    {-# LANGUAGE CPP #-}
    {-# LANGUAGE DeriveDataTypeable #-}
    {-# LANGUAGE DeriveFunctor #-}
    {-# LANGUAGE DeriveGeneric #-}
    {-# LANGUAGE FlexibleContexts #-}
    {-# LANGUAGE RankNTypes #-}

    -----------------------------------------------------------------------------
    -- |
    -- Module      :  Distribution.Simple.InstallDirs
    -- Copyright   :  Isaac Jones 2003-2004
    -- License     :  BSD3
    --
    -- Maintainer  :  cabal-devel@haskell.org
    -- Portability :  portable
    --
    -- This manages everything to do with where files get installed (though does
    -- not get involved with actually doing any installation). It provides an
    -- 'InstallDirs' type which is a set of directories for where to install
    -- things. It also handles the fact that we use templates in these install
    -- dirs. For example most install dirs are relative to some @$prefix@ and by
    -- changing the prefix all other dirs still end up changed appropriately. So it
    -- provides a 'PathTemplate' type and functions for substituting for these
    -- templates.

    module Distribution.Simple.InstallDirs (
            InstallDirs(..),
            InstallDirTemplates,
            defaultInstallDirs,
            defaultInstallDirs',
            combineInstallDirs,
            absoluteInstallDirs,
            CopyDest(..),
            prefixRelativeInstallDirs,
            substituteInstallDirTemplates,

            PathTemplate,
            PathTemplateVariable(..),
            PathTemplateEnv,
            toPathTemplate,
            fromPathTemplate,
            combinePathTemplate,
            substPathTemplate,
            initialPathTemplateEnv,
            platformTemplateEnv,
            compilerTemplateEnv,
            packageTemplateEnv,
            abiTemplateEnv,
            installDirsTemplateEnv,
      ) where

    import Prelude ()
    import Distribution.Compat.Prelude

    import Distribution.Compat.Environment (lookupEnv)
    import Distribution.Pretty
    import Distribution.Package
    import Distribution.System
    import Distribution.Compiler
    import Distribution.Simple.InstallDirs.Internal

    import System.Directory (getAppUserDataDirectory)
    import System.FilePath
      ( (</>), isPathSeparator
      , pathSeparator, dropDrive
      , takeDirectory )

    #ifdef mingw32_HOST_OS
    import qualified Prelude
    import Foreign
    import Foreign.C
    #endif

    -- ---------------------------------------------------------------------------
    -- Installation directories

