packageUrl :: PackageName -> VersionNumber -> String
packageUrl packagename versionnumber = concat [
    "hackage.haskell.org/packages/archive/",
    packagename,
    "/",
    showVersion versionnumber,
    "/",
    packageIdentifier packagename versionnumber,
    ".tar.gz"]
packageUrl :: PackageName -> VersionNumber -> String
packageUrl packagename versionnumber = concat [
    "hackage.haskell.org/packages/archive/",
    packagename,
    "/",
    showVersion versionnumber,
    "/",
    packageIdentifier packagename versionnumber,
    ".tar.gz"]
packageUrl packagename versionnumber = concat [
    "hackage.haskell.org/packages/archive/",
    packagename,
    "/",
    showVersion versionnumber,
    "/",
    packageIdentifier packagename versionnumber,
    ".tar.gz"]