Dalbit

Dalbit(달빛) is a Luau-to-Lua transpiler, designed specifically for Lua 5.3.

TO-DOs

• Implement CLI.
• Implement basic transpilation process using darklua and full-moon.
• Implement modifiers (such as converting number literals and generalized iterations)
• Implement basic lua polyfills.
• Add tests for polyfills.
• Add tests for transpilation. (to ensure the same results in lua and luau)
• Add tests for dalbit internally.
• Add logging for dalbit internally for debug.
• convert_bit32 modifier now converts bit32.btest.
• Add comments for docs and code readability. (WIP)
• Optimize polyfill.

Installation

Using Cargo (from crates.io)

cargo install dalbit --locked

Usage

init

Initializes dalbit manifest file in the current path.

dalbit init

fetch

Fetches and updates lua polyfills.

• This polyfill can be found here.

dalbit fetch

transpile

Transpiles luau code to lua code.

dalbit transpile

clean

Cleans polyfill caches from disk.

dalbit clean

Example

dalbit.toml

input = "input.luau"
output = "output.lua"
file_extension = "lua"
target_version = "lua53"
minify = true

[modifiers]

[polyfill]
repository = "https://github.com/CavefulGames/dalbit-polyfill"
injection_path = "__polyfill__"

inputs/input.luau

local obj = { items = {1, 4, 9} }
setmetatable(obj, { __iter = function(o) return next, o.items end })

for k, v in obj do
    print(k * k)
end

outputs/output.luau

local setmetatable=require'./__polyfill__'.setmetatable local __DALBIT_getmetatable_iter=require'./__polyfill__'.__DALBIT_getmetatable_iter local type=require'./__polyfill__'.type local next=require'./__polyfill__'.next local io=nil local module=nil local package=nil local dofile=nil local loadfile=nil local load=nil local obj={items={1,4,9}}
setmetatable(obj,{__iter=function(o)return next,o.items end})do local _DALBIT_REMOVE_GENERALIZED_ITERATION_itere234e8bef135bb4c, _DALBIT_REMOVE_GENERALIZED_ITERATION_invare234e8bef135bb4c, _DALBIT_REMOVE_GENERALIZED_ITERATION_controle234e8bef135bb4c=

obj if type(_DALBIT_REMOVE_GENERALIZED_ITERATION_itere234e8bef135bb4c)=='table'then local m=__DALBIT_getmetatable_iter(_DALBIT_REMOVE_GENERALIZED_ITERATION_itere234e8bef135bb4c)if type(m)=='table'and type(m.__iter)=='function'then _DALBIT_REMOVE_GENERALIZED_ITERATION_itere234e8bef135bb4c, _DALBIT_REMOVE_GENERALIZED_ITERATION_invare234e8bef135bb4c, _DALBIT_REMOVE_GENERALIZED_ITERATION_controle234e8bef135bb4c=m.__iter(_DALBIT_REMOVE_GENERALIZED_ITERATION_itere234e8bef135bb4c)else _DALBIT_REMOVE_GENERALIZED_ITERATION_itere234e8bef135bb4c, _DALBIT_REMOVE_GENERALIZED_ITERATION_invare234e8bef135bb4c, _DALBIT_REMOVE_GENERALIZED_ITERATION_controle234e8bef135bb4c=next, _DALBIT_REMOVE_GENERALIZED_ITERATION_itere234e8bef135bb4c end end for k,v in _DALBIT_REMOVE_GENERALIZED_ITERATION_itere234e8bef135bb4c,_DALBIT_REMOVE_GENERALIZED_ITERATION_invare234e8bef135bb4c,_DALBIT_REMOVE_GENERALIZED_ITERATION_controle234e8bef135bb4c do
print(k*k)
end end

How does it work?

• Dalbit utilizes darklua and full-moon to transform lua scripts.

Why darklua-demo over darklua?

• darklua-demo is a temporary fork to work properly with dal.
• darklua-demo will be replaced by official darklua once darklua released with important features to work properly with dal.

Special Thanks

• seaofvoices/darklua - Providing important and cool lua mutating rules.
• Kampfkarren/full-moon - A lossless Lua parser.

Trivia

The name of this project, Dalbit, translates to "moonshine" in Korean.