    -- | The directories where we will install files for packages.
    --
    -- We have several different directories for different types of files since
    -- many systems have conventions whereby different types of files in a package
    -- are installed in different directories. This is particularly the case on
    -- Unix style systems.
    --
    data InstallDirs dir = InstallDirs {
            forall dir. InstallDirs dir -> dir
    prefix       :: dir,
            forall dir. InstallDirs dir -> dir
    bindir       :: dir,
            forall dir. InstallDirs dir -> dir
    libdir       :: dir,
            forall dir. InstallDirs dir -> dir
    libsubdir    :: dir,
            forall dir. InstallDirs dir -> dir
    dynlibdir    :: dir,
            forall dir. InstallDirs dir -> dir
    flibdir      :: dir, -- ^ foreign libraries
            forall dir. InstallDirs dir -> dir
    libexecdir   :: dir,
            forall dir. InstallDirs dir -> dir
    libexecsubdir:: dir,
            forall dir. InstallDirs dir -> dir
    includedir   :: dir,
            forall dir. InstallDirs dir -> dir
    datadir      :: dir,
            forall dir. InstallDirs dir -> dir
    datasubdir   :: dir,
            forall dir. InstallDirs dir -> dir
    docdir       :: dir,
            forall dir. InstallDirs dir -> dir
    mandir       :: dir,
            forall dir. InstallDirs dir -> dir
    htmldir      :: dir,
            forall dir. InstallDirs dir -> dir
    haddockdir   :: dir,
            forall dir. InstallDirs dir -> dir
    sysconfdir   :: dir
        } deriving (InstallDirs dir -> InstallDirs dir -> Bool
    (InstallDirs dir -> InstallDirs dir -> Bool)
    -> (InstallDirs dir -> InstallDirs dir -> Bool)
    -> Eq (InstallDirs dir)
    forall dir. Eq dir => InstallDirs dir -> InstallDirs dir -> Bool
    forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a
    $c== :: forall dir. Eq dir => InstallDirs dir -> InstallDirs dir -> Bool
    == :: InstallDirs dir -> InstallDirs dir -> Bool
    $c/= :: forall dir. Eq dir => InstallDirs dir -> InstallDirs dir -> Bool
    /= :: InstallDirs dir -> InstallDirs dir -> Bool
    Eq, ReadPrec [InstallDirs dir]
    ReadPrec (InstallDirs dir)
    Int -> ReadS (InstallDirs dir)
    ReadS [InstallDirs dir]
    (Int -> ReadS (InstallDirs dir))
    -> ReadS [InstallDirs dir]
    -> ReadPrec (InstallDirs dir)
    -> ReadPrec [InstallDirs dir]
    -> Read (InstallDirs dir)
    forall dir. Read dir => ReadPrec [InstallDirs dir]
    forall dir. Read dir => ReadPrec (InstallDirs dir)
    forall dir. Read dir => Int -> ReadS (InstallDirs dir)
    forall dir. Read dir => ReadS [InstallDirs dir]
    forall a.
    (Int -> ReadS a)
    -> ReadS [a] -> ReadPrec a -> ReadPrec [a] -> Read a
    $creadsPrec :: forall dir. Read dir => Int -> ReadS (InstallDirs dir)
    readsPrec :: Int -> ReadS (InstallDirs dir)
    $creadList :: forall dir. Read dir => ReadS [InstallDirs dir]
    readList :: ReadS [InstallDirs dir]
    $creadPrec :: forall dir. Read dir => ReadPrec (InstallDirs dir)
    readPrec :: ReadPrec (InstallDirs dir)
    $creadListPrec :: forall dir. Read dir => ReadPrec [InstallDirs dir]
    readListPrec :: ReadPrec [InstallDirs dir]
    Read, Int -> InstallDirs dir -> ShowS
    [InstallDirs dir] -> ShowS
    InstallDirs dir -> FilePath
    (Int -> InstallDirs dir -> ShowS)
    -> (InstallDirs dir -> FilePath)
    -> ([InstallDirs dir] -> ShowS)
    -> Show (InstallDirs dir)
    forall dir. Show dir => Int -> InstallDirs dir -> ShowS
    forall dir. Show dir => [InstallDirs dir] -> ShowS
    forall dir. Show dir => InstallDirs dir -> FilePath
    forall a.
    (Int -> a -> ShowS) -> (a -> FilePath) -> ([a] -> ShowS) -> Show a
    $cshowsPrec :: forall dir. Show dir => Int -> InstallDirs dir -> ShowS
    showsPrec :: Int -> InstallDirs dir -> ShowS
    $cshow :: forall dir. Show dir => InstallDirs dir -> FilePath
    show :: InstallDirs dir -> FilePath
    $cshowList :: forall dir. Show dir => [InstallDirs dir] -> ShowS
    showList :: [InstallDirs dir] -> ShowS
    Show, (forall a b. (a -> b) -> InstallDirs a -> InstallDirs b)
    -> (forall a b. a -> InstallDirs b -> InstallDirs a)
    -> Functor InstallDirs
    forall a b. a -> InstallDirs b -> InstallDirs a
    forall a b. (a -> b) -> InstallDirs a -> InstallDirs b
    forall (f :: * -> *).
    (forall a b. (a -> b) -> f a -> f b)
    -> (forall a b. a -> f b -> f a) -> Functor f
    $cfmap :: forall a b. (a -> b) -> InstallDirs a -> InstallDirs b
    fmap :: forall a b. (a -> b) -> InstallDirs a -> InstallDirs b
    $c<$ :: forall a b. a -> InstallDirs b -> InstallDirs a
    <$ :: forall a b. a -> InstallDirs b -> InstallDirs a
    Functor, (forall x. InstallDirs dir -> Rep (InstallDirs dir) x)
    -> (forall x. Rep (InstallDirs dir) x -> InstallDirs dir)
    -> Generic (InstallDirs dir)
    forall x. Rep (InstallDirs dir) x -> InstallDirs dir
    forall x. InstallDirs dir -> Rep (InstallDirs dir) x
    forall a.
    (forall x. a -> Rep a x) -> (forall x. Rep a x -> a) -> Generic a
    forall dir x. Rep (InstallDirs dir) x -> InstallDirs dir
    forall dir x. InstallDirs dir -> Rep (InstallDirs dir) x
    $cfrom :: forall dir x. InstallDirs dir -> Rep (InstallDirs dir) x
    from :: forall x. InstallDirs dir -> Rep (InstallDirs dir) x
    $cto :: forall dir x. Rep (InstallDirs dir) x -> InstallDirs dir
    to :: forall x. Rep (InstallDirs dir) x -> InstallDirs dir
    Generic, Typeable)

