Ruby 2.4.0

https://www.ruby-lang.org/en/news/2016/12/25/ruby-2-4-0-released/

Unify Fixnum and Bignum into Integer

Ruby had two visible Integer classes: Fixnum and Bignum. Ruby 2.4 unifies them into Integer. All C extensions which touch the Fixnum or Bignum class need to be fixed.

RUBY_VERSION => "2.3.3"

5.class => Fixnum

(55**55).class => Bignum

RUBY_VERSION => "2.4.0"

5.class => Integer

(55**55).class => Integer