From df0f32f04850e7ed106a225addfa82f1b5b91f45 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Mattias=20Engdeg=C3=A5rd?= Date: Fri, 18 Sep 2020 12:49:33 +0200 Subject: [PATCH] Don't signal scan-error when moving by sexp interactively * lisp/emacs-lisp/lisp.el (forward-sexp, backward-sexp, forward-list) (backward-list, down-list, up-list, mark-sexp, kill-sexp) (backward-kill-sexp): Remove unsightly scan-error when running interactively and no further movement by sexp can be made (bug#43489). --- lisp/emacs-lisp/lisp.el | 140 +++++++++++++++++++++++++++------------- 1 file changed, 95 insertions(+), 45 deletions(-) diff --git a/lisp/emacs-lisp/lisp.el b/lisp/emacs-lisp/lisp.el index ac4ba788972..ba78d7f9b39 100644 --- a/lisp/emacs-lisp/lisp.el +++ b/lisp/emacs-lisp/lisp.el @@ -55,7 +55,7 @@ This affects `insert-parentheses' and `insert-pair'." "If non-nil, `forward-sexp' delegates to this function. Should take the same arguments and behave similarly to `forward-sexp'.") -(defun forward-sexp (&optional arg) +(defun forward-sexp (&optional arg user-error) "Move forward across one balanced expression (sexp). With ARG, do it that many times. Negative arg -N means move backward across N balanced expressions. This command assumes @@ -64,23 +64,32 @@ point is not in a string or comment. Calls If unable to move over a sexp, signal `scan-error' with three arguments: a message, the start of the obstacle (usually a parenthesis or list marker of some kind), and end of the -obstacle." - (interactive "^p") - (or arg (setq arg 1)) - (if forward-sexp-function - (funcall forward-sexp-function arg) - (goto-char (or (scan-sexps (point) arg) (buffer-end arg))) - (if (< arg 0) (backward-prefix-chars)))) - -(defun backward-sexp (&optional arg) +obstacle. If USER-ERROR is non-nil, as it is interactively, +report errors as appropriate for an interactive command." + (interactive "^p\nd") + (if user-error + (condition-case _ + (forward-sexp arg nil) + (scan-error (user-error (if (> arg 0) + "No next sexp" + "No previous sexp")))) + (or arg (setq arg 1)) + (if forward-sexp-function + (funcall forward-sexp-function arg) + (goto-char (or (scan-sexps (point) arg) (buffer-end arg))) + (if (< arg 0) (backward-prefix-chars))))) + +(defun backward-sexp (&optional arg user-error) "Move backward across one balanced expression (sexp). With ARG, do it that many times. Negative arg -N means move forward across N balanced expressions. This command assumes point is not in a string or comment. -Uses `forward-sexp' to do the work." - (interactive "^p") +Uses `forward-sexp' to do the work. +If USER-ERROR is non-nil, as it is interactively, +report errors as appropriate for an interactive command." + (interactive "^p\nd") (or arg (setq arg 1)) - (forward-sexp (- arg))) + (forward-sexp (- arg) user-error)) (defun mark-sexp (&optional arg allow-extend) "Set mark ARG sexps from point. @@ -99,50 +108,78 @@ This command assumes point is not in a string or comment." (set-mark (save-excursion (goto-char (mark)) - (forward-sexp arg) + (condition-case error + (forward-sexp arg) + (scan-error + (user-error (if (equal (cadr error) + "Containing expression ends prematurely") + "No more sexp to select" + (cadr error))))) (point)))) (t (push-mark (save-excursion - (forward-sexp (prefix-numeric-value arg)) + (condition-case error + (forward-sexp (prefix-numeric-value arg)) + (scan-error + (user-error (if (equal (cadr error) + "Containing expression ends prematurely") + "No sexp to select" + (cadr error))))) (point)) nil t)))) -(defun forward-list (&optional arg) +(defun forward-list (&optional arg user-error) "Move forward across one balanced group of parentheses. This command will also work on other parentheses-like expressions defined by the current language mode. With ARG, do it that many times. Negative arg -N means move backward across N groups of parentheses. -This command assumes point is not in a string or comment." - (interactive "^p") - (or arg (setq arg 1)) - (goto-char (or (scan-lists (point) arg 0) (buffer-end arg)))) - -(defun backward-list (&optional arg) +This command assumes point is not in a string or comment. +If USER-ERROR is non-nil, as it is interactively, +report errors as appropriate for an interactive command." + (interactive "^p\nd") + (if user-error + (condition-case _ + (forward-list arg nil) + (scan-error (user-error (if (> arg 0) + "No next group" + "No previous group")))) + (or arg (setq arg 1)) + (goto-char (or (scan-lists (point) arg 0) (buffer-end arg))))) + +(defun backward-list (&optional arg user-error) "Move backward across one balanced group of parentheses. This command will also work on other parentheses-like expressions defined by the current language mode. With ARG, do it that many times. Negative arg -N means move forward across N groups of parentheses. -This command assumes point is not in a string or comment." - (interactive "^p") +This command assumes point is not in a string or comment. +If USER-ERROR is non-nil, as it is interactively, +report errors as appropriate for an interactive command." + (interactive "^p\nd") (or arg (setq arg 1)) - (forward-list (- arg))) + (forward-list (- arg) user-error)) -(defun down-list (&optional arg) +(defun down-list (&optional arg user-error) "Move forward down one level of parentheses. This command will also work on other parentheses-like expressions defined by the current language mode. With ARG, do this that many times. A negative argument means move backward but still go down a level. -This command assumes point is not in a string or comment." - (interactive "^p") - (or arg (setq arg 1)) - (let ((inc (if (> arg 0) 1 -1))) - (while (/= arg 0) - (goto-char (or (scan-lists (point) inc -1) (buffer-end arg))) - (setq arg (- arg inc))))) +This command assumes point is not in a string or comment. +If USER-ERROR is non-nil, as it is interactively, +report errors as appropriate for an interactive command." + (interactive "^p\nd") + (if user-error + (condition-case _ + (down-list arg nil) + (scan-error (user-error "At bottom level"))) + (or arg (setq arg 1)) + (let ((inc (if (> arg 0) 1 -1))) + (while (/= arg 0) + (goto-char (or (scan-lists (point) inc -1) (buffer-end arg))) + (setq arg (- arg inc)))))) (defun backward-up-list (&optional arg escape-strings no-syntax-crossing) "Move backward out of one level of parentheses. @@ -229,26 +266,39 @@ point is unspecified." (or (< inc 0) (forward-comment 1)) (setf arg (+ arg inc))) - (signal (car err) (cdr err)))))) + (if no-syntax-crossing + ;; Assume called interactively; don't signal an error. + (user-error "At top level") + (signal (car err) (cdr err))))))) (setq arg (- arg inc))))) -(defun kill-sexp (&optional arg) +(defun kill-sexp (&optional arg user-error) "Kill the sexp (balanced expression) following point. With ARG, kill that many sexps after point. Negative arg -N means kill N sexps before point. -This command assumes point is not in a string or comment." - (interactive "p") - (let ((opoint (point))) - (forward-sexp (or arg 1)) - (kill-region opoint (point)))) - -(defun backward-kill-sexp (&optional arg) +This command assumes point is not in a string or comment. +If USER-ERROR is non-nil, as it is interactively, +report errors as appropriate for an interactive command." + (interactive "p\nd") + (if user-error + (condition-case _ + (kill-sexp arg nil) + (scan-error (user-error (if (> arg 0) + "No next sexp" + "No previous sexp")))) + (let ((opoint (point))) + (forward-sexp (or arg 1)) + (kill-region opoint (point))))) + +(defun backward-kill-sexp (&optional arg user-error) "Kill the sexp (balanced expression) preceding point. With ARG, kill that many sexps before point. Negative arg -N means kill N sexps after point. -This command assumes point is not in a string or comment." - (interactive "p") - (kill-sexp (- (or arg 1)))) +This command assumes point is not in a string or comment. +If USER-ERROR is non-nil, as it is interactively, +report errors as appropriate for an interactive command." + (interactive "p\nd") + (kill-sexp (- (or arg 1)) user-error)) ;; After Zmacs: (defun kill-backward-up-list (&optional arg) -- 2.39.2