    instance Binary dir => Binary (InstallDirs dir)
    instance Structured dir => Structured (InstallDirs dir)

    instance (Semigroup dir, Monoid dir) => Monoid (InstallDirs dir) where
      mempty :: InstallDirs dir
    mempty = InstallDirs dir
    forall a. (Generic a, GMonoid (Rep a)) => a
    gmempty
      mappend :: InstallDirs dir -> InstallDirs dir -> InstallDirs dir
    mappend = InstallDirs dir -> InstallDirs dir -> InstallDirs dir
    forall a. Semigroup a => a -> a -> a
    (<>)

    instance Semigroup dir => Semigroup (InstallDirs dir) where
      <> :: InstallDirs dir -> InstallDirs dir -> InstallDirs dir
    (<>) = InstallDirs dir -> InstallDirs dir -> InstallDirs dir
    forall a. (Generic a, GSemigroup (Rep a)) => a -> a -> a
    gmappend

    combineInstallDirs :: (a -> b -> c)
                       -> InstallDirs a
                       -> InstallDirs b
                       -> InstallDirs c
    combineInstallDirs :: forall a b c.
    (a -> b -> c) -> InstallDirs a -> InstallDirs b -> InstallDirs c
    combineInstallDirs a -> b -> c
    combine InstallDirs a
    a InstallDirs b
    b = InstallDirs {
        prefix :: c
    prefix       = InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    prefix InstallDirs a
    a     a -> b -> c
    `combine` InstallDirs b -> b
    forall dir. InstallDirs dir -> dir
    prefix InstallDirs b
    b,
        bindir :: c
    bindir       = InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    bindir InstallDirs a
    a     a -> b -> c
    `combine` InstallDirs b -> b
    forall dir. InstallDirs dir -> dir
    bindir InstallDirs b
    b,
        libdir :: c
    libdir       = InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    libdir InstallDirs a
    a     a -> b -> c
    `combine` InstallDirs b -> b
    forall dir. InstallDirs dir -> dir
    libdir InstallDirs b
    b,
        libsubdir :: c
    libsubdir    = InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    libsubdir InstallDirs a
    a  a -> b -> c
    `combine` InstallDirs b -> b
    forall dir. InstallDirs dir -> dir
    libsubdir InstallDirs b
    b,
        dynlibdir :: c
    dynlibdir    = InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    dynlibdir InstallDirs a
    a  a -> b -> c
    `combine` InstallDirs b -> b
    forall dir. InstallDirs dir -> dir
    dynlibdir InstallDirs b
    b,
        flibdir :: c
    flibdir      = InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    flibdir InstallDirs a
    a    a -> b -> c
    `combine` InstallDirs b -> b
    forall dir. InstallDirs dir -> dir
    flibdir InstallDirs b
    b,
        libexecdir :: c
    libexecdir   = InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    libexecdir InstallDirs a
    a a -> b -> c
    `combine` InstallDirs b -> b
    forall dir. InstallDirs dir -> dir
    libexecdir InstallDirs b
    b,
        libexecsubdir :: c
    libexecsubdir= InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    libexecsubdir InstallDirs a
    a a -> b -> c
    `combine` InstallDirs b -> b
    forall dir. InstallDirs dir -> dir
    libexecsubdir InstallDirs b
    b,
        includedir :: c
    includedir   = InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    includedir InstallDirs a
    a a -> b -> c
    `combine` InstallDirs b -> b
    forall dir. InstallDirs dir -> dir
    includedir InstallDirs b
    b,
        datadir :: c
    datadir      = InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    datadir InstallDirs a
    a    a -> b -> c
    `combine` InstallDirs b -> b
    forall dir. InstallDirs dir -> dir
    datadir InstallDirs b
    b,
        datasubdir :: c
    datasubdir   = InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    datasubdir InstallDirs a
    a a -> b -> c
    `combine` InstallDirs b -> b
    forall dir. InstallDirs dir -> dir
    datasubdir InstallDirs b
    b,
        docdir :: c
    docdir       = InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    docdir InstallDirs a
    a     a -> b -> c
    `combine` InstallDirs b -> b
    forall dir. InstallDirs dir -> dir
    docdir InstallDirs b
    b,
        mandir :: c
    mandir       = InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    mandir InstallDirs a
    a     a -> b -> c
    `combine` InstallDirs b -> b
    forall dir. InstallDirs dir -> dir
    mandir InstallDirs b
    b,
        htmldir :: c
    htmldir      = InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    htmldir InstallDirs a
    a    a -> b -> c
    `combine` InstallDirs b -> b
    forall dir. InstallDirs dir -> dir
    htmldir InstallDirs b
    b,
        haddockdir :: c
    haddockdir   = InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    haddockdir InstallDirs a
    a a -> b -> c
    `combine` InstallDirs b -> b
    forall dir. InstallDirs dir -> dir
    haddockdir InstallDirs b
    b,
        sysconfdir :: c
    sysconfdir   = InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    sysconfdir InstallDirs a
    a a -> b -> c
    `combine` InstallDirs b -> b
    forall dir. InstallDirs dir -> dir
    sysconfdir InstallDirs b
    b
      }

    appendSubdirs :: (a -> a -> a) -> InstallDirs a -> InstallDirs a
    appendSubdirs :: forall a. (a -> a -> a) -> InstallDirs a -> InstallDirs a
    appendSubdirs a -> a -> a
    append InstallDirs a
    dirs = InstallDirs a
    dirs {
        libdir :: a
    libdir     = InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    libdir InstallDirs a
    dirs a -> a -> a
    `append` InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    libsubdir InstallDirs a
    dirs,
        libexecdir :: a
    libexecdir = InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    libexecdir InstallDirs a
    dirs a -> a -> a
    `append` InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    libexecsubdir InstallDirs a
    dirs,
        datadir :: a
    datadir    = InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    datadir InstallDirs a
    dirs a -> a -> a
    `append` InstallDirs a -> a
    forall dir. InstallDirs dir -> dir
    datasubdir InstallDirs a
    dirs,
        libsubdir :: a
    libsubdir  = FilePath -> a
    forall a. HasCallStack => FilePath -> a
    error FilePath
    "internal error InstallDirs.libsubdir",
        libexecsubdir :: a
    libexecsubdir = FilePath -> a
    forall a. HasCallStack => FilePath -> a
    error FilePath
    "internal error InstallDirs.libexecsubdir",
        datasubdir :: a
    datasubdir = FilePath -> a
    forall a. HasCallStack => FilePath -> a
    error FilePath
    "internal error InstallDirs.datasubdir"
      }

