lex
	ignore /space+/
	literal `* `( `)
	token id /[a-zA-Z_]+/
end

def item 
	[id]
|	[`( item* `)]

def item2
	[id]
|	[`( item2* `)]

def start 
	[item*]

StartParser1: parser<start> = new parser<start>()
StartParser2: parser<start> = new parser<start>()

parse Item2: item2 "b

# Success.
send StartParser1
	"a [Item2] c d\n" eos

# Failure.
send_tree StartParser2
	"a [Item2] c d\n" eos

print [@StartParser1->tree]
print [@StartParser2->tree "\n"]
######### EXP #########
a b
 c d
NIL