expression_list: expression ("," expression)* [","]
\end{verbatim}
-An expression (expression) list containing at least one comma yields a
+An expression list containing at least one comma yields a
tuple. The length of the tuple is the number of expressions in the
list. The expressions are evaluated from left to right.
\obindex{tuple}
The trailing comma is required only to create a single tuple (a.k.a. a
\emph{singleton}); it is optional in all other cases. A single
-expression (expression) without a trailing comma doesn't create a
-tuple, but rather yields the value of that expression (expression).
+expression without a trailing comma doesn't create a
+tuple, but rather yields the value of that expression.
(To create an empty tuple, use an empty pair of parentheses:
\code{()}.)
\indexii{trailing}{comma}