Modified presentation of the grammar for calls to be easier to read

for both HTML and typeset renderings.  Corresponds to revision
1.53.4.8 on the r22-maint branch.

Doc/ref/ref5.tex

@@ -422,10 +422,11 @@ series of arguments:
   \production{call}
              {\token{primary} "(" [\token{argument_list} [","]] ")"}
   \production{argument_list}
-             {\token{positional_arguments} ["," \token{keyword_arguments}]
-              ["," "*" \token{expression}] ["," "**" \token{expression}]}
-  \productioncont{| \token{keyword_arguments} ["," "*" \token{expression}]
-                                               ["," "**" \token{expression}]}
+             {\token{positional_arguments} ["," \token{keyword_arguments}]}
+  \productioncont{                     ["," "*" \token{expression}]}
+  \productioncont{                     ["," "**" \token{expression}]}
+  \productioncont{| \token{keyword_arguments} ["," "*" \token{expression}]}
+  \productioncont{                    ["," "**" \token{expression}]}
   \productioncont{| "*" \token{expression} ["," "**" \token{expression}]}
   \productioncont{| "**" \token{expression}}
   \production{positional_arguments}