moonscript require on the fly loader

local moonc = "D:\\drive\\bin\\moon\\moonc.exe"
local function loader(modulename)
    local errmsg = ""
    local config = package.config
    local separator   = config:sub(3, 3)
    local placeholder = config:sub(5, 5)

    for path in (package.path .. separator):gmatch("(.-)" .. separator) do
        local path, gsubs = path, 0
        path, gsubs = path:gsub("%" .. placeholder, modulename)
        path, gsubs = path:gsub("%.lua$", ".moon")
        if gsubs > 0 then
            local touchfile, err = io.open(path, "rb")
            if touchfile then
                touchfile:close()
                local compfile, err = io.popen(moonc .. " -p " .. path .. " 2>&1", "rb")
                if not compfile then
                    error("Error compiling code from " .. path .. ": " .. tostring(err), 2)
                end
                local code = compfile:read("*all"); compfile:close()
                local finderr = code:find(path .. "\tFailed to parse:", 0, true)
                if finderr == 1 then
                    error(tostring(code), 2)
                end
                local func, err = loadstring(code, modulename)
                if not func then
                    error("Error loading module from " .. path .. ": " .. tostring(err), 2)
                end
                return func
            else
                errmsg = errmsg .. "\n\tno file '" .. path .. "' (moonloader)"
            end
        end
    end
    return errmsg
end

table.insert(package.loaders, 2, loader)