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dsl_fallback_methods

🛠️ Creating a Simple DSL with Fallback Methods​

method_missing shines in DSL design by capturing arbitrary method calls and mapping them to configuration or commands. This pattern simplifies building expressive internal DSLs without predefining each method.

class SimpleConfig
  def initialize
    @settings = {}
  end

  def method_missing(name, *args)
    key = name.to_s
    if key.end_with?('=')
      @settings[key.chomp('=')] = args.first
    elsif @settings.key?(key)
      @settings[key]
    else
      super
    end
  end

  def respond_to_missing?(name, include_private = false)
    true
  end
end

config = SimpleConfig.new
env = config
env.timeout = 30
env.timeout  # => 30