-PreSequence ::= NamedElements => "ps"
- | PreSequence !wp ^"/" !ws e
- | PreSequence ^"->" e /ws
- | PreSequence ^"=>" ("[]"|"()"|word|Quoted) /ws
-Sequence ::= PreSequence => "psx"
+PreSequence = ps:: Elements
+ | PreSequence !wp ^"/" !ws e
+ | PreSequence ^"->" e /ws
+ | (Quoted|word) ^"::" PreSequence /ws
+ | PreSequence ^"=>" ("[]"|"()"|word|Quoted) /ws
+Sequence = psx:: PreSequence