Mini-Rust

This is an attempt to implement a borrow-checker for a tiny subset of Rust.

This is an extremely rough work-in-progress. I will probably force push and re-write all commits.

No compilation actually happens. This is just parsing, type-checking, and borrow-checking.

Current Status

This works for the test cases, but a lot is missing and you should assume it's wrong in the general case.

Supported:

• shared and mutable references
• primitive types i32, bool, and ()
• enum with constant constructors
• match statements with constant or binding patterns

Not yet implemented:

• Drops - things currently never go out of scope
• Moves - everything is Copy
• Functions
• enums with constructor parameters (like in Some(x)) - they're essentially functions
• Comments - needs a custom lexer
• Showing and explaining the source of errors - needs a custom lexer
• Generics and type parameters - may need to implement part of this so that functions can use lifetimes
• Attributes - ideally implement the Copy attribute so that the default can be move

Out of scope:

• Tuples, arrays, and other primitive types
• structs
• Traits
• Closures
• Async/Await
• Macros
• Modules