Find classes available in a Module

ruby metaprogramming
joshuaxls picture joshuaxls · May 7, 2009 · Viewed 29k times · Source

I have a module MyModule. I dynamically load classes into it. How can I get a list of the classes defined within its namespace?

Example:

def load_plugins
  Dir.glob(File.dirname(__FILE__) + '/plugins/*.rb') do |f|
    MyModule.class_eval File.read(f)
  end

  # now how can I find the new classes I've loaded into MyModule?
end

I should say that each f contains something like "class Foo; end".

You can also think of it like this: in Rails, how could I programatically find all classes defined within the ActiveRecord module?

Answer

Chuck picture Chuck · May 7, 2009

Classes are accessed through constants. Classes defined within a module are listed as constants in that module. So you just need to choose the constants that refer to classes.

MyModule.constants.select {|c| MyModule.const_get(c).is_a? Class}

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