+mkModuleNameFS :: FastString -> ModuleName
+mkModuleNameFS s = ModuleName s
+
+-- | Returns the string version of the module name, with dots replaced by slashes
+moduleNameSlashes :: ModuleName -> String
+moduleNameSlashes = dots_to_slashes . moduleNameString
+ where dots_to_slashes = map (\c -> if c == '.' then pathSeparator else c)
+\end{code}
+
+%************************************************************************
+%* *
+\subsection{A fully qualified module}
+%* *
+%************************************************************************
+
+\begin{code}
+-- | A Module is a pair of a 'PackageId' and a 'ModuleName'.
+data Module = Module {
+ modulePackageId :: !PackageId, -- pkg-1.0
+ moduleName :: !ModuleName -- A.B.C
+ }
+ deriving (Eq, Ord)
+
+instance Uniquable Module where
+ getUnique (Module p n) = getUnique (packageIdFS p `appendFS` moduleNameFS n)
+
+instance Outputable Module where
+ ppr = pprModule
+
+instance Binary Module where
+ put_ bh (Module p n) = put_ bh p >> put_ bh n
+ get bh = do p <- get bh; n <- get bh; return (Module p n)
+
+-- | This gives a stable ordering, as opposed to the Ord instance which
+-- gives an ordering based on the 'Unique's of the components, which may
+-- not be stable from run to run of the compiler.
+stableModuleCmp :: Module -> Module -> Ordering
+stableModuleCmp (Module p1 n1) (Module p2 n2)
+ = (p1 `stablePackageIdCmp` p2) `thenCmp`
+ (n1 `stableModuleNameCmp` n2)
+
+mkModule :: PackageId -> ModuleName -> Module
+mkModule = Module
+
+pprModule :: Module -> SDoc
+pprModule mod@(Module p n) = pprPackagePrefix p mod <> pprModuleName n
+
+pprPackagePrefix :: PackageId -> Module -> PprStyle -> Pretty.Doc
+pprPackagePrefix p mod = getPprStyle doc
+ where
+ doc sty
+ | codeStyle sty =
+ if p == mainPackageId
+ then empty -- never qualify the main package in code
+ else ftext (zEncodeFS (packageIdFS p)) <> char '_'
+ | qualModule sty mod = ftext (packageIdFS (modulePackageId mod)) <> char ':'
+ -- the PrintUnqualified tells us which modules have to
+ -- be qualified with package names
+ | otherwise = empty
+\end{code}
+
+%************************************************************************
+%* *
+\subsection{PackageId}
+%* *
+%************************************************************************
+
+\begin{code}
+-- | Essentially just a string identifying a package, including the version: e.g. parsec-1.0
+newtype PackageId = PId FastString deriving( Eq )
+ -- here to avoid module loops with PackageConfig
+
+instance Uniquable PackageId where
+ getUnique pid = getUnique (packageIdFS pid)
+
+-- Note: *not* a stable lexicographic ordering, a faster unique-based
+-- ordering.
+instance Ord PackageId where
+ nm1 `compare` nm2 = getUnique nm1 `compare` getUnique nm2
+
+stablePackageIdCmp :: PackageId -> PackageId -> Ordering
+-- ^ Compares package ids lexically, rather than by their 'Unique's
+stablePackageIdCmp p1 p2 = packageIdFS p1 `compare` packageIdFS p2
+
+instance Outputable PackageId where
+ ppr pid = text (packageIdString pid)
+
+instance Binary PackageId where
+ put_ bh pid = put_ bh (packageIdFS pid)
+ get bh = do { fs <- get bh; return (fsToPackageId fs) }
+
+fsToPackageId :: FastString -> PackageId
+fsToPackageId = PId
+
+packageIdFS :: PackageId -> FastString
+packageIdFS (PId fs) = fs
+
+stringToPackageId :: String -> PackageId
+stringToPackageId = fsToPackageId . mkFastString
+
+packageIdString :: PackageId -> String
+packageIdString = unpackFS . packageIdFS
+
+
+-- -----------------------------------------------------------------------------
+-- $wired_in_packages
+-- Certain packages are known to the compiler, in that we know about certain
+-- entities that reside in these packages, and the compiler needs to
+-- declare static Modules and Names that refer to these packages. Hence
+-- the wired-in packages can't include version numbers, since we don't want
+-- to bake the version numbers of these packages into GHC.
+--
+-- So here's the plan. Wired-in packages are still versioned as
+-- normal in the packages database, and you can still have multiple
+-- versions of them installed. However, for each invocation of GHC,
+-- only a single instance of each wired-in package will be recognised
+-- (the desired one is selected via @-package@\/@-hide-package@), and GHC
+-- will use the unversioned 'PackageId' below when referring to it,
+-- including in .hi files and object file symbols. Unselected
+-- versions of wired-in packages will be ignored, as will any other
+-- package that depends directly or indirectly on it (much as if you
+-- had used @-ignore-package@).
+
+-- Make sure you change 'Packages.findWiredInPackages' if you add an entry here
+
+integerPackageId, primPackageId,
+ basePackageId, rtsPackageId, haskell98PackageId, sybPackageId,
+ thPackageId, dphSeqPackageId, dphParPackageId,
+ mainPackageId :: PackageId
+primPackageId = fsToPackageId (fsLit "ghc-prim")
+integerPackageId = fsToPackageId (fsLit "integer")
+basePackageId = fsToPackageId (fsLit "base")
+rtsPackageId = fsToPackageId (fsLit "rts")
+haskell98PackageId = fsToPackageId (fsLit "haskell98")
+sybPackageId = fsToPackageId (fsLit "syb")
+thPackageId = fsToPackageId (fsLit "template-haskell")
+dphSeqPackageId = fsToPackageId (fsLit "dph-seq")
+dphParPackageId = fsToPackageId (fsLit "dph-par")
+
+-- | This is the package Id for the current program. It is the default
+-- package Id if you don't specify a package name. We don't add this prefix
+-- to symbol names, since there can be only one main package per program.
+mainPackageId = fsToPackageId (fsLit "main")