;;; cc-styles.el --- support for styles in CC Mode ;; Copyright (C) 1985,87,92,93,94,95,96,97,98 Free Software Foundation, Inc. ;; Authors: 1998 Barry A. Warsaw and Martin Stjernholm ;; 1992-1997 Barry A. Warsaw ;; 1987 Dave Detlefs and Stewart Clamen ;; 1985 Richard M. Stallman ;; Maintainer: bug-cc-mode@gnu.org ;; Created: 22-Apr-1997 (split from cc-mode.el) ;; Version: See cc-mode.el ;; Keywords: c languages oop ;; This file is part of GNU Emacs. ;; GNU Emacs is free software; you can redistribute it and/or modify ;; it under the terms of the GNU General Public License as published by ;; the Free Software Foundation; either version 2, or (at your option) ;; any later version. ;; GNU Emacs is distributed in the hope that it will be useful, ;; but WITHOUT ANY WARRANTY; without even the implied warranty of ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ;; GNU General Public License for more details. ;; You should have received a copy of the GNU General Public License ;; along with GNU Emacs; see the file COPYING. If not, write to the ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330, ;; Boston, MA 02111-1307, USA. ;; explicit compile-time dependencies (eval-when-compile (require 'cc-defs)) ;; Warning: don't eval-defun this constant or you'll break style inheritance. (defconst c-style-alist '(("gnu" (c-basic-offset . 2) (c-comment-only-line-offset . (0 . 0)) (c-offsets-alist . ((statement-block-intro . +) (knr-argdecl-intro . 5) (substatement-open . +) (label . 0) (statement-case-open . +) (statement-cont . +) (arglist-intro . c-lineup-arglist-intro-after-paren) (arglist-close . c-lineup-arglist) (inline-open . 0) )) (c-special-indent-hook . c-gnu-impose-minimum) (c-comment-continuation-stars . "") (c-hanging-comment-ender-p . t) ) ("k&r" (c-basic-offset . 5) (c-comment-only-line-offset . 0) (c-offsets-alist . ((statement-block-intro . +) (knr-argdecl-intro . 0) (substatement-open . 0) (label . 0) (statement-cont . +) )) ) ("bsd" (c-basic-offset . 4) (c-comment-only-line-offset . 0) (c-offsets-alist . ((statement-block-intro . +) (knr-argdecl-intro . +) (substatement-open . 0) (label . 0) (statement-cont . +) )) ) ("stroustrup" (c-basic-offset . 4) (c-comment-only-line-offset . 0) (c-offsets-alist . ((statement-block-intro . +) (substatement-open . 0) (label . 0) (statement-cont . +) )) ) ("whitesmith" (c-basic-offset . 4) (c-comment-only-line-offset . 0) (c-offsets-alist . ((statement-block-intro . +) (knr-argdecl-intro . +) (substatement-open . 0) (label . 0) (statement-cont . +) )) ) ("ellemtel" (c-basic-offset . 3) (c-comment-only-line-offset . 0) (c-hanging-braces-alist . ((substatement-open before after))) (c-offsets-alist . ((topmost-intro . 0) (topmost-intro-cont . 0) (substatement . +) (substatement-open . 0) (case-label . +) (access-label . -) (inclass . ++) (inline-open . 0) )) ) ("linux" (c-basic-offset . 8) (c-comment-only-line-offset . 0) (c-hanging-braces-alist . ((brace-list-open) (brace-entry-open) (substatement-open after) (block-close . c-snug-do-while))) (c-cleanup-list . (brace-else-brace)) (c-offsets-alist . ((statement-block-intro . +) (knr-argdecl-intro . 0) (substatement-open . 0) (label . 0) (statement-cont . +) )) ) ("python" (indent-tabs-mode . t) (fill-column . 72) (c-basic-offset . 8) (c-offsets-alist . ((substatement-open . 0) (inextern-lang . 0) (arglist-intro . +) (knr-argdecl-intro . +) )) (c-hanging-braces-alist . ((brace-list-open) (brace-list-intro) (brace-list-close) (brace-entry-open) (substatement-open after) (block-close . c-snug-do-while) )) (c-comment-continuation-stars . "") (c-hanging-comment-ender-p . nil) (fill-column . 78) ) ("java" (c-basic-offset . 4) (c-comment-only-line-offset . (0 . 0)) ;; the following preserves Javadoc starter lines (c-hanging-comment-starter-p . nil) (c-offsets-alist . ((inline-open . 