ruby – 显示错误的模式

module MyLib
  VERSION = "0.1.1"
  ERROR = [
    "You can either give one arg and a block or two args, not both.",
    "Yadda yadda..."
  ]
end

然后在我的代码中的某个地方：

def my_method(*args, &blk)
  raise(ArgumentError, MyLib::ERROR[0]) if (...condition snipped...)
end

有没有更好的方法来定义错误消息？

module MyLib
  class FooError < ArgumentError
    def to_s
      "You can either give one arg and a block or two args, not both.",
    end
  end
end

现在,如果你举起它：

raise MyLib::FooError
MyLib::FooError: You can either give one arg and a block or two args, not both.
    from (irb):46

如果你想处理它：

rescue MyLib::FooError