psy ::= Elements => "ps"
| psy !wp ^"/" !ws e
| psy ^"->" e /ws
+ | psy "=>" ("[]"|"()"|word|Quoted) /ws => goo
Sequence ::= Quoted => "qprod"
- > psy => "psx"
- | psy "=>" ^"[]" /ws
- | psy ^"=>" ("()"|word|Quoted) /ws
+ > psy => "psx"
ec ::= ~[\-\]\\]
| escaped