getCreaturesInRetangleArea(pos_init, pos_final)

function getCreaturesInRetangleArea(pos_init, pos_final)
    --[[
    getCreaturesInRetangleArea(pos_init, pos_final)

    * pos_init(1) = ponta esquerda superior da area
    * pos_final(2) = ponta direita inferior da area
    @return table -> lista de uids das criaturas na area
    ]]

    -- private
    local function isPosition(pos)
        return (type(pos) == "table" and type(pos.x) == "number" and type(pos.y) == "number" and type(pos.z) == "number")
    end


    local creatureList = {}
    local error = nil

    if not (isPosition(pos_init) and isPosition(pos_final)) then
        error = debug.traceback("Invalid parameters, expected positions")
    end

    if not (pos_init.x <= pos_final.x and pos_init.y <= pos_init.y and pos_init.z == pos_final.z) then
        error = debug.traceback("can't form a retangle with positions")
    end

    if error then
        print(error)
        return false
    end

    for x = pos_init.x, pos_final.x do
        for y = pos_init.y, pos_final.y do
            local pos = {x = x, y = y, z = pos_init.z}
            for stack = 0, getTileInfo(pos).things do
                pos.stackpos = stack
                local thing = getThingfromPos(pos)
                if isCreature(thing.uid) then
                    table.insert(creatureList, thing.uid)
                end
            end
        end
    end

    return creatureList
end