input.lua

local module = {}

function module.puzzleInput()
    return [[light red bags contain 1 bright white bag, 2 muted yellow bags.
dark orange bags contain 3 bright white bags, 4 muted yellow bags.
bright white bags contain 1 shiny gold bag.
muted yellow bags contain 2 shiny gold bags, 9 faded blue bags.
shiny gold bags contain 1 dark olive bag, 2 vibrant plum bags.
dark olive bags contain 3 faded blue bags, 4 dotted black bags.
vibrant plum bags contain 5 faded blue bags, 6 dotted black bags.
faded blue bags contain no other bags.
dotted black bags contain no other bags.]]
end

return module

puzzle1.lua

local function split(string, match)
    local list = {}
    for i in string.gmatch(string, match) do
        table.insert(list, i)
    end
    return list
end

local function splitOnNewLines(string)
    return split(string, "([^\n]*)\n?")
end

local function splitOnContains(string)
    return split(string, '[^ contain ]*')
end

local input = require('./input')
local string = input.puzzleInput()
local bags = splitOnNewLines(string)
print(splitOnContains(bags[1])[1])