Super Mario derivations

One of the most surprising aspects of the Nix language is that it is lazy, especially if you have never used a lazy language before. This laziness is what makes much of Nixpkgs possible, and its complexity.

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I decided to take that idea and make the attribute path a sequence of button presses in Super Mario Bros. 3. Each node in the tree is a frame of the game, and each child is a button press that produces a new frame. Game states are recursive by nature.

Farid Zakaria

This has zero practical applications, and yet, it's absolutely genius. I love this.