Typescript To Lua Guide

TypeScript-to-Lua Coding Guidelines

The output is Lua. For Lua runtime semantics and idioms: module pattern, coroutines, metatables, error handling, string building. Apply lua-guide; for hot-path tuning of the generated code apply lua-opinionated-guide. This skill covers only the TS→Lua transpiler boundary: what translates, how to shape TS source for clean Lua, and TSTL-specific features.

Requirements

• TSTL ≥ 1.24; TS strict mode; Lua ≥ 5.3 / LuaJIT 2.1.

Essentials

• Code organization - Favor namespaces/functions over classes for clean Lua output; Lua module idioms in lua-guide, see references/namespaces-vs-classes.md
• TSTL features - Use LuaMultiReturn, decorators when beneficial, see references/multi-return-functions.md, references/tstl-decorators.md
• Performance - Keep tables stable, cache lookups, design for Lua GC and coroutines; the JIT "why" is in lua-opinionated-guide, see references/performance-tips.md, references/coroutine-patterns.md
• Optimization - Avoid heavy TypeScript features, see references/avoiding-heavy-features.md

Gotchas

• Not all TypeScript features translate: generators, for-await-of, dynamic import(), and BigInt are unsupported or partially supported
• Translation is source-to-source; runtime semantics follow Lua, not JS: 0 and "" are truthy in Lua, falsy in JS
• Lua's table indexing (1-based, no length for holes) replaces JS arrays: pass-through types abstract this but iteration order changes
• Importing JS-only libraries silently fails at translation, only @types packages with Lua-runtime equivalents work
• tstlc is the CLI; build configs are different from tsc: sharing a tsconfig.json with web projects requires careful compilerOptions split

Progressive disclosure

• Read references/namespaces-vs-classes.md - Load when choosing code organization, namespaces, or enums for clean Lua output
• Read references/multi-return-functions.md - Load when implementing Lua-style multiple return values
• Read references/coroutine-patterns.md - Load when implementing cooperative multitasking
• Read references/lua-interop.md - Load when calling Lua code from TypeScript
• Read references/tstl-decorators.md - Load when using TSTL-specific decorators
• Read references/performance-tips.md - Load when optimizing for Lua GC/JIT or generated code is slow or bloated
• Read references/type-safety.md - Load when maintaining types across TS/Lua boundary
• Read references/avoiding-heavy-features.md - Load when transpiled output is unexpectedly large
• Read references/tsconfig.md - Load when configuring TSTL compiler options