StyleGuide

Principles

• Don't use global namespaces without reasons.
• Don't make the function that have too many features.
• Use the editor that can use LDoc.
  • Visual Studio Code
  • Neovim

Syntax

Indentation

local function indent_example(query)
    for key, value in pairs(tbl) do
        if key == query then
            return { key = key, value = value}
        end
    end
end

Indent with 4 spaces. Applies automatically by editorconfig.

Variables

Local variables

local local_variable_name = 1

Use lower snake case.

Global variables

GlobalVariableName = 2

Don't use global namespaces without reasons. Use upper camel case.

Constants

local LOCAL_CONSTANT_NAME = 3
GLOBAL_CONSTANT = 3

Use upper snake case. And use Enum if constants isn't isolated.

Enum

--- @enum EnumName
ENUM_NAMES = {
    FIRST_ENUM_FIELD = 1,
    SECOND_ENUM_FIELD = 2,
    THIRD_ENUM_FIELD = 3,
}

Please write ldoc. Use upper camel case for LDoc enum name.
Use upper snake case for field name and enum name.

Function

Local Function

--- @param name string
--- @return string new_name
local function local_function(name)
    print(string.format("Hi %s!", name))
    return string.format("local %s", name)
end

Use lower snake case for function name.

Global Function

--- @param name string
--- @return string new_name
function GlobalFunction(name)
    print(string.format("Hi %s!", name))
    return string.format("global %s", name)
end

Use upper camel case for function name.

Class

Definition

--- @module luaclass
local luaclass = {}


--- @class LuaClass
--- @field name string
local LuaClass = {
    name = "lua-class",
}

--- @param name string
--- @return LuaClass
function luaclass.new(name) then
    local self = {name = name}

    setmetatable(self, {__index = LuaClass})
    return self
end

return luaclass

Use upper camel case. If you define a class that isn't in a module, write it like this:

function LuaClass.new(name) then

Inheritance

--- @module luaclass
local lualuaclass = {}


--- @class LuaLuaClass: LuaClass
--- @field bio string
local LuaLuaClass = {
    bio = "Hello world!",
}

--- @param name string
--- @param bio string
--- @return LuaLuaClass
function lualuaclass.new(name, bio)
    --- @type any
    local self = LuaClass.new(name)
    self.bio = bio

    setmetatable(self, {__index = LuaLuaClass})
    return self
end

return lualuaclass

The only one class is defined per file. The same applies to inheritance.

Methods

--- @param name string
function LuaClass:updateName(name)
    self.name = name
end

Use :
Use lower snake case.

Static Method

--- @param name string
function LuaClass.updateName(name)
    self.name = name
end

Use .
Use lower snake case for static method name.

Module

Define

--- @module "human"
local human = {}

return human

Use ** Module name and file name must be the same.

Import

local human = require("human")
local dog = require("animal.dog")

Use the require function. Don't use dofile (because it uses global namespace).

Literals

String

local hello = "Hello!"
local hi = string.format("Hi \"%s!\"", name)

USE DOUBLE QUOTES and DON'T USE SINGLE QUOTES.
If you wanna use double quotes in a string, use escaping.

Number

Boolean