{-# LANGUAGE DeriveDataTypeable #-} {-# LANGUAGE DeriveGeneric #-} {-# LANGUAGE GeneralizedNewtypeDeriving #-} {-# LANGUAGE FlexibleContexts #-} module Distribution.Types.UnitId ( UnitId, unUnitId, mkUnitId , DefUnitId , unsafeMkDefUnitId , unDefUnitId , newSimpleUnitId , mkLegacyUnitId , getHSLibraryName , InstalledPackageId -- backwards compat ) where import Prelude () import Distribution.Compat.Prelude import Distribution.Utils.ShortText import qualified Distribution.Compat.ReadP as Parse import qualified Distribution.Compat.CharParsing as P import Distribution.Pretty import Distribution.Parsec.Class import Distribution.Text import Distribution.Types.ComponentId import Distribution.Types.PackageId import Text.PrettyPrint (text) -- | A unit identifier identifies a (possibly instantiated) -- package/component that can be installed the installed package -- database. There are several types of components that can be -- installed: -- -- * A traditional library with no holes, so that 'unitIdHash' -- is @Nothing@. In the absence of Backpack, 'UnitId' -- is the same as a 'ComponentId'. -- -- * An indefinite, Backpack library with holes. In this case, -- 'unitIdHash' is still @Nothing@, but in the install, -- there are only interfaces, no compiled objects. -- -- * An instantiated Backpack library with all the holes -- filled in. 'unitIdHash' is a @Just@ a hash of the -- instantiating mapping. -- -- A unit is a component plus the additional information on how the -- holes are filled in. Thus there is a one to many relationship: for a -- particular component there are many different ways of filling in the -- holes, and each different combination is a unit (and has a separate -- 'UnitId'). -- -- 'UnitId' is distinct from 'OpenUnitId', in that it is always -- installed, whereas 'OpenUnitId' are intermediate unit identities -- that arise during mixin linking, and don't necessarily correspond -- to any actually installed unit. Since the mapping is not actually -- recorded in a 'UnitId', you can't actually substitute over them -- (but you can substitute over 'OpenUnitId'). See also -- "Distribution.Backpack.FullUnitId" for a mechanism for expanding an -- instantiated 'UnitId' to retrieve its mapping. -- -- Backwards compatibility note: if you need to get the string -- representation of a UnitId to pass, e.g., as a @-package-id@ -- flag, use the 'display' function, which will work on all -- versions of Cabal. -- newtype UnitId = UnitId ShortText deriving (Generic, Read, Show, Eq, Ord, Typeable, Data, NFData) {-# DEPRECATED InstalledPackageId "Use UnitId instead. This symbol will be removed in Cabal-3.0 (est. Oct 2018)." #-} type InstalledPackageId = UnitId instance Binary UnitId -- | The textual format for 'UnitId' coincides with the format -- GHC accepts for @-package-id@. -- instance Pretty UnitId where pretty = text . unUnitId -- | The textual format for 'UnitId' coincides with the format -- GHC accepts for @-package-id@. -- instance Parsec UnitId where parsec = mkUnitId <$> P.munch1 (\c -> isAlphaNum c || c `elem` "-_.+") instance Text UnitId where parse = mkUnitId <$> Parse.munch1 (\c -> isAlphaNum c || c `elem` "-_.+") -- | If you need backwards compatibility, consider using 'display' -- instead, which is supported by all versions of Cabal. -- unUnitId :: UnitId -> String unUnitId (UnitId s) = fromShortText s mkUnitId :: String -> UnitId mkUnitId = UnitId . toShortText -- | 'mkUnitId' -- -- @since 2.0.0.2 instance IsString UnitId where fromString = mkUnitId -- | Create a unit identity with no associated hash directly -- from a 'ComponentId'. newSimpleUnitId :: ComponentId -> UnitId newSimpleUnitId = mkUnitId . unComponentId -- | Make an old-style UnitId from a package identifier. -- Assumed to be for the public library mkLegacyUnitId :: PackageId -> UnitId mkLegacyUnitId = newSimpleUnitId . mkComponentId . display -- | Returns library name prefixed with HS, suitable for filenames getHSLibraryName :: UnitId -> String getHSLibraryName uid = "HS" ++ display uid -- | A 'UnitId' for a definite package. The 'DefUnitId' invariant says -- that a 'UnitId' identified this way is definite; i.e., it has no -- unfilled holes. newtype DefUnitId = DefUnitId { unDefUnitId :: UnitId } deriving (Generic, Read, Show, Eq, Ord, Typeable, Data, Binary, NFData, Pretty, Text) -- Workaround for a GHC 8.0.1 bug, see -- https://github.com/haskell/cabal/issues/4793#issuecomment-334258288 instance Parsec DefUnitId where parsec = DefUnitId <$> parsec -- | Unsafely create a 'DefUnitId' from a 'UnitId'. Your responsibility -- is to ensure that the 'DefUnitId' invariant holds. unsafeMkDefUnitId :: UnitId -> DefUnitId unsafeMkDefUnitId = DefUnitId