1

我需要修补一个类,但希望修补程序对某些模块是本地的。在 Ruby 中,我会这样做:

module ArrayExtension
  refine Array do
    def ===(other)
      self.include?(other)
    end
  end
end

module Foo
  using ArrayExtension
  def self.foo
    case 2
    when [1,2] then puts "bingo!"
    end
  end
end

Foo.foo          # => bingo!
puts [1,2] === 2 # => false

水晶里有类似的东西吗?

4

1 回答 1

3

所以要重新定义===你只需再次定义它。

module Foo
  def ===(other)
    self.includes?(other)
  end
end

class CustomArray(T) < Array(T)
  include Foo
end

custom_array = CustomArray(Int32).new

custom_array << 1
custom_array << 2

puts custom_array === 1 # true
puts custom_array === 2 # true
puts custom_array === 3 # false
于 2018-11-18T19:37:24.167 回答