From 25be8c9040cdbe2ffe50e399a2d65eaf7759dce9 Mon Sep 17 00:00:00 2001 From: Spencer Baugh Date: Sat, 8 Jul 2023 13:54:01 -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 | 8 ++++++++ lisp/progmodes/which-func.el | 39 ++++++++++++++++++++++++++++++------ 3 files changed, 49 insertions(+), 8 deletions(-) diff --git a/doc/emacs/programs.texi b/doc/emacs/programs.texi index 953de2e4786..705e3dd358e 100644 --- a/doc/emacs/programs.texi +++ b/doc/emacs/programs.texi @@ -396,8 +396,8 @@ 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 @@ -410,6 +410,12 @@ Which Function @code{t} (which means to support all available major modes) to a list of major mode names. +@vindex which-func-display + @code{which-func-display} is a list of symbols; if it contains +@code{mode}, the function name is displayed in the mode line. If it +contains @code{header}, the function name is displayed in the header +line. By default it contains only @code{mode}. + @node Program Indent @section Indentation for Programs @cindex indentation for programs diff --git a/etc/NEWS b/etc/NEWS index 0556e8be585..f5de6974a46 100644 --- a/etc/NEWS +++ b/etc/NEWS @@ -243,6 +243,14 @@ docstring, or a comment, or (re)indents the surrounding defun if point is not in a comment or a string. It is by default bound to 'M-q' in 'prog-mode' and all its descendants. +** Which Function Mode + ++++ +*** Displaying the function name in the header line is now supported. +The new user option 'which-func-display' is a list of places to +display the function name. Add 'header' to that list to display in +the header line. + ** Tramp +++ diff --git a/lisp/progmodes/which-func.el b/lisp/progmodes/which-func.el index 09937a60988..4ea6ca1ee6f 100644 --- a/lisp/progmodes/which-func.el +++ b/lisp/progmodes/which-func.el @@ -86,6 +86,16 @@ 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. + +This should be a list of symbols. If it contains 'mode, display +in the mode line. If it contains 'header, display in the header +line." + :type '(set (const :tag "Display in mode line" mode) + (const :tag "Display in header line" 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 +194,33 @@ 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 'mode which-func-display)) + (setq which-func--use-header-line (member 'header which-func-display)) + (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 +236,10 @@ 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 +257,7 @@ 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 +267,8 @@ 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 -- 2.39.3