diff --git a/doc/emacs/help.texi b/doc/emacs/help.texi index 2513e6be271..945e12a05d2 100644 --- a/doc/emacs/help.texi +++ b/doc/emacs/help.texi @@ -317,6 +317,16 @@ by using the @kbd{M-x shortdoc} command. This will prompt you for an area of interest, e.g., @code{string}, and pop you to a buffer where many of the functions relevant for handling strings are listed. +You can also request that documentation of functions and commands +shown in @file{*Help*} buffers popped by @kbd{C-h f} includes examples +of their use. To that end, add the following to your initialization +file (@pxref{Init File}): + +@example +(add-hook 'help-fns-describe-function-functions + #'shortdoc-help-fns-examples-function) +@end example + @kindex C-h v @findex describe-variable @kbd{C-h v} (@code{describe-variable}) is like @kbd{C-h f} but diff --git a/doc/lispref/help.texi b/doc/lispref/help.texi index 59b6b6dab1d..d5e4e1c31d3 100644 --- a/doc/lispref/help.texi +++ b/doc/lispref/help.texi @@ -989,3 +989,29 @@ in the function group to insert the function into. If @var{group} doesn't exist, it will be created. If @var{section} doesn't exist, it will be added to the end of the function group. @end defun + +You can also query the examples of use of functions defined in +shortdoc groups. + +@defun shortdoc-function-examples function +This function returns all shortdoc examples for @var{function}. The +return value is an alist with items of the form +@w{@code{(@var{group} . @var{examples})}}, where @var{group} is a +documentation group where @var{function} appears, and @var{examples} +is a string with the examples of @var{function}s use as defined in +@var{group}. + +@code{shortdoc-function-examples} returns @code{nil} if @var{function} +is not a function or if it doesn't have any shortdoc examples. +@end defun + +@vindex help-fns-describe-function-functions +@defun shortdoc-help-fns-examples-function function +This function queries the registered shortdoc groups and inserts +examples of use of a given Emacs Lisp @var{function} into the current +buffer. It is suitable for addition to the +@code{help-fns-describe-function-functions} hook, in which case +examples from shortdoc of using a function will be displayed in the +@file{*Help*} buffer when the documentation of the function is +requested. +@end defun diff --git a/etc/NEWS b/etc/NEWS index 64cf11151b8..716376e1d99 100644 --- a/etc/NEWS +++ b/etc/NEWS @@ -232,6 +232,24 @@ asynchronously (which is the default behavior). *** New face 'doc-view-svg-face'. This replaces 'doc-view-svg-foreground' and 'doc-view-svg-background'. +** Shortdoc + ++++ +*** New function 'shortdoc-function-examples'. +This function returns examples of use of a given Emacs Lisp function +from the available shortdoc information. + ++++ +*** New function 'shortdoc-help-fns-examples-function'. +This function inserts into the current buffer examples of use of a +given Emacs Lisp function, which it gleans from the shortdoc +information. If you want 'describe-function' ('C-h f') to insert +examples of using the function into regular *Help* buffers, add the +following to you init file: + + (add-hook 'help-fns-describe-function-functions + #'shortdoc-help-fns-examples-function) + * New Modes and Packages in Emacs 30.1 diff --git a/lisp/emacs-lisp/shortdoc.el b/lisp/emacs-lisp/shortdoc.el index c49960c2ee6..6e3ebc7c6a2 100644 --- a/lisp/emacs-lisp/shortdoc.el +++ b/lisp/emacs-lisp/shortdoc.el @@ -1443,45 +1443,52 @@ If SAME-WINDOW, don't pop to a new window." (setq group (intern group))) (unless (assq group shortdoc--groups) (error "No such documentation group %s" group)) - (funcall (if same-window - #'pop-to-buffer-same-window - #'pop-to-buffer) - (format "*Shortdoc %s*" group)) - (let ((inhibit-read-only t) - (prev nil)) - (erase-buffer) - (shortdoc-mode) - (button-mode) - (mapc - (lambda (data) - (cond - ((stringp data) - (setq prev nil) - (unless (bobp) - (insert "\n")) - (insert (propertize - (substitute-command-keys data) - 'face 'shortdoc-heading - 'shortdoc-section t - 'outline-level 1)) - (insert (propertize - "\n\n" - 'face 'shortdoc-heading - 'shortdoc-section t))) - ;; There may be functions not yet defined in the data. - ((fboundp (car data)) - (when prev - (insert (make-separator-line) - ;; This helps with hidden outlines (bug#53981) - (propertize "\n" 'face '(:height 0)))) - (setq prev t) - (shortdoc--display-function data)))) - (cdr (assq group shortdoc--groups)))) + (let ((buf (get-buffer-create (format "*Shortdoc %s*" group)))) + (shortdoc--insert-group-in-buffer group buf) + (funcall (if same-window + #'pop-to-buffer-same-window + #'pop-to-buffer) + buf)) (goto-char (point-min)) (when function (text-property-search-forward 'shortdoc-function function t) (beginning-of-line))) +(defun shortdoc--insert-group-in-buffer (group &optional buf) + "Insert a short documentation summary for functions in GROUP in buffer BUF. +BUF defaults to the current buffer if nil or omitted." + (with-current-buffer (or buf (current-buffer)) + (let ((inhibit-read-only t) + (prev nil)) + (erase-buffer) + (shortdoc-mode) + (button-mode) + (mapc + (lambda (data) + (cond + ((stringp data) + (setq prev nil) + (unless (bobp) + (insert "\n")) + (insert (propertize + (substitute-command-keys data) + 'face 'shortdoc-heading + 'shortdoc-section t + 'outline-level 1)) + (insert (propertize + "\n\n" + 'face 'shortdoc-heading + 'shortdoc-section t))) + ;; There may be functions not yet defined in the data. + ((fboundp (car data)) + (when prev + (insert (make-separator-line) + ;; This helps with hidden outlines (bug#53981) + (propertize "\n" 'face '(:height 0)))) + (setq prev t) + (shortdoc--display-function data)))) + (cdr (assq group shortdoc--groups)))))) + ;;;###autoload (defalias 'shortdoc #'shortdoc-display-group) @@ -1521,7 +1528,8 @@ function's documentation in the Info manual")) "=>")) (single-arrow (if (char-displayable-p ?→) "→" - "->"))) + "->")) + (start-example (point))) (cl-loop for (type value) on data by #'cddr do (cl-case type @@ -1572,7 +1580,8 @@ function's documentation in the Info manual")) (:eg-result-string (insert " e.g. " double-arrow " ") (princ value (current-buffer)) - (insert "\n"))))) + (insert "\n")))) + (add-text-properties start-example (point) `(shortdoc-example ,function))) ;; Insert the arglist after doing the evals, in case that's pulled ;; in the function definition. (save-excursion @@ -1582,6 +1591,48 @@ function's documentation in the Info manual")) (insert " " (symbol-name param))) (add-face-text-property arglist-start (point) 'shortdoc-section t)))) +(defun shortdoc-function-examples (function) + "Return all shortdoc examples for FUNCTION. +The result is an alist with items of the form (GROUP . EXAMPLES), +where GROUP is a shortdoc group where FUNCTION appears, and +EXAMPLES is a string with the usage examples of FUNCTION defined +in GROUP. Return nil if FUNCTION is not a function or if it +doesn't has any shortdoc information." + (let ((groups (and (symbolp function) + (shortdoc-function-groups function))) + (examples nil)) + (mapc + (lambda (group) + (with-temp-buffer + (shortdoc--insert-group-in-buffer group) + (goto-char (point-min)) + (let ((match (text-property-search-forward + 'shortdoc-example function t))) + (push `(,group . ,(string-trim + (buffer-substring-no-properties + (prop-match-beginning match) + (prop-match-end match)))) + examples)))) + groups) + examples)) + +(defun shortdoc-help-fns-examples-function (function) + "Insert Emacs Lisp examples for FUNCTION into the current buffer. +You can add this function to the `help-fns-describe-function-functions' +hook to show examples of using FUNCTION in *Help* buffers produced +by \\[describe-function]." + (let ((examples (shortdoc-function-examples function)) + (times 0)) + (dolist (example examples) + (when (zerop times) + (if (eq (length examples) 1) + (insert "\n Example:\n\n") + (insert "\n Examples:\n\n"))) + (setq times (1+ times)) + (insert " ") + (insert (cdr example)) + (insert "\n\n")))) + (defun shortdoc-function-groups (function) "Return all shortdoc groups FUNCTION appears in." (cl-loop for group in shortdoc--groups diff --git a/test/lisp/emacs-lisp/shortdoc-tests.el b/test/lisp/emacs-lisp/shortdoc-tests.el index 516d095767f..a65a4a5ddc3 100644 --- a/test/lisp/emacs-lisp/shortdoc-tests.el +++ b/test/lisp/emacs-lisp/shortdoc-tests.el @@ -65,6 +65,16 @@ (when buf (kill-buffer buf)))))) +(ert-deftest shortdoc-function-examples-test () + "Test the extraction of usage examples of some Elisp functions." + (should (equal '((list . "(delete 2 (list 1 2 3 4))\n => (1 3 4)\n (delete \"a\" (list \"a\" \"b\" \"c\" \"d\"))\n => (\"b\" \"c\" \"d\")")) + (shortdoc-function-examples 'delete))) + (should (equal '((alist . "(assq 'foo '((foo . bar) (zot . baz)))\n => (foo . bar)") + (list . "(assq 'b '((a . 1) (b . 2)))\n => (b . 2)")) + (shortdoc-function-examples 'assq))) + (should (equal '((regexp . "(string-match-p \"^[fo]+\" \"foobar\")\n => 0")) + (shortdoc-function-examples 'string-match-p)))) + (provide 'shortdoc-tests) ;;; shortdoc-tests.el ends here diff --git a/test/lisp/eshell/em-cmpl-tests.el b/test/lisp/eshell/em-cmpl-tests.el index b60faab9114..ea907f1945d 100644 --- a/test/lisp/eshell/em-cmpl-tests.el +++ b/test/lisp/eshell/em-cmpl-tests.el @@ -261,7 +261,7 @@ See ." "Test completion of things that look like variable assignment, but aren't. For example, the second argument in \"tar --directory=dir\" looks like it could be a variable assignment, but it's not. We should -let `pcomplete-tar' handle it instead. +let `pcomplete/tar' handle it instead. See ." (with-temp-eshell