    -- | The installation directories in terms of 'PathTemplate's that contain
    -- variables.
    --
    -- The defaults for most of the directories are relative to each other, in
    -- particular they are all relative to a single prefix. This makes it
    -- convenient for the user to override the default installation directory
    -- by only having to specify --prefix=... rather than overriding each
    -- individually. This is done by allowing $-style variables in the dirs.
    -- These are expanded by textual substitution (see 'substPathTemplate').
    --
    -- A few of these installation directories are split into two components, the
    -- dir and subdir. The full installation path is formed by combining the two
    -- together with @\/@. The reason for this is compatibility with other Unix
    -- build systems which also support @--libdir@ and @--datadir@. We would like
    -- users to be able to configure @--libdir=\/usr\/lib64@ for example but
    -- because by default we want to support installing multiple versions of
    -- packages and building the same package for multiple compilers we append the
    -- libsubdir to get: @\/usr\/lib64\/$libname\/$compiler@.
    --
    -- An additional complication is the need to support relocatable packages on
    -- systems which support such things, like Windows.
    --
    type InstallDirTemplates = InstallDirs PathTemplate

    -- ---------------------------------------------------------------------------
    -- Default installation directories

    defaultInstallDirs :: CompilerFlavor -> Bool -> Bool -> IO InstallDirTemplates
    defaultInstallDirs :: CompilerFlavor -> Bool -> Bool -> IO InstallDirTemplates
    defaultInstallDirs = Bool -> CompilerFlavor -> Bool -> Bool -> IO InstallDirTemplates
    defaultInstallDirs' Bool
    False

