David Beazley – Ruckus – ddpanda's blog

Source: https://www.dabeaz.com/ruckus.html

A common project in a college Programming Languages course is to implement the core of a small programming language that has the same semantic features as found in most real-world programming languages. This typically involves:

Evaluation of Mathematical expressions
Scoped mutable variables
Higher order functions
Mutable data structures
Error handling
Memory management (garbage collection)
Types
Objects
Syntax translation (macros)

To implement a language with these features, a gentle college professor might have students use a programming language that’s well-suited for the task such as Racket. Sure, you could do that. But, maybe it all just needs to be a little bit louder–like the cacaphonous ruckus of an electric guitar played through a rusty amplifier that’s been left out in the garage a little too long. Wait, did I just say “rusty?” Oh yeah, that’s what we’re doing!

In this 4-day project course, our goal is to implement the core of a small programming language using Rust. Starting out, it doesn’t seem too bad, but we’ll enter the 9th inner circle of recursion, borrowing, and mutability hell soon enough. To make matters worse, we’ll start to doubt our prior knowledge of nice “beginner-friendly” languages like Python. Finding a way out of this mess seems possible, but it might require a beginner’s mind and a deeper sort of englightenment.