Portability | portable |
---|---|
Maintainer | cabal-devel@haskell.org |
Defines a package identifier along with a parser and pretty printer for it.
PackageIdentifier
s consist of a name and an exact version. It also defines
a Dependency
data type. A dependency is a package name and a version
range, like "foo >= 1.2 && < 2"
.
- newtype PackageName = PackageName String
- data PackageIdentifier = PackageIdentifier {}
- type PackageId = PackageIdentifier
- newtype InstalledPackageId = InstalledPackageId String
- data Dependency = Dependency PackageName VersionRange
- thisPackageVersion :: PackageIdentifier -> Dependency
- notThisPackageVersion :: PackageIdentifier -> Dependency
- simplifyDependency :: Dependency -> Dependency
- class Package pkg where
- packageId :: pkg -> PackageIdentifier
- packageName :: Package pkg => pkg -> PackageName
- packageVersion :: Package pkg => pkg -> Version
- class Package pkg => PackageFixedDeps pkg where
- depends :: pkg -> [PackageIdentifier]
Package ids
newtype PackageName Source
data PackageIdentifier Source
The name and version of a package.
PackageIdentifier | |
|
type PackageId = PackageIdentifierSource
Type alias so we can use the shorter name PackageId.
Installed package identifiers
newtype InstalledPackageId Source
An InstalledPackageId uniquely identifies an instance of an installed package.
There can be at most one package with a given InstalledPackageId
in a package database, or overlay of databases.
Package source dependencies
data Dependency Source
Describes a dependency on a source package (API)
simplifyDependency :: Dependency -> DependencySource
Simplify the VersionRange
expression in a Dependency
.
See simplifyVersionRange
.
Package classes
Class of things that have a PackageIdentifier
Types in this class are all notions of a package. This allows us to have different types for the different phases that packages go though, from simple name/id, package description, configured or installed packages.
Not all kinds of packages can be uniquely identified by a
PackageIdentifier
. In particular, installed packages cannot, there may be
many installed instances of the same source package.
packageId :: pkg -> PackageIdentifierSource
packageName :: Package pkg => pkg -> PackageNameSource
packageVersion :: Package pkg => pkg -> VersionSource
class Package pkg => PackageFixedDeps pkg whereSource
Subclass of packages that have specific versioned dependencies.
So for example a not-yet-configured package has dependencies on version ranges, not specific versions. A configured or an already installed package depends on exact versions. Some operations or data structures (like dependency graphs) only make sense on this subclass of package types.
depends :: pkg -> [PackageIdentifier]Source