    defaultInstallDirs' :: Bool {- use external internal deps -}
                        -> CompilerFlavor -> Bool -> Bool -> IO InstallDirTemplates
    defaultInstallDirs' :: Bool -> CompilerFlavor -> Bool -> Bool -> IO InstallDirTemplates
    defaultInstallDirs' Bool
    True CompilerFlavor
    comp Bool
    userInstall Bool
    hasLibs = do
      InstallDirTemplates
    dflt <- Bool -> CompilerFlavor -> Bool -> Bool -> IO InstallDirTemplates
    defaultInstallDirs' Bool
    False CompilerFlavor
    comp Bool
    userInstall Bool
    hasLibs
      -- Be a bit more hermetic about per-component installs
      InstallDirTemplates -> IO InstallDirTemplates
    forall a. a -> IO a
    forall (m :: * -> *) a. Monad m => a -> m a
    return InstallDirTemplates
    dflt { datasubdir :: PathTemplate
    datasubdir = FilePath -> PathTemplate
    toPathTemplate (FilePath -> PathTemplate) -> FilePath -> PathTemplate
    forall a b. (a -> b) -> a -> b
    $ FilePath
    "$abi" FilePath -> ShowS
    </> FilePath
    "$libname",
                    docdir :: PathTemplate
    docdir     = FilePath -> PathTemplate
    toPathTemplate (FilePath -> PathTemplate) -> FilePath -> PathTemplate
    forall a b. (a -> b) -> a -> b
    $ FilePath
    "$datadir" FilePath -> ShowS
    </> FilePath
    "doc" FilePath -> ShowS
    </> FilePath
    "$abi" FilePath -> ShowS
    </> FilePath
    "$libname"
                  }
    defaultInstallDirs' Bool
    False CompilerFlavor
    comp Bool
    userInstall Bool
    _hasLibs = do
      FilePath
    installPrefix <-
          if Bool
    userInstall
          then do
            Maybe FilePath
    mDir <- FilePath -> IO (Maybe FilePath)
    lookupEnv FilePath
    "CABAL_DIR"
            case Maybe FilePath
    mDir of
              Maybe FilePath
    Nothing -> FilePath -> IO FilePath
    getAppUserDataDirectory FilePath
    "cabal"
              Just FilePath
    dir -> FilePath -> IO FilePath
    forall a. a -> IO a
    forall (m :: * -> *) a. Monad m => a -> m a
    return FilePath
    dir
          else case OS
    buildOS of
               OS
    Windows -> do FilePath
    windowsProgramFilesDir <- IO FilePath
    getWindowsProgramFilesDir
                             FilePath -> IO FilePath
    forall a. a -> IO a
    forall (m :: * -> *) a. Monad m => a -> m a
    return (FilePath
    windowsProgramFilesDir FilePath -> ShowS
    </> FilePath
    "Haskell")
               OS
    _       -> FilePath -> IO FilePath
    forall a. a -> IO a
    forall (m :: * -> *) a. Monad m => a -> m a
    return FilePath
    "/usr/local"
      FilePath
    installLibDir <-
          case OS
    buildOS of
          OS
    Windows -> FilePath -> IO FilePath
    forall a. a -> IO a
    forall (m :: * -> *) a. Monad m => a -> m a
    return FilePath
    "$prefix"
          OS
    _       -> FilePath -> IO FilePath
    forall a. a -> IO a
    forall (m :: * -> *) a. Monad m => a -> m a
    return (FilePath
    "$prefix" FilePath -> ShowS
    </> FilePath
    "lib")
      InstallDirTemplates -> IO InstallDirTemplates
