Is it possible to make an alias for a module in Ruby?

Question

In Python, you can set an alias for a module with 'as':

import mymodule as mm 

But I can't seem to find an equivalent for ruby. I know that you can include rather than require a module, but this risks namespace collisions. Is there any equivalent to Python module aliases?

Answer 1

Modules in Ruby aren't really that special, so you can just assign them to another constant:

[4] (pry) main: 0> module TestModule [4] (pry) main: 0*   def self.foo [4] (pry) main: 0*     "test" [4] (pry) main: 0*   end   [4] (pry) main: 0* end   => nil [5] (pry) main: 0> tm = TestModule => TestModule [6] (pry) main: 0> tm.foo => "test" 

Answer 2

Michael's answer seems to solve your question... still, I read the question a bit differently and discovered something really nice that I thought worth sharing.

I understood your question as: "What do I do if I want to require two modules of the same name?", that is, how could I alias them if requiring both would result in a namespace clash? Because, as far as my understanding of Python's 'import ... as ...' goes, it also solves those kinds of problems. An example in Ruby:

#file a.rb module A   def self.greet     puts 'A'   end end  #file b.rb module A   def self.greet     puts 'other A'   end end 

Now if I would do this in a third file:

require_relative 'a' require_relative 'b'  A.greet # => other A 

the first A would be completely overridden by the A in b.rb. Using Michael's trick also won't help:

require_relative 'a' TMP_A = A A.greet # => A TMP_A.greet # => A require_relative 'b' TMP_A2 = A A.greet # => other A TMP_A2.greet # => other A TMP_A.greet # => other A :( 

Too bad. Then I thought, well, in Ruby there's the ubiquitous dup for making a clone of basically everything and without too much hope I just typed this and reran the program:

require_relative 'a' TMP_A = A.dup A.greet # => A TMP_A.greet # => A require_relative 'b' TMP_A2 = A A.greet # => other A TMP_A2.greet # => other A TMP_A.greet # => A :P 

That totally made my day, hope you guys appreciate it as much as well. Now that I think about it, it makes sense - a module is an object like any other after all, so why shouldn't dup work?