fp-ts is a TypeScript library that provides common patterns and abstractions from other functional languages.
This repository contains examples from the fp-ts tutorial series on YouTube.
You should first install the dependencies by running yarn.
Then, you can run yarn start, which runs index.ts with ts-node-dev in watch mode.
Inside index.ts, you can import the file from the chapter that you want, and then add logs and play around with the code.
Alternatively, you can run these files with a node debugger to see what happens line by line.
Here's the list of chapters for your convenience: