From 3f23e559cae5ce864aef2c15e990f6beb5484eb7 Mon Sep 17 00:00:00 2001 From: Spencer Baugh Date: Sun, 9 Jul 2023 12:16:28 -0400 Subject: [PATCH] Support displaying function name in the header line In some languages, the function name as displayed in the mode-line by which-func-mode can be quite long. It's useful to be able to display it in the header-line instead. Let's support that. * lisp/progmodes/which-func.el (which-func-display) (which-func--use-header-line, which-func--use-mode-line): Add. (Bug#64533) (which-func-try-to-enable): Support which-func--use-header-line. (which-func--disable): Add, to support which-func--use-header-line. (which-func-ff-hook, which-func-update-1): Use which-func--disable. --- doc/emacs/programs.texi | 10 +++++++-- etc/NEWS | 9 ++++++++ lisp/progmodes/which-func.el | 42 ++++++++++++++++++++++++++++++------ 3 files changed, 53 insertions(+), 8 deletions(-) diff --git a/doc/emacs/programs.texi b/doc/emacs/programs.texi index a0e0fc06385..41780a95489 100644 --- a/doc/emacs/programs.texi +++ b/doc/emacs/programs.texi @@ -335,8 +335,8 @@ Which Function @cindex current function name in mode line Which Function mode is a global minor mode (@pxref{Minor Modes}) -which displays the current function name in the mode line, updating it -as you move around in a buffer. +which displays the current function name in the mode line or header +line, updating it as you move around in a buffer. @findex which-function-mode @vindex which-func-modes @@ -349,6 +349,12 @@ Which Function @code{t} (which means to support all available major modes) to a list of major mode names. +@vindex which-func-display + By default, Which Function mode displays the current function name +using the mode line. Customize @code{which-func-display} to +@code{header}, @code{mode}, or @code{mode-and-header} to use the +header line, mode line, or both, respectively. + @node Program Indent @section Indentation for Programs @cindex indentation for programs diff --git a/etc/NEWS b/etc/NEWS index 9c99cf6c725..efd323cb1da 100644 --- a/etc/NEWS +++ b/etc/NEWS @@ -2989,6 +2989,15 @@ The newly created buffer will be displayed via 'display-buffer', which can be customized through the usual mechanism of 'display-buffer-alist' and friends. +** Which Function Mode + ++++ +*** Which Function Mode can now display function names on the header line. +The new user option 'which-func-display' allows choosing where the +function name is displayed. The default is 'mode' to display in the +mode line. 'header' will display in the header line. +'mode-and-header' displays in both the header line and mode line. + ** Tramp +++ diff --git a/lisp/progmodes/which-func.el b/lisp/progmodes/which-func.el index 09937a60988..631d47bb729 100644 --- a/lisp/progmodes/which-func.el +++ b/lisp/progmodes/which-func.el @@ -86,6 +86,17 @@ which-func-non-auto-modes activation of Which Function until Imenu is used for the first time." :type '(repeat (symbol :tag "Major mode"))) +(defcustom which-func-display 'mode + "Where to display the function name. + +If 'mode, display in the mode line. If 'header, display in the +header line. If 'mode-and-header, display in both." + :type '(choice (const :tag "Display in mode line" mode) + (const :tag "Display in header line" header) + (const :tag "Display in both header and mode line" + mode-and-header)) + :version "30.1") + (defcustom which-func-maxout 500000 "Don't automatically compute the Imenu menu if buffer is this big or bigger. Zero means compute the Imenu menu regardless of size. @@ -184,17 +195,35 @@ which-func-current ;;;###autoload (put 'which-func-current 'risky-local-variable t) (defvar-local which-func-mode nil - "Non-nil means display current function name in mode line. + "Non-nil means display current function name in mode or header line. This makes a difference only if variable `which-function-mode' is non-nil.") +(defvar-local which-func--use-header-line nil + "If non-nil, display the function name in the header line.") + +(defvar-local which-func--use-mode-line nil + "If non-nil, display the function name in the mode line.") + (add-hook 'after-change-major-mode-hook #'which-func-ff-hook t) (defun which-func-try-to-enable () (unless (or (not which-function-mode) (local-variable-p 'which-func-mode)) (setq which-func-mode (or (eq which-func-modes t) - (member major-mode which-func-modes))))) + (member major-mode which-func-modes))) + (setq which-func--use-mode-line + (member which-func-display '(mode mode-and-header))) + (setq which-func--use-header-line + (member which-func-display '(header mode-and-header))) + (when (and which-func-mode which-func--use-header-line) + (add-to-list 'header-line-format '("" which-func-format " "))))) + +(defun which-func--disable () + (when (and which-func-mode which-func--use-header-line) + (setq header-line-format + (delete '("" which-func-format " ") header-line-format))) + (setq which-func-mode nil)) (defun which-func-ff-hook () "`after-change-major-mode-hook' for Which Function mode. @@ -210,10 +239,10 @@ which-func-ff-hook (setq imenu--index-alist (save-excursion (funcall imenu-create-index-function)))) (imenu-unavailable - (setq which-func-mode nil)) + (which-func--disable)) (error (message "which-func-ff-hook error: %S" err) - (setq which-func-mode nil)))) + (which-func--disable)))) (defun which-func-update () "Update the Which-Function mode display in the current window." @@ -231,7 +260,7 @@ which-func-update-1 (puthash window current which-func-table) (force-mode-line-update))) (error - (setq which-func-mode nil) + (which-func--disable) (error "Error in which-func-update: %S" info)))))) (defvar which-func-update-timer nil) @@ -241,7 +270,8 @@ which-func-update-timer (add-to-list 'mode-line-misc-info '(which-function-mode ;Only display if mode is enabled. (which-func-mode ;Only display if buffer supports it. - ("" which-func-format " "))))) + (which-func--use-mode-line + ("" which-func-format " ")))))) ;; This is the name people would normally expect. ;;;###autoload -- 2.41.0