From 4d1d43e41fafaa5beecba57686f5d5f4146746c8 Mon Sep 17 00:00:00 2001 From: Theodor Thornhill Date: Mon, 9 Jan 2023 07:52:38 +0100 Subject: [PATCH] Add named defun for transpose-sexps-default-function (bug#60654) * lisp/simple.el (transpose-sexps-default-function): Move the lambda into its own function. (transpose-sexps-function): Refer to it by name. * etc/NEWS: Mention the change. --- etc/NEWS | 4 ++++ lisp/simple.el | 64 ++++++++++++++++++++++++++------------------------ 2 files changed, 37 insertions(+), 31 deletions(-) diff --git a/etc/NEWS b/etc/NEWS index 60dab575da6..3aa8f2abb77 100644 --- a/etc/NEWS +++ b/etc/NEWS @@ -57,6 +57,10 @@ trash when deleting. Default is nil. Emacs now can set this variable to customize the behavior of the 'transpose-sexps' function. +** New function 'transpose-sexps-default-function'. +The previous implementation is moved into its own function, to be +bound by transpose-sexps-function'. + ** New function 'treesit-transpose-sexps'. treesit.el now unconditionally sets 'transpose-sexps-function' for all Tree-sitter modes. This functionality utilizes the new diff --git a/lisp/simple.el b/lisp/simple.el index 690968ca938..c8c5542caee 100644 --- a/lisp/simple.el +++ b/lisp/simple.el @@ -8436,37 +8436,39 @@ are interchanged." (interactive "*p") (transpose-subr 'forward-word arg)) -(defvar transpose-sexps-function - (lambda (arg) - ;; Here we should try to simulate the behavior of - ;; (cons (progn (forward-sexp x) (point)) - ;; (progn (forward-sexp (- x)) (point))) - ;; Except that we don't want to rely on the second forward-sexp - ;; putting us back to where we want to be, since forward-sexp-function - ;; might do funny things like infix-precedence. - (if (if (> arg 0) - (looking-at "\\sw\\|\\s_") - (and (not (bobp)) - (save-excursion - (forward-char -1) - (looking-at "\\sw\\|\\s_")))) - ;; Jumping over a symbol. We might be inside it, mind you. - (progn (funcall (if (> arg 0) - #'skip-syntax-backward #'skip-syntax-forward) - "w_") - (cons (save-excursion (forward-sexp arg) (point)) (point))) - ;; Otherwise, we're between sexps. Take a step back before jumping - ;; to make sure we'll obey the same precedence no matter which - ;; direction we're going. - (funcall (if (> arg 0) #'skip-syntax-backward #'skip-syntax-forward) - " .") - (cons (save-excursion (forward-sexp arg) (point)) - (progn (while (or (forward-comment (if (> arg 0) 1 -1)) - (not (zerop (funcall (if (> arg 0) - #'skip-syntax-forward - #'skip-syntax-backward) - "."))))) - (point))))) +(defun transpose-sexps-default-function (arg) + "Default method to locate a pair of points for transpose-sexps." + ;; Here we should try to simulate the behavior of + ;; (cons (progn (forward-sexp x) (point)) + ;; (progn (forward-sexp (- x)) (point))) + ;; Except that we don't want to rely on the second forward-sexp + ;; putting us back to where we want to be, since forward-sexp-function + ;; might do funny things like infix-precedence. + (if (if (> arg 0) + (looking-at "\\sw\\|\\s_") + (and (not (bobp)) + (save-excursion + (forward-char -1) + (looking-at "\\sw\\|\\s_")))) + ;; Jumping over a symbol. We might be inside it, mind you. + (progn (funcall (if (> arg 0) + #'skip-syntax-backward #'skip-syntax-forward) + "w_") + (cons (save-excursion (forward-sexp arg) (point)) (point))) + ;; Otherwise, we're between sexps. Take a step back before jumping + ;; to make sure we'll obey the same precedence no matter which + ;; direction we're going. + (funcall (if (> arg 0) #'skip-syntax-backward #'skip-syntax-forward) + " .") + (cons (save-excursion (forward-sexp arg) (point)) + (progn (while (or (forward-comment (if (> arg 0) 1 -1)) + (not (zerop (funcall (if (> arg 0) + #'skip-syntax-forward + #'skip-syntax-backward) + "."))))) + (point))))) + +(defvar transpose-sexps-function #'transpose-sexps-default-function "If non-nil, `transpose-sexps' delegates to this function. This function takes one argument ARG, a number. Its expected -- 2.39.2