Document third argument of defvaralias.

2 files changed, 10 insertions, 3 deletions

diff --git a/etc/NEWS b/etc/NEWS
index bd29f3e3b48..b6babdcf61f 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -1517,13 +1517,16 @@ searching for an executable resp. an elisp file.
 
 ** Variable aliases have been implemented:
 
-- Macro: defvaralias ALIAS-VAR BASE-VAR
+- Macro: defvaralias ALIAS-VAR BASE-VAR [DOCSTRING]
 
 This defines the symbol ALIAS-VAR as a variable alias for symbol
 BASE-VAR.  This means that retrieving the value of ALIAS-VAR returns
 the value of BASE-VAR, and changing the value of ALIAS-VAR changes the
 value of BASE-VAR.
 
+DOCSTRING, if present, is the documentation for ALIAS-VAR; else it has
+the same documentation as BASE-VAR.
+
 - Function: indirect-variable VARIABLE
 
 This function returns the variable at the end of the chain of aliases
diff --git a/lispref/variables.texi b/lispref/variables.texi
index d7a5929bcfb..197390e0b7d 100644
--- a/lispref/variables.texi
+++ b/lispref/variables.texi
@@ -1676,11 +1676,15 @@ chosen, or because its meaning has partly changed---it can be useful
 to keep the old name as an @emph{alias} of the new one for
 compatibility.  You can do this with @code{defvaralias}.
 
-@defmac defvaralias alias-var base-var
+@defmac defvaralias alias-var base-var [docstring]
 This function defines the symbol @var{alias-var} as a variable alias
-for symbol @var{base-var}.  This means that retrieving the value of
+for symbol @var{base-var}. This means that retrieving the value of
 @var{alias-var} returns the value of @var{base-var}, and changing the
 value of @var{alias-var} changes the value of @var{base-var}.
+
+If the @var{docstring} argument is present, it specifies the documentation for
+@var{alias-var}; otherwise, it has the same documentation that @var{base-var},
+if any.
 @end defmac
 
 @defun indirect-variable variable