| Safe Haskell | Safe-Inferred |
|---|---|
| Language | Haskell2010 |
Distribution.Types.UnitId
Synopsis
- data UnitId
- unUnitId :: UnitId -> String
- mkUnitId :: String -> UnitId
- data DefUnitId
- unsafeMkDefUnitId :: UnitId -> DefUnitId
- unDefUnitId :: DefUnitId -> UnitId
- newSimpleUnitId :: ComponentId -> UnitId
- mkLegacyUnitId :: PackageId -> UnitId
- getHSLibraryName :: UnitId -> String
Documentation
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
unitIdHashisNothing. In the absence of Backpack,UnitIdis the same as aComponentId. - An indefinite, Backpack library with holes. In this case,
unitIdHashis stillNothing, but in the install, there are only interfaces, no compiled objects. - An instantiated Backpack library with all the holes
filled in.
unitIdHashis aJusta 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.
Instances
| Parsec UnitId # | The textual format for |
Defined in Distribution.Types.UnitId Methods parsec :: CabalParsing m => m UnitId # | |
| Pretty UnitId # | The textual format for |
Defined in Distribution.Types.UnitId | |
| Structured UnitId # | |
Defined in Distribution.Types.UnitId | |
| Data UnitId # | |
Defined in Distribution.Types.UnitId Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> UnitId -> c UnitId Source # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c UnitId Source # toConstr :: UnitId -> Constr Source # dataTypeOf :: UnitId -> DataType Source # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c UnitId) Source # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c UnitId) Source # gmapT :: (forall b. Data b => b -> b) -> UnitId -> UnitId Source # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> UnitId -> r Source # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> UnitId -> r Source # gmapQ :: (forall d. Data d => d -> u) -> UnitId -> [u] Source # gmapQi :: Int -> (forall d. Data d => d -> u) -> UnitId -> u Source # gmapM :: Monad m => (forall d. Data d => d -> m d) -> UnitId -> m UnitId Source # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> UnitId -> m UnitId Source # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> UnitId -> m UnitId Source # | |
| IsString UnitId # | Since: Cabal-2.0.0.2 |
Defined in Distribution.Types.UnitId Methods fromString :: String -> UnitId Source # | |
| Generic UnitId # | |
| Read UnitId # | |
| Show UnitId # | |
| Binary UnitId # | |
| NFData UnitId # | |
Defined in Distribution.Types.UnitId | |
| Eq UnitId # | |
| Ord UnitId # | |
| type Rep UnitId # | |
Defined in Distribution.Types.UnitId | |
unUnitId :: UnitId -> String #
If you need backwards compatibility, consider using display
instead, which is supported by all versions of Cabal.
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.
Instances
unsafeMkDefUnitId :: UnitId -> DefUnitId #
unDefUnitId :: DefUnitId -> UnitId #
newSimpleUnitId :: ComponentId -> UnitId #
Create a unit identity with no associated hash directly
from a ComponentId.
mkLegacyUnitId :: PackageId -> UnitId #
Make an old-style UnitId from a package identifier. Assumed to be for the public library
getHSLibraryName :: UnitId -> String #
Returns library name prefixed with HS, suitable for filenames