    forall a. a -> IO a
    forall (m :: * -> *) a. Monad m => a -> m a
    return (InstallDirTemplates -> IO InstallDirTemplates)
    -> InstallDirTemplates -> IO InstallDirTemplates
    forall a b. (a -> b) -> a -> b
    $ (FilePath -> PathTemplate)
    -> InstallDirs FilePath -> InstallDirTemplates
    forall a b. (a -> b) -> InstallDirs a -> InstallDirs b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    fmap FilePath -> PathTemplate
    toPathTemplate (InstallDirs FilePath -> InstallDirTemplates)
    -> InstallDirs FilePath -> InstallDirTemplates
    forall a b. (a -> b) -> a -> b
    $ InstallDirs {
          prefix :: FilePath
    prefix       = FilePath
    installPrefix,
          bindir :: FilePath
    bindir       = FilePath
    "$prefix" FilePath -> ShowS
    </> FilePath
    "bin",
          libdir :: FilePath
    libdir       = FilePath
    installLibDir,
          libsubdir :: FilePath
    libsubdir    = case CompilerFlavor
    comp of
               CompilerFlavor
    UHC    -> FilePath
    "$pkgid"
               CompilerFlavor
    _other -> FilePath
    "$abi" FilePath -> ShowS
    </> FilePath
    "$libname",
          dynlibdir :: FilePath
    dynlibdir    = FilePath
    "$libdir" FilePath -> ShowS
    </> case CompilerFlavor
    comp of
               CompilerFlavor
    UHC    -> FilePath
    "$pkgid"
               CompilerFlavor
    _other -> FilePath
    "$abi",
          libexecsubdir :: FilePath
    libexecsubdir= FilePath
    "$abi" FilePath -> ShowS
    </> FilePath
    "$pkgid",
          flibdir :: FilePath
    flibdir      = FilePath
    "$libdir",
          libexecdir :: FilePath
    libexecdir   = case OS
    buildOS of
            OS
    Windows   -> FilePath
    "$prefix" FilePath -> ShowS
    </> FilePath
    "$libname"
            OS
    _other    -> FilePath
    "$prefix" FilePath -> ShowS
    </> FilePath
    "libexec",
          includedir :: FilePath
    includedir   = FilePath
    "$libdir" FilePath -> ShowS
    </> FilePath
    "$libsubdir" FilePath -> ShowS
    </> FilePath
    "include",
          datadir :: FilePath
    datadir      = case OS
    buildOS of
            OS
    Windows   -> FilePath
    "$prefix"
            OS
    _other    -> FilePath
    "$prefix" FilePath -> ShowS
    </> FilePath
    "share",
          datasubdir :: FilePath
    datasubdir   = FilePath
    "$abi" FilePath -> ShowS
    </> FilePath
    "$pkgid",
          docdir :: FilePath
    docdir       = FilePath
    "$datadir" FilePath -> ShowS
    </> FilePath
    "doc" FilePath -> ShowS
    </> FilePath
    "$abi" FilePath -> ShowS
    </> FilePath
    "$pkgid",
          mandir :: FilePath
    mandir       = FilePath
    "$datadir" FilePath -> ShowS
    </> FilePath
    "man",
          htmldir :: FilePath
    htmldir      = FilePath
    "$docdir"  FilePath -> ShowS
    </> FilePath
    "html",
          haddockdir :: FilePath
    haddockdir   = FilePath
    "$htmldir",
          sysconfdir :: FilePath
    sysconfdir   = FilePath
    "$prefix" FilePath -> ShowS
    </> FilePath
    "etc"
      }

