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Ruby需要全部还是全部?

require ruby

2

Sinan Taifour · 技术社区 · 17 年前

require

class A module C

class B
  include C
end

在我的特定情况下,我有一组大量相互依赖的文件,以及一个加载这些文件的加载器。举个例子,我将把文件集简化为4个文件(a.rb、b.rb、c.rb和w.rb)。以下是这些文件的列表:

# In file a.rb
class A
  @foo = []
  @foo.push("in A")

  def self.inherited(subclass)
    foo = @foo.dup
    subclass.instance_eval do
      @foo = foo
    end
  end

  def self.get_foo
    @foo
  end
end

# In file b.rb
class B < A
  include C # if C is not already defined, the following line will not get executed although B will be defined.
  @foo.push("in B")
end

# In file c.rb
module C
end

# In file w.rb
class W < B
  @foo.push("in W")
end

# In file loader.rb
files = Dir["*.rb"].reject { |f| f =~ /loader/ }
files.sort! # just for the purpose of the example, to make them load in an order that causes the problem
files.reject! { |f| require(f) rescue nil } while files.size > 0

p W.get_foo ["in A", "in B", "in W"] ,这正是我想要的。

self.inherited @foo ["in A", "in W"] .

需要

1 回复 | 直到 17 年前

1

5

Ryan McGeary 17 年前

如果一个文件依赖于另一个文件,则该文件本身应该需要依赖关系。例如, b.rb

require 'a'
require 'c'

class B < A
  include C # if C is not already defined, the following line will not get executed although B will be defined.
  @foo.push("in B")
end

和 w.rb

require 'b'

class W < B
  @foo.push("in W")
end

b a c

require