context counting

	#
	# Regular Definitions
	#
	rl rl_ws /[ \t\n\r\v]+/
	rl rl_id /[a-zA-Z_][a-zA-Z0-9_]*/
	rl rl_num /[0-9]+/

	#
	# Tokens
	#

	lex
		# Ignore whitespace.
		ignore /rl_ws/

		literal `;

		# Tokens. 
		token id /rl_id/
		token number /rl_num/
	end

	#
	# Global Data
	#

	target: int
	count: int

	#
	# Productions
	#


	def get_target 
		[number]
		{
			count = 0
			target = r1.data.atoi()
			print( 'target: ', target, '\n' )
		}

	# Arbitrary item.
	def item 
		[number]
	|	[id]

	def count_items 
		[count_inc item count_items]
	|	[count_end]

	def count_inc 
		[]
		{
			if count < target
				count = count + 1
			else
				reject
		}

	def count_end
		[]
		{
			if count < target
				reject
		}

	def counted_list 
		[get_target count_items]

	def start 
		[counted_list*]
		{
			for List: counted_list in lhs {
				match List [Count: number Items: count_items]
				print( 'num items: ', Count.data.atoi(), '\n' )

				i: int = 1
				for Item: item in Items {
					print( '  item ', i, ': ', ^Item, '\n' )
					i = i + 1
				}
			}
			print( '*** SUCCESS ***\n' )
		}
end # counting

Counting: counting = new counting()
parse counting::start( Counting )[stdin]
##### IN #####
3 1 b c 1 1 0 3 a b c
##### EXP #####
target: 3
target: 1
target: 0
target: 3
num items: 3
  item 1: 1
  item 2: b
  item 3: c
num items: 1
  item 1: 1
num items: 0
num items: 3
  item 1: a
  item 2: b
  item 3: c
*** SUCCESS ***