0) (topmost-intro-cont . +) (statement-block-intro . +) (knr-argdecl-intro . 5) (substatement-open . +) (label . 0) (statement-case-open . +) (statement-cont . +) (arglist-intro . c-lineup-arglist-intro-after-paren) (arglist-close . c-lineup-arglist) (access-label . 0) (inher-cont . c-lineup-java-inher) (func-decl-cont . c-lineup-java-throws) )) ) ) "Styles of indentation. Elements of this alist are of the form: (STYLE-STRING [BASE-STYLE] (VARIABLE . VALUE) [(VARIABLE . VALUE) ...]) where STYLE-STRING is a short descriptive string used to select a style, VARIABLE is any Emacs variable, and VALUE is the intended value for that variable when using the selected style. Optional BASE-STYLE if present, is a string and must follow STYLE-STRING. BASE-STYLE names a style that this style inherits from. By default, all styles inherit from the \"cc-mode\" style, which is computed at run time. Style loops generate errors. Two variables are treated specially. When VARIABLE is `c-offsets-alist', the VALUE is a list containing elements of the form: (SYNTACTIC-SYMBOL . OFFSET) as described in `c-offsets-alist'. These are passed directly to `c-set-offset' so there is no need to set every syntactic symbol in your style, only those that are different from the default. When VARIABLE is `c-special-indent-hook', its VALUE is added to `c-special-indent-hook' using `add-hook'. If VALUE is a list, each element of the list is added with `add-hook'. Do not change this variable directly. Use the function `c-add-style' to add new styles or modify existing styles (it is not a good idea to modify existing styles -- you should create a new style that inherits the existing style.") ;; Functions that manipulate styles (defun c-set-style-1 (conscell) ;; Set the style for one variable (let ((attr (car conscell)) (val (cdr conscell))) (cond ;; first special variable ((eq attr 'c-offsets-alist) (mapcar (function (lambda (langentry) (let ((langelem (car langentry)) (offset (cdr langentry))) (c-set-offset langelem offset) ))) val)) ;; second special variable ((eq attr 'c-special-indent-hook) (if (listp val) (while val (add-hook 'c-special-indent-hook (car val)) (setq val (cdr val))) (add-hook 'c-special-indent-hook val))) ;; all other variables (t (set attr val))) )) (defun c-set-style-2 (style basestyles) ;; Recursively set the base style. If no base style is given, the ;; default base style is "user" (a.k.a. "cc-mode") and the recursion ;; stops. Be sure to detect loops. (let ((vars (cdr (or (assoc (downcase style) c-style-alist) (assoc (upcase style) c-style-alist) (assoc style c-style-alist) (error "Undefined style: %s" style))))) (if (not (string-equal style "user")) (let ((base (if (stringp (car vars)) (prog1 (downcase (car vars)) (setq vars (cdr vars))) "user"))) (if (memq base basestyles) (error "Style loop detected: %s in %s" base basestyles)) (c-set-style-2 base (cons base basestyles)))) (mapcar 'c-set-style-1 vars))) (defvar c-set-style-history nil) ;;;###autoload (defun c-set-style (stylename) "Set CC Mode variables to use one of several different indentation styles. STYLENAME is a string representing the desired style from the list of styles described in the variable `c-style-alist'. See that variable for details of setting up styles. The variable `c-indentation-style' always contains the buffer's current style name." (interactive (list (let ((completion-ignore-case t) (prompt (format "Which %s indentation style? " mode-name))) (completing-read prompt c-style-alist nil t (cons c-indentation-style 0) 'c-set-style-history)))) (c-initialize-builtin-style) (c-set-style-2 stylename nil) (setq c-indentation-style stylename) (c-keep-region-active)) ;;;###autoload (defun c-add-style (style descrip &optional set-p) "Adds a style to `c-style-alist', or updates an existing one. STYLE is a string identifying the style to add or update. DESCRIP is an association list describing