$ whois lua

Lua

first released in 1993 · by Roberto Ierusalimschy, Luiz Henrique de Figueiredo, Waldemar Celes

$ guessprog --inspect lua

year: 1993
paradigm: multi paradigm
family: other
memory: automatic gc
binding: dynamic
safety: strong

LUA(7)

AUTHORS: Roberto Ierusalimschy, Luiz Henrique de Figueiredo, Waldemar Celes
HISTORY: Lua was created in 1993 by Roberto Ierusalimschy, Luiz Henrique de Figueiredo and Waldemar Celes at Tecgraf, a computer graphics group at the Pontifical Catholic University of Rio de Janeiro. Brazil's trade barriers at the time made buying foreign software hard, so the group built its own configuration languages for clients such as Petrobras. Lua grew out of two of them, DEL and SOL, and since "sol" means sun in Portuguese, its successor was named "lua", the moon.
USAGE: Popular as an embedded scripting language. Lua powers game modding and scripting (World of Warcraft add-ons, and Roblox through its Luau dialect), and is used to configure and extend tools such as Neovim, Redis and nginx via OpenResty.
SEE ALSO: Lua on Wikipedia ↗

$ cat vector.lua

-- Tables are Lua's only data structure; metatables add behaviour
local Vector = {}
Vector.__index = Vector

function Vector.new(x, y)
  return setmetatable({x = x, y = y}, Vector)
end

function Vector.__add(a, b)
  return Vector.new(a.x + b.x, a.y + b.y)
end

function Vector:__tostring()
  return "(" .. self.x .. ", " .. self.y .. ")"
end

print(Vector.new(1, 2) + Vector.new(3, 4))  --> (4, 6)