class Cucumber::CucumberExpressions::GeneratedExpression

def get_parameter_name(type_name, usage_by_type_name)
  count = usage_by_type_name[type_name]
  count += 1
  usage_by_type_name[type_name] = count
  count == 1 ? type_name : "#{type_name}#{count}"
end

def initialize(expression_template, parameters_types)
  @expression_template, @parameter_types = expression_template, parameters_types
end

def parameter_names
  usage_by_type_name = Hash.new(0)
  @parameter_types.map do |t|
    get_parameter_name(t.name, usage_by_type_name)
  end
end

def source
  sprintf(@expression_template, *@parameter_types.map(&:name))
end