Fix (foo):n usage

extra/peg/ebnf/ebnf.factor

@@ -232,6 +232,7 @@ DEFER: 'choice'
 : ('sequence') ( -- parser )
   #! A sequence of terminals and non-terminals, including
   #! groupings of those. 
+  [
     [ 
       'ensure-not' sp ,
       'ensure' sp ,
@@ -240,6 +241,9 @@ DEFER: 'choice'
       'repeat0' sp ,
       'repeat1' sp ,
       'optional' sp , 
+    ] choice* 
+    [ dup  , ":" syntax , "a-zA-Z" range-pattern repeat1 [ >string ] action , ] seq* [ first2 <ebnf-var> ] action ,
+    ,
   ] choice* ;
 
 : 'action' ( -- parser )