Can't figure out what's wrong

I’m reading the why’s ruby guide, and i’ve retyped a class in the guide
to use through the metaprogramming chapter. when i try to use it with
irb i get this error:
nomethoderror: undefined method '[]=] for nil:class

This forum is not affiliated to the Ruby language, Ruby on Rails framework, nor any Ruby applications discussed here.

| Privacy Policy | Terms of Service | Remote Ruby Jobs