NameError: uninitialized constant

I recently opened up pry, ran this:

but got this:

Not greatly helpful.

It turned out that, despite adding it to my Gemfile and running

I still needed to require the file in pry.

However, the name of the file isn’t obvious if it’s not your own gem. E.g.

Eventually it seemed to be correct:

but this didn’t work:

but by looking at the gem file name via:

I eventually used:

which worked. E.g.

This all seems a lot of guess work.

What I’d like to see (and I’m sure there must be a way of doing this but Google’ing and searching StackOverflow has not turned anything up) is something like this: