Improve docs of 'posn-actual-col-row' (Bug#20169)

 doc/lispref/commands.texi (Accessing Mouse): Expand documentation of
 'posn-actual-col-row'.

diff --git a/doc/lispref/ChangeLog b/doc/lispref/ChangeLog
index 1dae36ade34fba6a086f59743ba59424eeef0d2b..970d16322b36b3f1389a86d1b851c2f84778e61f 100644 (file)
--- a/doc/lispref/ChangeLog
+++ b/doc/lispref/ChangeLog
@@ -2,6 +2,8 @@
 
        * commands.texi (Event Input Misc): Fix incorrect usage of @code.
        (Bug#20174)
+       (Accessing Mouse): Expand documentation of 'posn-actual-col-row'.
+       (Bug#20169)
 
 2015-03-14  Eli Zaretskii  <eliz@gnu.org>
 

diff --git a/doc/lispref/commands.texi b/doc/lispref/commands.texi
index 4b69ed32709b11a8a97161c127972a615e165e77..6cb032c263536781d64be05b500923ee8a50676c 100644 (file)
--- a/doc/lispref/commands.texi
+++ b/doc/lispref/commands.texi
@@ -2081,7 +2081,13 @@ Return the actual row and column in @var{position}, as a cons cell
 @code{(@var{col} . @var{row})}.  The values are the actual row and
 column numbers in the window given by @var{position}.  @xref{Click
 Events}, for details.  The function returns @code{nil} if
-@var{position} does not include actual position values.
+@var{position} does not include actual position values; in that case
+@code{posn-col-row} can be used to get approximate values.
+
+Note that this function doesn't account for the visual width of
+characters on display, like the number of visual columns taken by a
+tab character or an image.  If you need the coordinates in canonical
+character units, use @code{posn-col-row} instead.
 @end defun
 
 @defun posn-string position