ruby - Rubinius 在哪里实现了 mixin？

Question

Rubinius 源代码中负责包含模块的代码在哪里？（具体而言，将模块放置为对象类的超类。）

Answer 1

如果您查看 的文档Module#include，您会发现它委托给Module#append_features：

Module.append_features以相反的顺序调用每个参数。

Module#append_features反过来，文档（非常简要地）描述了默认的 Ruby 混合算法是如何工作的：

当这个模块包含在另一个模块中时，Ruby 会调用append_features这个模块，将接收模块传递给mod. Ruby 的默认实现是将此模块的常量、方法和模块变量添加到mod如果该模块尚未添加到mod它的祖先之一。另请参阅Module#include。

如果你查看Rubinius 源代码Module#append_features，你会发现它是一个别名：Module#include_into

# Called when this Module is being included in another Module.
# This may be overridden for custom behaviour. The default
# is to add constants, instance methods and module variables
# of this Module and all Modules that this one includes to +klass+.
#
# See also #include.
#
alias_method :append_features, :include_into

所以，最后，Module#include_into是真正的交易：

# Add all constants, instance methods and module variables
# of this Module and all Modules that this one includes to +klass+
#
# This method is aliased as append_features as the default implementation
# for that method. Kernel#extend calls this method directly through
# Module#extend_object, because Kernel#extend should not use append_features.
def include_into(klass)
  ...

您的具体问题：

正是将模块作为对象类的超类

在这个循环中回答：

k = klass.direct_superclass
while k
  if k.kind_of? Rubinius::IncludedModule
    # Oh, we found it.
    if k == mod
      # ok, if we're still within the directly included modules
      # of klass, then put future things after mod, not at the
      # beginning.
      insert_at = k unless superclass_seen
      add = false
      break
    end
  else
    superclass_seen = true
  end

  k = k.direct_superclass
end

注意insert_at。