Add/fix documentation for widget-apply

* doc/misc/widget.texi (Widget Properties): Document `widget-apply'.

* src/fns.c (Fwidget_apply): Document return value (used in many
places).

1 files changed, 6 insertions, 0 deletions

diff --git a/doc/misc/widget.texi b/doc/misc/widget.texi
index 6d94768644f..c1127a466a7 100644
--- a/doc/misc/widget.texi
+++ b/doc/misc/widget.texi
@@ -1446,6 +1446,12 @@ Non-@code{nil} if @var{widget} has a value (even @code{nil}) for
 property @var{property}.
 @end defun
 
+@defun widget-apply widget property &rest args
+Apply the value of @var{property} to @var{widget}, passing @var{args}
+as additional arguments to the function.  Return the result of that
+function call.
+@end defun
+
 Occasionally it can be useful to know which kind of widget you have,
 i.e., the name of the widget type you gave when the widget was created.