the style and must be of the form: ([BASESTYLE] (VARIABLE . VALUE) [(VARIABLE . VALUE) ...]) See the variable `c-style-alist' for the semantics of BASESTYLE, VARIABLE and VALUE. This function also sets the current style to STYLE using `c-set-style' if the optional SET-P flag is non-nil." (interactive (let ((stylename (completing-read "Style to add: " c-style-alist nil nil nil 'c-set-style-history)) (description (eval-minibuffer "Style description: "))) (list stylename description (y-or-n-p "Set the style too? ")))) (setq style (downcase style)) (let ((s (assoc style c-style-alist))) (if s (setcdr s (copy-alist descrip)) ; replace (setq c-style-alist (cons (cons style descrip) c-style-alist)))) (and set-p (c-set-style style))) (defconst c-offsets-alist '((string . c-lineup-dont-change) (c . c-lineup-C-comments) (defun-open . 0) (defun-close . 0) (defun-block-intro . +) (class-open . 0) (class-close . 0) (inline-open . +) (inline-close . 0) (func-decl-cont . +) (knr-argdecl-intro . +) (knr-argdecl . 0) (topmost-intro . 0) (topmost-intro-cont . 0) (member-init-intro . +) (member-init-cont . 0) (inher-intro . +) (inher-cont . c-lineup-multi-inher) (block-open . 0) (block-close . 0) (brace-list-open . 0) (brace-list-close . 0) (brace-list-intro . +) (brace-list-entry . 0) (brace-entry-open . 0) (statement . 0) ;; some people might prefer ;;(statement . c-lineup-runin-statements) (statement-cont . +) ;; some people might prefer ;;(statement-cont . c-lineup-math) (statement-block-intro . +) (statement-case-intro . +) (statement-case-open . 0) (substatement . +) (substatement-open . +) (case-label . 0) (access-label . -) (label . 2) (do-while-closure . 0) (else-clause . 0) (catch-clause . 0) (comment-intro . c-lineup-comment) (arglist-intro . +) (arglist-cont . 0) (arglist-cont-nonempty . c-lineup-arglist) (arglist-close . +) (stream-op . c-lineup-streamop) (inclass . +) (cpp-macro . -1000) (cpp-macro-cont . c-lineup-dont-change) (friend . 0) (objc-method-intro . -1000) (objc-method-args-cont . c-lineup-ObjC-method-args) (objc-method-call-cont . c-lineup-ObjC-method-call) (extern-lang-open . 0) (extern-lang-close . 0) (inextern-lang . +) (namespace-open . 0) (namespace-close . 0) (innamespace . +) (template-args-cont . +) (inlambda . c-lineup-inexpr-block) (lambda-intro-cont . +) (inexpr-statement . 0) (inexpr-class . +) ) "Association list of syntactic element symbols and indentation offsets. As described below, each cons cell in this list has the form: (SYNTACTIC-SYMBOL . OFFSET) When a line is indented, CC Mode first determines the syntactic context of the line by generating a list of symbols called syntactic elements. This list can contain more than one syntactic element and the global variable `c-syntactic-context' contains the context list for the line being indented. Each element in this list is actually a cons cell of the syntactic symbol and a buffer position. This buffer position is called the relative indent point for the line. Some syntactic symbols may not have a relative indent point associated with them. After the syntactic context list for a line is generated, CC Mode calculates the absolute indentation for the line by looking at each syntactic element in the list. First, it compares the syntactic element against the SYNTACTIC-SYMBOL's in `c-offsets-alist'. When it finds a match, it adds the OFFSET to the column of the relative indent point. The sum of this calculation for each element in the syntactic list is the absolute offset for line being indented. If the syntactic element does not match any in the `c-offsets-alist', an error is generated if `c-strict-syntax-p' is non-nil, otherwise the element is ignored. Actually, OFFSET can be an integer, a function, a variable, or one of the following symbols: `+', `-', `++', `--', `*', or `/'. These latter designate positive or negative multiples of `c-basic-offset', respectively: 1, -1, 2, -2, 0.5, and -0.5. If OFFSET is a function, it is called with a single argument containing the cons of the syntactic element symbol and the relative indent point. The function should return an integer offset. OFFSET can also be a list, in which case it is recursively evaluated using the semantics described above. The first element of the list to return a non-nil value succeeds. If none of the elements returns a non-nil value, then what happends depends on the value of `c-strict-syntax-p'. When `c-strict-syntax-p' is nil, then an offset of zero is used, otherwise an error is generated. Here is the current list of valid syntactic element symbols: string -- inside multi-line string c -- inside a multi-line C style block comment defun-open -- brace that opens a function definition defun-close -- brace that closes a function definition defun-block-intro -- the first line in a top-level defun class-open -- brace that opens a class definition class-close -- brace that closes a class definition inline-open -- brace that opens an in-class inline method inline-close -- brace that closes an in-class inline method func-decl-cont -- the region between a function definition's argument list and the function opening brace (excluding K&R argument declarations). In C, you cannot put anything but whitespace and comments between them; in C++ and Java, throws declarations and other things can appear in this context. knr-argdecl-intro -- first line of a K&R C argument declaration knr-argdecl -- subsequent lines in a K&R C argument declaration topmost-intro -- the first line in a topmost construct definition topmost-intro-cont -- topmost definition continuation lines member-init-intro -- first line in a member initialization list member-init-cont -- subsequent member initialization list lines inher-intro -- first line of a multiple inheritance list inher-cont -- subsequent multiple inheritance lines block-open -- statement block open brace block-close -- statement block close brace brace-list-open -- open brace of an enum or static array list brace-list-close -- close brace of an enum or static array list brace-list-intro -- first line in an enum or static array list brace-list-entry -- subsequent lines in an enum or static array list brace-entry-open -- subsequent lines in an enum or static array list that start with an open brace. statement -- a C (or like) statement statement-cont -- a continuation of a C (or like) statement statement-block-intro -- the first line in a new statement block statement-case-intro -- the first line in a case \"block\" statement-case-open -- the first line in a case block starting with brace substatement -- the first line after an if/while/for/do/else substatement-open -- the brace that opens a substatement block case-label -- a `case' or `default' label access-label -- C++ private/protected/public access label label -- any ordinary label do-while-closure -- the `while' that ends a do/while construct else-clause -- the `else' of an if/else construct catch-clause -- the `catch' or `finally' of a try/catch construct comment-intro -- a line containing only a comment introduction arglist-intro -- the first line in an argument list arglist-cont -- subsequent argument list lines when no arguments follow on the same line as the arglist opening paren arglist-cont-nonempty -- subsequent argument list lines when at least one argument follows on the same line as the arglist opening paren arglist-close -- the solo close paren of an argument list stream-op -- lines continuing a stream operator construct inclass -- the construct is nested inside a class definition cpp-macro -- the start of a C preprocessor macro definition cpp-macro-cont -- the second and subsequent lines in a multi-line C preprocessor macro definition friend -- a C++ friend declaration objc-method-intro -- the first line of an Objective-C method definition objc-method-args-cont -- lines continuing an Objective-C method definition objc-method-call-cont -- lines continuing an Objective-C method call extern-lang-open -- brace that opens an external language block extern-lang-close -- brace that closes an external language block inextern-lang -- analogous to `inclass' syntactic symbol, but used inside, e.g. extern \"C\" constructs namespace-open -- brace that opens a C++ namespace block namespace-close -- brace that closes a C++ namespace block innamespace -- analogous to `inextern-lang' syntactic symbol, but used inside C++ namespace constructs template-args-cont -- C++ template argument list continuations inlambda -- in the header or body of a lambda function lambda-intro-cont -- continuation of the header of a lambda function inexpr-statement -- the statement is inside an expression inexpr-class -- the class is inside an expression ") (defun c-evaluate-offset (offset langelem symbol) ;; offset can be a number, a function, a variable, a list, or one of ;; the symbols + or - (cond ((eq offset '+) (setq offset c-basic-offset)) ((eq offset '-) (setq offset (- c-basic-offset))) ((eq offset '++) (setq offset (* 2 c-basic-offset))) ((eq offset '--) (setq offset (* 2 (- c-basic-offset)))) ((eq offset '*) (setq offset (/ c-basic-offset 2))) ((eq offset '/) (setq offset (/ (- c-basic-offset) 2))) ((functionp offset) (setq offset (funcall offset langelem))) ((listp offset) (setq offset (let (done) (while (and (not done) offset) (setq done (c-evaluate-offset (car offset) langelem symbol) offset (cdr offset))) (if (not done) (if c-strict-syntax-p (error "No offset found for syntactic symbol %s" symbol) 0) done)))) ((not (numberp offset)) (setq offset (symbol-value offset))) ) offset) (defun c-get-offset (langelem) ;; Get offset from LANGELEM which is a cons cell of the form: ;; (SYMBOL . RELPOS). The symbol is matched against ;; c-offsets-alist and the offset found there is either returned, ;; or added to the indentation at RELPOS. If RELPOS is nil, then ;; the offset is simply returned. (let* ((symbol (car langelem)) (relpos (cdr langelem)) (match (assq symbol c-offsets-alist)) (offset (cdr-safe match))) (if (not match) (if c-strict-syntax-p (error "No offset found for syntactic symbol %s" symbol) (setq offset 0 relpos 0)) (setq offset (c-evaluate-offset offset langelem symbol))) (+ (if (and relpos (< relpos (c-point 'bol))) (save-excursion (goto-char relpos) (current-column)) 0) (c-evaluate-offset offset langelem symbol)) )) (defvar c-read-offset-history nil) (defun c-read-offset (langelem) ;; read new offset value for LANGELEM from minibuffer. return a ;; legal value only (let* ((oldoff (cdr-safe (assq langelem c-offsets-alist))) (symname (symbol-name langelem)) (defstr (format "(default %s): " oldoff)) (errmsg (concat "Offset must be int, func, var, list, " "or [+,-,++,--,*,/] " defstr)) (prompt (concat symname " offset " defstr)) offset input interned raw) (while (not offset) (setq input (completing-read prompt obarray 'fboundp nil nil 'c-read-offset-history) offset (cond ((string-equal "" input) oldoff) ; default ((string-equal "+" input) '+) ((string-equal "-" input) '-) ((string-equal "++" input) '++) ((string-equal "--" input) '--) ((string-equal "*" input) '*) ((string-equal "/" input) '/) ((string-match "^-?