Checking if a variable is an integer

Question

Does Rails 3 or Ruby have a built-in way to check if a variable is an integer?

For example,

1.is_an_int #=> true
\"dadadad@asdasd.net\".is_an_int          


        

Answer 1

To capitalize on the answer of Alex D, using refinements:

module CoreExtensions
  module Integerable
    refine String do
      def integer?
        Integer(self)
      rescue ArgumentError
        false
      else
        true
      end
    end
  end
end

Later, in you class:

require 'core_ext/string/integerable'

class MyClass
  using CoreExtensions::Integerable

  def method
    'my_string'.integer?
  end
end