class Cucumber::CucumberExpressions::Token

def self.purpose_of(token)
  case token
  when TokenType::BEGIN_OPTIONAL
    return 'optional text'
  when TokenType::END_OPTIONAL
    return 'optional text'
  when TokenType::BEGIN_PARAMETER
    return 'a parameter'
  when TokenType::END_PARAMETER
    return 'a parameter'
  when TokenType::ALTERNATION
    return 'alternation'
  else
    return ''
  end
end