Distribution.Package

Defines a package identifier along with a parser and pretty printer for it. PackageIdentifiers 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".

Package ids

newtype PackageName

Constructors

PackageName

Fields

unPackageName :: String

Instances

Eq PackageName

Data PackageName

Ord PackageName

Read PackageName

Show PackageName

Generic PackageName

Binary PackageName

NFData PackageName

Text PackageName

Typeable * PackageName

type Rep PackageName

data PackageIdentifier

The name and version of a package.

Constructors

PackageIdentifier

Fields

pkgName :: PackageName

The name of this package, eg. foo

pkgVersion :: Version

the version of this package, eg 1.2

Instances

Eq PackageIdentifier

Data PackageIdentifier

Ord PackageIdentifier

Read PackageIdentifier

Show PackageIdentifier

Generic PackageIdentifier

Binary PackageIdentifier

NFData PackageIdentifier

Text PackageIdentifier

Package PackageIdentifier

Typeable * PackageIdentifier

type Rep PackageIdentifier

type PackageId = PackageIdentifier

Type alias so we can use the shorter name PackageId.

Installed package identifiers

newtype InstalledPackageId

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.

Constructors

InstalledPackageId String

Instances

Eq InstalledPackageId

Data InstalledPackageId

Ord InstalledPackageId

Read InstalledPackageId

Show InstalledPackageId

Generic InstalledPackageId

Binary InstalledPackageId

Text InstalledPackageId

Typeable * InstalledPackageId

type Rep InstalledPackageId

Package keys (used for linker symbols and library name)

data PackageKey

A PackageKey is the notion of "package ID" which is visible to the compiler. Why is this not a PackageId? The PackageId is a user-visible concept written explicity in Cabal files; on the other hand, a PackageKey may contain, for example, information about the transitive dependency tree of a package. Why is this not an InstalledPackageId? A PackageKey affects the ABI because it is used for linker symbols; however, an InstalledPackageId can be used to distinguish two ABI-compatible versions of a library.

The key is defined to be a 128-bit MD5 hash, separated into two 64-bit components (the most significant component coming first) which are individually base-62 encoded (A-Z, a-z, 0-9).

     key         ::= hash64 hash64
     hash64      ::= [A-Za-z0-9]{11}

The string that is hashed is specified as raw_key:

     raw_key     ::= package_id "n"
                     holes_nl
                     depends_nl
     package_id  ::= package_name "-" package_version
     holes_nl    ::= ""
                   | hole_inst "n" holes_nl
     hole_inst   ::= modulename " " key ":" modulename
     depends_nl  ::= ""
                   | depend "n" depends_nl
     depend      ::= key

The holes list MUST be sorted by the first modulename; the depends list MUST be sorted by the key. holes describes the backing implementations of all holes in the package; depends describes all of the build-depends of a package. A package key MAY be used in holes even if it is not mentioned in depends: depends contains STRICTLY packages which are textually mentioned in the package description.

The trailing newline is MANDATORY.

There is also a variant of package key which is prefixed by a informational string. This key MUST NOT be used in the computation of the hash proper, but it is useful for human-readable consumption.

     infokey     ::= infostring "_" key
     infostring  ::= [A-Za-z0-9-]+

For example, Cabal provides a key with the first five characters of the package name for linker symbols.

Constructors

PackageKey !String !Word64 !Word64

Modern package key which is a hash of the PackageId and the transitive dependency key. Manually inline it here so we can get the instances we need. Also contains a short informative string

OldPackageKey !PackageId

Old-style package key which is just a PackageId. Required because old versions of GHC assume that the sourcePackageId recorded for an installed package coincides with the package key it was compiled with.

Instances

Eq PackageKey

Data PackageKey

Ord PackageKey

Read PackageKey

Show PackageKey

Generic PackageKey

Binary PackageKey

NFData PackageKey

Text PackageKey

Typeable * PackageKey

type Rep PackageKey

mkPackageKey :: Bool -> PackageId -> [PackageKey] -> [(ModuleName, (PackageKey, ModuleName))] -> PackageKey

Generates a PackageKey from a PackageId, sorted package keys of the immediate dependencies.

packageKeyHash :: PackageKey -> String

packageKeyLibraryName :: PackageId -> PackageKey -> String

Package source dependencies

data Dependency

Describes a dependency on a source package (API)

Constructors

Dependency PackageName VersionRange

Instances

Eq Dependency

Data Dependency

Read Dependency

Show Dependency

Generic Dependency

Binary Dependency

Text Dependency

Typeable * Dependency

type Rep Dependency

thisPackageVersion :: PackageIdentifier -> Dependency

notThisPackageVersion :: PackageIdentifier -> Dependency

simplifyDependency :: Dependency -> Dependency

Simplify the VersionRange expression in a Dependency. See simplifyVersionRange.

Package classes

class Package pkg where

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.

Methods

packageId :: pkg -> PackageIdentifier

Instances

Package PackageIdentifier

Package GenericPackageDescription

Package PackageDescription

Package (InstalledPackageInfo_ str)

packageName :: Package pkg => pkg -> PackageName

packageVersion :: Package pkg => pkg -> Version

class Package pkg => PackageFixedDeps pkg where

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.

Methods

depends :: pkg -> [PackageIdentifier]

class Package pkg => PackageInstalled pkg where

Class of installed packages.

The primary data type which is an instance of this package is InstalledPackageInfo, but when we are doing install plans in Cabal install we may have other, installed package-like things which contain more metadata. Installed packages have exact dependencies installedDepends.

Methods

installedPackageId :: pkg -> InstalledPackageId

installedDepends :: pkg -> [InstalledPackageId]

Instances

PackageInstalled (InstalledPackageInfo_ str)