# lua

a lightweight embeddable scripting language. - Lua / online / Lua Guide

Pico-8

it has some addition (+=, if() oneline, ..)
- all, add - some which can be emulated on standard lua
it lack some standard fonction (string.*n table.*) which may exist (or not in a different form).
z8lua / github - a fork of Lua that implements the PICO-8 dialect.
- to install: git clone + make => z8lua binary
- does not support require? as such difficult to use for unit-testing
Going from Lua 5.2 to PICO-8’s Lua

$ sudo apt install lua5.2   # this is the closest to PICO-8 v0.2.5g

Table can be treated as an array (list-like) or as a key-value dictionary.

-- Array
t = {1, 2, 3}

-- of dictionnary: Simple object-like table
Person = {
    name = "Alice",
    age = 25
}

-- Array
table.insert(t, 4)

-- or assign to next index
t[#t + 1] = 5

for i, v in ipairs(t) do
    print(i, v)
end

-- for dictionnary just assign the key
Person["c"] = 3
Person.d = 4  -- shorthand for t["d"]

for k, v in pairs(Person) do
    print(k, v)
end

The most widely used Lua test framework.

Syntax could be lighten with Moonscript. 🚧

$ sudo apt-get install luarocks
$ sudo apt install liblua5.2-dev  # depending on lua -v
$ sudo luarocks install busted
$ busted --version # validate

describe("math", function()
  it("adds numbers correctly", function()
    assert.is_equal(4, 2 + 2)
  end)
end)

Then run with

$ busted . # By default, it looks for *_spec.lua files in your project.

see Busted Test Explorer by Vivien Henriet

Busted error: spawn /usr/local/bin/busted ENOENT
Busted exited with code -2