context rubyhere
	rl ident_pattern /[a-zA-Z_][a-zA-Z_0-9]*/
	rl number_pattern /[0-9]+/

	lex
		ignore /[ \t\n]+/
		token id /ident_pattern/
		token number /number_pattern/
		literal '<<', '*', ',', '(', ')', '!'
	end

	HereId: str

	token rest_of_line /[^\n]*'\n'/

	lex 
		ignore /[ \t\n]+/
		token here_id
			HereData: here_data
			/ident_pattern/
			{
				# Take the text of the here_id from the input stream.
				HereId = input.pull( match_length )

				# Get the data up to the rest of the line.
				parse_stop ROL: rest_of_line(ctx)[ input ]

				# Parse the heredoc data.
				parse_stop HereData: here_data(ctx)[ input ]

				# Push the rest-of-line data back to the input stream.
				input.push( $ROL.tree )

				# Send the here_id token. Attach the heredoc data as an attribute.
				input.push( make_token( typeid<here_id> HereId HereData.tree ) )
			}
	end

	lex 
		token here_close_id 
			/ ident_pattern '\n' /
			{
				if match_text == HereId + '\n' {
					input.push( make_token( 
						typeid<here_close_id>
						input.pull( match_length ) ) )
				}
				else 
					input.push( make_token( typeid<here_line> input.pull(match_length) ) )
			}

		token here_line
			/ [^\n]* '\n' /
	end

	def here_data
		[here_line* here_close_id]

	def heredoc
		['<<' here_id]

	def primary
		[id]
	|	[number]
	|	[heredoc]

	def arglist
		[primary arglist_more*]

	def arglist_more
		[',' primary]

	def call
		[id '(' arglist? ')']

	def statement
		[primary]
	|	[call]

	token foobar /any+/

	def item
		[statement '!']
	|	[foobar]

	def start 
		[item*]
end rubyhere

cons RubyHere: rubyhere[]

parse SP: rubyhere::start(RubyHere)[ stdin ]
S: rubyhere::start = SP.tree

print_xml(S)
print('\n')