Position Paper: Goals of the Luau Type System

TL;DR

This position paper discusses the unique goals and design considerations of the Luau type system, a statically-typed extension of Lua used in Roblox, emphasizing its adaptation to a diverse developer community.

Contribution

It outlines the specific goals and challenges of designing the Luau type system tailored for Roblox's heterogeneous user base.

Findings

Luau type system supports type inference and editor assistance.

Design goals differ from traditional type systems due to community diversity.

Focus on balancing static typing with flexibility for user-generated content.

Abstract

Luau is the scripting language that powers user-generated experiences on the Roblox platform. It is a statically-typed language, based on the dynamically-typed Lua language, with type inference. These types are used for providing editor assistance in Roblox Studio, the IDE for authoring Roblox experiences. Due to Roblox's uniquely heterogeneous developer community, Luau must operate in a somewhat different fashion than a traditional statically-typed language. In this paper, we describe some of the goals of the Luau type system, focusing on where the goals differ from those of other type systems.