---input---
rule<-("terminal"/nonterminal/[cls])*

---tokens---
'rule'        Name.Class
'<-'          Operator
'('           Punctuation
'"terminal"'  Literal.String.Double
'/'           Operator
'nonterminal' Name.Class
'/'           Operator
'['           Punctuation
'cls'         Literal.String
']'           Punctuation
')'           Punctuation
'*'           Operator
'\n'          Text.Whitespace