local tableutil = {}


--http://stackoverflow.com/questions/15706270/sort-a-table-in-lua
function tableutil.spairs(t, order)
    -- collect the keys
    local keys = {}
    for k in pairs(t) do keys[#keys + 1] = k end

    -- if order function given, sort by it by passing the table and keys a, b,
    -- otherwise just sort the keys
    if order then
        table.sort(keys, function(a, b) return order(t, a, b) end)
    else
        table.sort(keys)
    end

    -- return the iterator function
    local i = 0
    return function()
        i = i + 1
        if keys[i] then
            return keys[i], t[keys[i]]
        end
    end
end

return tableutil