UmbraSharp

a work-in-progress Lua interpreter written in C#, intended as an alternative to MoonSharp

goals

UmbraSharp will be backwards-compatible with MoonSharp syntax, and be able to compile Luau syntax (analysis will be left to luau-analyze, that is not the job of the compiler/interpreter)

it will not be a drop in replacement for MoonSharp

why

this project learns from the pain points of MoonSharp

• performance (UmbraSharp uses structs over classes, a register machine over a stack machine, and avoids allocations like the plague)
• documentation (upon completion, UmbraSharp will have detailed documentation, including on its bytecode)
• bytecode focus (UmbraSharp focuses on both source and bytecode stability)
• ownership (MoonSharp tracks and constantly checks the ownership of table/function/coroutine values. UmbraSharp is capable of handling values from other scripts, even within the same VM)

state of the project

critical

interpreter

• data types (excl. coroutines)
• instruction set
• coroutines

compiler

• lexing
• parsing
• generation of correct bytecode
• optimizing (using more of the instruction set and being smarter about its behavior)

stdlib

• lua parity
• figure out debug library
• moonsharp compat
• umbrasharp specific libraries
• yielding

non-critical

command-line interface

• rudimentary CLI

debugger

• comprehensive debugger protocol
• implementation within the interpreter
• client
• debugger protocol documentation

testing

• interpreter tests
• stdlib tests
• compiler tests

documentation

• API docs
• bytecode format
• all internal documentation

misc

• AOT support