Polyglot: Lua (Part 0)

I’ve been interested in expanding my toolkit of programming languages for some time now. I would currently say that I am proficient in Java, C, and C++ and have expertise in Python. But this clearly isn’t the full range of programming languages or experiences out there. For example, I have very little knowledge of functional or embedded languages.

To encourage me to write more posts, I’m going to start documenting my experience learning different programming languages and the projects that I write with them. To start this series, I will begin with the Lua scripting language.

What Is Lua?

Lua is an “efficient, lightweight, embeddable scripting language” in active development since 1993. It claims to be fast, but most importantly the interpreter is very small at only a few 552Kb for the latest (5.4.7) binary.

Personally, this doesn’t matter a whole lot to me. Binary size and speed mean less than if I can glean a new technique or experience from using the language. But I also don’t want to waste time learning a dead language either. So every language that I learn needs to meet the following criteria:

• Must have a package manager,
• Must be able to test code,
• Must have development tooling (e.g. LSP support, code formatting, linting) and,
• (Optional) Must support static typing

Lua supports most of this primarily through community packages. luarocks is the Lua package manager. Lua does not ship with a unit testing framework by default, but the community seems to have selected luaunit as the defacto testing library. LSP and linting support is provided through the lua-language-server and code formatting is handled through stylua. However, I can’t find tooling similar to Python’s bandit to perform security audits. I believe this to be an open area of Lua library development.

Lua does not support static typing. But, given the minimal keywords and language features of Lua, the community has come up with different interpreters and programming languages that generate Lua code that implement static typing. typedlua seemed promising, as it promised to implement a type system on top of Lua (like TypeScript), but hasn’t received a commit in 5 years. ravi also seemed promising, but leverages a modified Lua VM which breaks compatibility with some Lua libraries. I would prefer the TypeScript-like approach to implementing static types to not break compatibility with existing libraries.

Learning Lua

… Will have to wait for the next post. This post took me longer than expected to compile all of my sources. As a sneak peak, I intend to release a GitHub Lua template following my other templates and another repo that is focussed on solving code kata from Rosetta Code.