Trying to alias old method and create new one in ruby

Question

I'm using the following snippet to only alias the method if the method exists:

alias_method old_name, func_name if self.respond_to? func_name

How can it Error with alias_method': undefined method 'get' for class 'Sinatra::Base' (NameError) when self.respond_to? func_name returns true?

func_name = :get in this snippet

Answer 1

I found a good answer to my problem here at this link

Instead of monkey patching the original class I instead create a module and then use prepend and just call super to call the original method. I now do this:

Sinatra::Base.prepend Restman::Patches::Sinatra_Base_Patch

With the module Sinatra_Base_Patch containing the function that overwrites the original.

The example I followed is this:

class Foo
  def bar
    'Hello'
  end
end 

module FooExtensions
  def bar
    super + ' World'
  end
end

class Foo
  prepend FooExtensions # the only change to above: prepend instead of include
end

Foo.new.bar # => 'Hello World'