Get modules that are in a class?

Ruby
1

is it possible to find out what modules have been included inside of a
class?

2

Wayne E. Seguin wrote:

On Jul 07, 2007, at 22:00 , Aaron S. wrote:

is it possible to find out what modules have been included inside of a
class?

Yes Aaron it is, via the method “included_modules”

class Module - RDoc Documentation

What about within a class?

module TestModule
def say_something
puts “SOMETHING”
end
end

class Test
include TestModule
end

t = Test.new
puts t.included_modules

3

On Jul 07, 2007, at 22:47 , Aaron S. wrote:

end

t = Test.new
puts t.included_modules

Aaron,

you can define a method within your class to expose this like so:

module TestModule
def say_something
puts “SOMETHING”
end
end

class Test
include TestModule
def modules
self.class.included_modules
end
end

t = Test.new
puts t.modules

If you need this exposed for all classes you can expose for the
Object class:

class Object
def modules
self.class.included_modules
end
end

Does this help?
Without knowing what you’re trying to accomplish further it’s
difficult to come up with an optimal solution :slight_smile:

4

Aaron S. wrote:

t = Test.new
puts t.included_modules

Remember that when you include the module, you’re including all the
module’s methods (including Module#included_modules)

So, use self.class to get the Class object of the current instance (this
will work from the included modules also), so you should be able to do:

self.class.included_modules

And a debugging efficiency tip: use the Array#sort method with the
Module#included_modules to sort the list of included modules for easier
viewing. I use this all the time in IRB. (This also works with
Class#methods and all the like)

irb(main):001:0> YourClass.methods.sort

5

And a debugging efficiency tip: use the Array#sort method with the
Module#included_modules to sort the list of included modules for easier
viewing. I use this all the time in IRB. (This also works with
Class#methods and all the like)

irb(main):001:0> YourClass.methods.sort

Thanks. That’s perfect.

6

On Jul 07, 2007, at 23:06 , Wayne E. Seguin wrote:

class Test
If you need this exposed for all classes you can expose for the
difficult to come up with an optimal solution :slight_smile:
Aaron,

Scratch that last, it’s far easier than that:

module TestModule
def say_something
puts “SOMETHING”
end
end

class Test
include TestModule
end

t = Test.new
puts t.class.included_modules

7

On Jul 07, 2007, at 22:00 , Aaron S. wrote:

is it possible to find out what modules have been included inside of a
class?

Yes Aaron it is, via the method “included_modules”

http://www.ruby-doc.org/core/classes/Module.html#M001697

8

Hi –

On Sun, 8 Jul 2007, Travis D Warlick Jr wrote:

What about within a class?

t = Test.new
puts t.included_modules

Remember that when you include the module, you’re including all the
module’s methods (including Module#included_modules)

It’s not exactly an inclusion thing. Class objects already respond to
#included_modules, because Class inherits from Module.

So, use self.class to get the Class object of the current instance (this
will work from the included modules also), so you should be able to do:

self.class.included_modules

That will work with any object:

“”.class.included_modules

etc. It’s not dependent on your having included a module.

David

9

YourClass.methods.sort

Yes, that’s a useful trick. I use it all the time.
We can also make up many more such, with a bit of thought.

Another one I use a lot, when I think that some class is likely to
have a method with some substring in its name, is:

YourClass.methods.grep /substring/

e.g. : String.methods.grep /case/ # to find out what the String method
name to uppercase (or lowercase) a string, is called.
or
“”.methods.grep /case/

Vasudev Ram