Hotel Ginebra is a boutique hotel in Catalunya Square, which if you have visited Barcelona you will know is a prime location in the heart of the city. Guests can wake up in the morning to a great view of the city, but what they may not know is that the hotel has earned its place in history. It recently became the first business in the world to accept Ada, the Cardano…

In the third post in this series (part 1, part 2) on proof refinement, I'm going to show you how to properly handle bidirectionality in an elegant way. The technique we'll use is the replacement of lists and functions with a data structure called a telescope. This post will use Haskell exclusively, because of the limitations of JavaScript in presenting these things elegantly. I…