>From 3dc513bc01decf9774f9ce5974abca30cbd71805 Mon Sep 17 00:00:00 2001 From: Arnold Noronha Date: Sat, 2 May 2020 11:24:22 -0700 Subject: [PATCH] Use a temporary-buffer before calling ido-ignore-item-p multiple times And locally set CASE-FOLD-SEARCH. Setting CASE-FOLD-SEARCH 1000s of times if CASE-FOLD-SEARCH is not locally set is super slow because it would have to update the bindings in each buffer (or, that is my understanding. See the warning at: https://www.gnu.org/software/emacs/manual/html_node/elisp/Intro-to-Buffer_002dLocal.html#Intro-to-Buffer_002dLocal) --- lisp/ido.el | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) diff --git a/lisp/ido.el b/lisp/ido.el index 81883402ad..22b3729097 100644 --- a/lisp/ido.el +++ b/lisp/ido.el @@ -3407,13 +3407,18 @@ ido-make-merged-file-list (defun ido-make-buffer-list-1 (&optional frame visible) "Return list of non-ignored buffer names." - (delq nil - (mapcar - (lambda (x) - (let ((name (buffer-name x))) - (if (not (or (ido-ignore-item-p name ido-ignore-buffers) (member name visible))) - name))) - (buffer-list frame)))) + (with-temp-buffer + ;; Each call to ido-ignore-item-p LET-binds case-fold-search. + ;; That is slow if there's no buffer-local binding available, + ;; roughly O(number of buffers). This hack avoids it. + (setq-local case-fold-search nil) + (delq nil + (mapcar + (lambda (x) + (let ((name (buffer-name x))) + (if (not (or (ido-ignore-item-p name ido-ignore-buffers) (member name visible))) + name))) + (buffer-list frame))))) (defun ido-make-buffer-list (default) "Return the current list of buffers. -- 2.20.1