emberian

Revisiting Tagless Final Interpreters

Tageless Final interpreters are an alternative to the traditional Algebraic Data Type (and generalized ADT) based implementation of the interpreter pattern. This document presents the Tageless Final approach with Scala, and shows how Dotty with it's recently added implicits functions makes the approach even more appealing. All examples are direct translations of their Haskell version presented in the Typed Tagless Final Interpreters: Lecture Notes (section 2).

The interpreter pattern has recently received a lot of attention in the Scala community. A lot of efforts have been invested in trying to address the biggest shortcomings of ADT/GADT based solutions: extensibility. One can first look at cats' Inject typeclass for an implementation of [Data Type à la Carte](http://www.cs.ru.nl/~W.Swierstra/Publications/DataTypesA

Update

This Gist now has its own repository on GitHub: https://github.com/Kimundi/lazy-static.rs

World building miscellany

Procedural Generation

Wikipedia: Noctis (Web page)
Noctis - Official site (Web page)
Proteus - early prototype screenshots (Blog post)
Gamasutra: The Making of Elite (Video)
The Brilliance of Dwarf Fortress
Interview with Tarn Adams (creator of Dwarf Fortress) (Slides) (Video)

	//! Chain macro in Rust
	//!
	//! A typical usage is to avoid nested match expressions.
	//!
	//! Supports:
	//! - Pattern matching
	//! - Or expressions (A \| B => ...)
	//! - Guarded statements (x if <cond> => ...)
	//! - Implicit else (requires all arms to return same type)