require 'parser'

file = '/Users/chrisseaton/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/parser-2.2.2.5/lib/parser/lexer.rb'

source_buffer = Parser::Source::Buffer.new(file)
source_buffer.read

lexer = Parser::Lexer.new('0')
lexer.source_buffer = source_buffer

loop do
  p lexer.advance
end