ActiveSupport 中的 Configurable

ActiveSupport::Configurable 为类提供一个 config 的方法，通过它可以进行各种配置。

class YourClass
  include ActiveSupport::Configurable
end

YourClass.config.a_option = 'value'

YourClass.config.a_option
=> "value"

它还提供了一个更实用的 configure 方法

class YourClass
  include ActiveSupport::Configurable
end

YourClass.configure do |config|
  config.a_option = 'value'
end

YourClass.config.a_option
=> "value"

它还提供了一个类方法 config_accessor，它可以指定默认值。

class YourClass
  include ActiveSupport::Configurable

  config_accessor :a_option do
    'value'
  end
end

YourClass.config.a_option
=> "value"
YourClass.a_option
=> "value"
YourClass.a_option = "new_value"
=> "new_value"

如果不想使用 ActiveSupport，自己写一个类似的接口也是很方便的 https://qichunren.github.io/dev_tips/configure_api_pattern.html

See doc