bootPackageConstraints :: Args
bootPackageConstraints = stage0 ? do
    bootPkgs <- expr $ stagePackages Stage0
    let pkgs = filter (\p -> p /= compiler && isLibrary p) bootPkgs
    constraints <- expr $ forM (sort pkgs) $ \pkg -> do
        version <- pkgVersion pkg
        return (pkgName pkg ++ " == " ++ version)
    pure $ concat [ ["--constraint", c] | c <- constraints ]
bootPackageConstraints :: Args
bootPackageConstraints = stage0 ? do
    bootPkgs <- expr $ stagePackages Stage0
    let pkgs = filter (\p -> p /= compiler && isLibrary p) bootPkgs
    constraints <- expr $ forM (sort pkgs) $ \pkg -> do
        version <- pkgVersion pkg
        return (pkgName pkg ++ " == " ++ version)
    pure $ concat [ ["--constraint", c] | c <- constraints ]
bootPackageConstraints = stage0 ? do
    bootPkgs <- expr $ stagePackages Stage0
    let pkgs = filter (\p -> p /= compiler && isLibrary p) bootPkgs
    constraints <- expr $ forM (sort pkgs) $ \pkg -> do
        version <- pkgVersion pkg
        return (pkgName pkg ++ " == " ++ version)
    pure $ concat [ ["--constraint", c] | c <- constraints ]