Document 'describe-symbol'

* doc/emacs/help.texi (Help Summary): Mention "C-h o".
(Name Help): Document "C-h o" and describe-symbol.

* lisp/help-fns.el (describe-symbol): Doc fix.

3 files changed, 20 insertions, 2 deletions

diff --git a/doc/emacs/help.texi b/doc/emacs/help.texi
index a9c63b91785..8b4adf947ef 100644
--- a/doc/emacs/help.texi
+++ b/doc/emacs/help.texi
@@ -126,6 +126,10 @@ Display documentation of the current major mode and minor modes
 (@code{describe-mode}).
 @item C-h n
 Display news of recent Emacs changes (@code{view-emacs-news}).
+@item C-h o @var{symbol}
+Display documentation of the Lisp symbol named @var{symbol}
+(@code{describe-symbol}).  This will show the documentation of all
+kinds of symbols: functions, variables, and faces.
 @item C-h p
 Find packages by topic keyword (@code{finder-by-keyword}).  This lists
 packages using a package menu buffer.  @xref{Packages}.
@@ -272,6 +276,14 @@ source files installed (@pxref{Hyperlinking}).
 (@code{Info-goto-emacs-command-node}).  This knows about various
 manuals, not just the Emacs manual, and finds the right one.
 
+@kindex C-h o
+@findex describe-symbol
+  @kbd{C-h o} (@code{describe-symbol}) is like @kbd{C-h f} and
+@kbd{C-h v}, but it describes any symbol, be it a function, a
+variable, or a face.  If the symbol has more than one definition, like
+it has both definition as a function and as a variable, this command
+will show the documentation of all of them, one after the other.
+
 @node Apropos
 @section Apropos
 @cindex apropos
diff --git a/etc/NEWS b/etc/NEWS
index 6608b795f8b..9793d5ee720 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -121,13 +121,16 @@ the variable `dir-locals-file' for more information.
 information about mode local overrides (defined by cedet/mode-local.el
 `define-overloadable-function' `define-mode-local-overrides').
 
++++
 ** New `display-buffer' action function `display-buffer-use-some-frame'.
 This displays the buffer in an existing frame other than the current
 frame, and allows the caller to specify a frame predicate to exclude
 frames.
 
++++
 ** New documentation command `describe-symbol'.
-Works for functions, variables, faces, etc.
+Works for functions, variables, faces, etc.  It is bound to `C-h o' by
+default.
 
 ** New user option `search-default-regexp-mode'
 specifies the default mode for I-search.
diff --git a/lisp/help-fns.el b/lisp/help-fns.el
index e810a26c5a4..41911b8709c 100644
--- a/lisp/help-fns.el
+++ b/lisp/help-fns.el
@@ -997,7 +997,10 @@ file-local variable.\n")
 ;;;###autoload
 (defun describe-symbol (symbol &optional buffer frame)
   "Display the full documentation of SYMBOL.
-Will show the info of SYMBOL as a function, variable, and/or face."
+Will show the info of SYMBOL as a function, variable, and/or face.
+Optional arguments BUFFER and FRAME specify for which buffer and
+frame to show the information about SYMBOL; they default to the
+current buffer and the selected frame, respectively."
   (interactive
    (let* ((v-or-f (symbol-at-point))
           (found (cl-some (lambda (x) (funcall (nth 1 x) v-or-f))