-config mm-decode mm-bodies mm-encode mail-parse rfc2231
mailabbrev gmm-utils mailheader sendmail benchmark vc-git diff-mode
org-element org-rmail org-mhe org-irc org-info org-gnus gnus-util rmail
rmail-loaddefs rfc2047 rfc2045 ietf-drums mm-util mail-prsvr mail-utils
org-docview doc-view jka-compr image-mode dired dired-loaddefs
org-bibtex bibtex org-bbdb org-w3m org org-macro org-footnote
org-pcomplete org-list org-faces org-entities noutline outline
easy-mmode org-version ob-emacs-lisp ob ob-tangle ob-ref ob-lob ob-table
ob-exp org-src ob-keys ob-comint ob-core ob-eval org-compat org-macs
org-loaddefs find-func seq cal-menu calendar cal-loaddefs tramp
tramp-compat tramp-loaddefs trampver ucs-normalize shell pcomplete
comint ansi-color ring parse-time format-spec advice auth-source cl-seq
eieio byte-opt subr-x bytecomp byte-compile cl-extra help-mode easymenu
cconv eieio-core cl-macs gv eieio-loaddefs cl-loaddefs pcase cl-lib
password-cache time-date mule-util japan-util tooltip eldoc electric
uniquify ediff-hook vc-hooks lisp-float-type mwheel term/x-win x-win
term/common-win x-dnd tool-bar dnd fontset image regexp-opt fringe
tabulated-list replace newcomment text-mode elisp-mode lisp-mode
prog-mode register page menu-bar rfn-eshadow isearch timer select
scroll-bar mouse jit-lock font-lock syntax facemenu font-core
term/tty-colors frame cl-generic cham georgian utf-8-lang misc-lang
vietnamese tibetan thai tai-viet lao korean japanese eucjp-ms cp51932
hebrew greek romanian slovak czech european ethiopic indian cyrillic
chinese composite charscript case-table epa-hook jka-cmpr-hook help
simple abbrev obarray minibuffer cl-preloaded 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 dbusbind inotify dynamic-setting system-font-setting
font-render-setting move-toolbar gtk x-toolkit x multi-tty
make-network-process emacs)
Memory information:
((conses 16 275028 6205)
(symbols 48 28629 1)
(miscs 40 79 128)
(strings 32 45484 10223)
(string-bytes 1 1457234)
(vectors 16 45224)
(vector-slots 8 888199 4865)
(floats 8 105 76)
(intervals 56 394 5)
(buffers 976 12)
(heap 1024 30354 1435))