##### LM #####
context undo

	lex
		ignore /[ ]+/
		literal ';', '\n'
		token id /[a-zA-Z_]+/
	end

	def item 
		[id]

	def start 
		[item* ';' '\n']

end

cons Undo: undo[]
parse Input: undo::start( Undo )[ stdin ]
print( Input )
##### IN #####
a b;
##### EXP #####
a b;