[0-9]+$" input) (string-to-int input)) ;; a symbol with a function binding ((fboundp (setq interned (intern input))) interned) ;; a lambda function ((c-safe (functionp (setq raw (read input)))) raw) ;; a symbol with variable binding ((boundp interned) interned) ;; error, but don't signal one, keep trying ;; to read an input value (t (ding) (setq prompt errmsg) nil)))) offset)) ;;;###autoload (defun c-set-offset (symbol offset &optional add-p) "Change the value of a syntactic element symbol in `c-offsets-alist'. SYMBOL is the syntactic element symbol to change and OFFSET is the new offset for that syntactic element. Optional ADD says to add SYMBOL to `c-offsets-alist' if it doesn't already appear there." (interactive (let* ((langelem (intern (completing-read (concat "Syntactic symbol to change" (if current-prefix-arg " or add" "") ": ") (mapcar #'(lambda (langelem) (cons (format "%s" (car langelem)) nil)) c-offsets-alist) nil (not current-prefix-arg) ;; initial contents tries to be the last element ;; on the syntactic analysis list for the current ;; line (let* ((syntax (c-guess-basic-syntax)) (len (length syntax)) (ic (format "%s" (car (nth (1- len) syntax))))) (cons ic 0)) ))) (offset (c-read-offset langelem))) (list langelem offset current-prefix-arg))) ;; sanity check offset (or (eq offset '+) (eq offset '-) (eq offset '++) (eq offset '--) (eq offset '*) (eq offset '/) (integerp offset) (functionp offset) (listp offset) (boundp offset) (error "Offset must be int, func, var, list, or in [+,-,++,--,*,/]: %s" offset)) (let ((entry (assq symbol c-offsets-alist))) (if entry (setcdr entry offset) (if add-p (setq c-offsets-alist (cons (cons symbol offset) c-offsets-alist)) (error "%s is not a valid syntactic symbol." symbol)))) (c-keep-region-active)) (defun c-copy-tree (tree) (if (consp tree) (cons (c-copy-tree (car tree)) (c-copy-tree (cdr tree))) tree)) (defun c-initialize-builtin-style () ;; Dynamically append the default value of most variables. This is ;; crucial because future c-set-style calls will always reset the ;; variables first to the `cc-mode' style before instituting the new ;; style. Only do this once! (unless (get 'c-initialize-builtin-style 'is-run) (put 'c-initialize-builtin-style 'is-run t) (c-initialize-cc-mode) (or (assoc "cc-mode" c-style-alist) (assoc "user" c-style-alist) (progn (c-add-style "user" (mapcar (function (lambda (var) (let ((val (symbol-value var))) (cons var (c-copy-tree val))))) '(c-backslash-column c-basic-offset c-cleanup-list c-comment-only-line-offset c-electric-pound-behavior c-hanging-braces-alist c-hanging-colons-alist c-hanging-comment-starter-p c-hanging-comment-ender-p c-offsets-alist ))) (c-add-style "cc-mode" '("user")) )) (if c-style-variables-are-local-p (c-make-styles-buffer-local)))) (defun c-make-styles-buffer-local (&optional this-buf-only-p) "Make all CC Mode style variables buffer local. If you edit primarily one style of C (or C++, Objective-C, Java) code, you probably want style variables to be global. This is the default. If you edit many different styles of C (or C++, Objective-C, Java) at the same time, you probably want the CC Mode style variables to be buffer local. If you do, then you will need to set any CC Mode style variables in a hook function (e.g. off of c-mode-common-hook), instead of at the top level of your ~/.emacs file. This function makes all the CC Mode style variables buffer local. Call it after CC Mode is loaded into your Emacs environment. Conversely, set the variable `c-style-variables-are-local-p' to t in your .emacs file, before CC Mode is loaded, and this function will be automatically called when CC Mode is loaded. Optional argument, when non-nil, means use `make-local-variable' instead of `make-variable-buffer-local'." ;; style variables (let ((func (if this-buf-only-p 'make-local-variable 'make-variable-buffer-local)) (varsyms '(c-offsets-alist c-basic-offset c-file-style c-file-offsets c-comment-only-line-offset c-cleanup-list c-hanging-braces-alist c-hanging-colons-alist c-hanging-comment-starter-p c-hanging-comment-ender-p c-backslash-column c-label-minimum-indentation c-indentation-style))) (mapcar func varsyms) ;; Hooks must be handled specially (if this-buf-only-p (make-local-hook 'c-special-indent-hook) (make-variable-buffer-local 'c-special-indent-hook)) )) (provide 'cc-styles) ;;; cc-styles.el ends here