almostLua

_{Lua-ish compiler for RetroStudio}

Background

RetroStudio is a Roblox game that attempts to simulate the experience of playing old Roblox. On RetroStudio, players can create their own old games, using the building and scripting tools provided by the game. The latter is better known as "block coding" because the system involves connecting blocks in a visual environment, similar to Scratch.

About almostLua

As mentioned earlier, RetroStudio uses a visual scripting system for script creation. This can get very tedious and slow, not to mention the difficulties of learning a whole new language.

The purpose of almostLua is to provide a text scripting environment that can compile Luau code into visual code, therefore saving time and making development more efficient.

almostLua does very little language processing and is moreso of a transpiler: it translates Luau statements as best as it can into visual code statements. Where it is needed, almostLua can detect features that visual scripting does not normally support, and attempt to work around it (either using stubs or simulated implementations).

almostLua has been tried by over 100 users and has seen wide use in game porting (recreating old Roblox games on RetroStudio) thanks to it being able to run pre-existing Luau code, which Roblox uses.

Screenshots

How it works

At the core of almostLua is the core processor: it takes Lua(u) tokens and converts them into blocks, then puts the blocks together in a logical executable way. Tokens are generated by the tokenizer, when given code. Additionally, almostLua users can expand the functionality of the language by modifying the modules and adding their own operators, libraries and functions.

almostLua is entirely a custom implementation of Luau written from scratch, and uses no borrowed Lua/Luau code. Not all functionality of Lua(u) has been implemented yet, therefore the project got the name "almostLua", because it's almost Lua.

Advantages

Due to being compiled, almostLua code is fast
Modular design allows for easy modification
Many hard-to-implement features backported
Convenient interface for developers

Disadvantages

Due to not running a VM, it's not as accurate
No optimization, compiled code can get messy
Not all Luau features are present