diff options
Diffstat (limited to 'lisp/emacs-lisp/eldoc.el')
| -rw-r--r-- | lisp/emacs-lisp/eldoc.el | 101 |
1 files changed, 58 insertions, 43 deletions
diff --git a/lisp/emacs-lisp/eldoc.el b/lisp/emacs-lisp/eldoc.el index 2ff273ebab3..8b2538d299c 100644 --- a/lisp/emacs-lisp/eldoc.el +++ b/lisp/emacs-lisp/eldoc.el @@ -264,30 +264,43 @@ Emacs Lisp mode) that support Eldoc.") ;; so we need to be careful that errors aren't ignored. (error (message "eldoc error: %s" err)))) -;; Return a string containing the function parameter list, or 1-line -;; docstring if function is a subr and no arglist is obtainable from the -;; docstring or elsewhere. -(defun eldoc-get-fnsym-args-string (sym &optional argument-index) - (let ((args nil) - (doc nil)) +(defun eldoc-get-fnsym-args-string (sym &optional index) + "Return a string containing the parameter list of the function SYM. +If SYM is a subr and no arglist is obtainable from the docstring +or elsewhere, return a 1-line docstring. Calls the functions +`eldoc-function-argstring-format' and +`eldoc-highlight-function-argument' to format the result. The +former calls `eldoc-argument-case'; the latter gives the +function name `font-lock-function-name-face', and optionally +highlights argument number INDEX. " + (let (args doc) (cond ((not (and sym (symbolp sym) (fboundp sym)))) - ((and (eq sym (aref eldoc-last-data 0)) - (eq 'function (aref eldoc-last-data 2))) - (setq doc (aref eldoc-last-data 1))) + ((and (eq sym (aref eldoc-last-data 0)) + (eq 'function (aref eldoc-last-data 2))) + (setq doc (aref eldoc-last-data 1))) ((setq doc (help-split-fundoc (documentation sym t) sym)) (setq args (car doc)) + ;; Remove any enclosing (), since e-function-argstring adds them. (string-match "\\`[^ )]* ?" args) - (setq args (concat "(" (substring args (match-end 0)))) - (eldoc-last-data-store sym args 'function)) - (t - (setq args (eldoc-function-argstring sym)))) - (and args - argument-index - (setq doc (eldoc-highlight-function-argument sym args argument-index))) - doc)) - -;; Highlight argument INDEX in ARGS list for SYM. + (setq args (substring args (match-end 0))) + (if (string-match ")\\'" args) + (setq args (substring args 0 -1)))) + (t + (setq args (help-function-arglist sym)))) + (if args + ;; Stringify, and store before highlighting, downcasing, etc. + ;; FIXME should truncate before storing. + (eldoc-last-data-store sym (setq args (eldoc-function-argstring args)) + 'function) + (setq args doc)) ; use stored value + ;; Change case, highlight, truncate. + (if args + (eldoc-highlight-function-argument + sym (eldoc-function-argstring-format args) index)))) + (defun eldoc-highlight-function-argument (sym args index) + "Highlight argument INDEX in ARGS list for function SYM. +In the absence of INDEX, just call `eldoc-docstring-format-sym-doc'." (let ((start nil) (end 0) (argument-face 'bold)) @@ -298,7 +311,7 @@ Emacs Lisp mode) that support Eldoc.") ;; (defun NAME ARGLIST [DOCSTRING] BODY...) case? ;; The problem is there is no robust way to determine if ;; the current argument is indeed a docstring. - (while (>= index 1) + (while (and index (>= index 1)) (if (string-match "[^ ()]+" args end) (progn (setq start (match-beginning 0) @@ -438,29 +451,31 @@ Emacs Lisp mode) that support Eldoc.") (error (setq defn nil)))) defn)) -(defun eldoc-function-argstring (fn) - (eldoc-function-argstring-format (help-function-arglist fn))) - -(defun eldoc-function-argstring-format (arglist) - (cond ((not (listp arglist)) - (setq arglist nil)) - ((symbolp (car arglist)) - (setq arglist - (mapcar (function (lambda (s) - (if (memq s '(&optional &rest)) - (symbol-name s) - (funcall eldoc-argument-case - (symbol-name s))))) - arglist))) - ((stringp (car arglist)) - (setq arglist - (mapcar (function (lambda (s) - (if (member s '("&optional" "&rest")) - s - (funcall eldoc-argument-case s)))) - arglist)))) - (concat "(" (mapconcat 'identity arglist " ") ")")) - +(defun eldoc-function-argstring (arglist) + "Return ARGLIST as a string enclosed by (). +ARGLIST is either a string, or a list of strings or symbols." + (cond ((stringp arglist)) + ((not (listp arglist)) + (setq arglist nil)) + ((symbolp (car arglist)) + (setq arglist + (mapconcat (lambda (s) (symbol-name s)) + arglist " "))) + ((stringp (car arglist)) + (setq arglist + (mapconcat (lambda (s) s) + arglist " ")))) + (if arglist + (format "(%s)" arglist))) + +(defun eldoc-function-argstring-format (argstring) + "Apply `eldoc-argument-case' to each word in argstring. +The words \"&rest\", \"&optional\" are returned unchanged." + (mapconcat (lambda (s) + (if (member s '("&optional" "&rest")) + s + (funcall eldoc-argument-case s))) + (split-string argstring) " ")) ;; When point is in a sexp, the function args are not reprinted in the echo ;; area after every possible interactive command because some of them print |