    -- ---------------------------------------------------------------------------
    -- Converting directories, absolute or prefix-relative

    -- | Substitute the install dir templates into each other.
    --
    -- To prevent cyclic substitutions, only some variables are allowed in
    -- particular dir templates. If out of scope vars are present, they are not
    -- substituted for. Checking for any remaining unsubstituted vars can be done
    -- as a subsequent operation.
    --
    -- The reason it is done this way is so that in 'prefixRelativeInstallDirs' we
    -- can replace 'prefix' with the 'PrefixVar' and get resulting
    -- 'PathTemplate's that still have the 'PrefixVar' in them. Doing this makes it
    -- each to check which paths are relative to the $prefix.
    --
    substituteInstallDirTemplates :: PathTemplateEnv
                                  -> InstallDirTemplates -> InstallDirTemplates
    substituteInstallDirTemplates :: PathTemplateEnv -> InstallDirTemplates -> InstallDirTemplates
    substituteInstallDirTemplates PathTemplateEnv
    env InstallDirTemplates
    dirs = InstallDirTemplates
    dirs'
      where
        dirs' :: InstallDirTemplates
    dirs' = InstallDirs {
          -- So this specifies exactly which vars are allowed in each template
          prefix :: PathTemplate
    prefix     = (InstallDirTemplates -> PathTemplate)
    -> PathTemplateEnv -> PathTemplate
    subst InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    prefix     [],
          bindir :: PathTemplate
    bindir     = (InstallDirTemplates -> PathTemplate)
    -> PathTemplateEnv -> PathTemplate
    subst InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    bindir     [(PathTemplateVariable, PathTemplate)
    prefixVar],
          libdir :: PathTemplate
    libdir     = (InstallDirTemplates -> PathTemplate)
    -> PathTemplateEnv -> PathTemplate
    subst InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    libdir     [(PathTemplateVariable, PathTemplate)
    prefixVar, (PathTemplateVariable, PathTemplate)
    bindirVar],
          libsubdir :: PathTemplate
    libsubdir  = (InstallDirTemplates -> PathTemplate)
    -> PathTemplateEnv -> PathTemplate
    subst InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    libsubdir  [],
          dynlibdir :: PathTemplate
    dynlibdir  = (InstallDirTemplates -> PathTemplate)
    -> PathTemplateEnv -> PathTemplate
    subst InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    dynlibdir  [(PathTemplateVariable, PathTemplate)
    prefixVar, (PathTemplateVariable, PathTemplate)
    bindirVar, (PathTemplateVariable, PathTemplate)
    libdirVar],
          flibdir :: PathTemplate
    flibdir    = (InstallDirTemplates -> PathTemplate)
    -> PathTemplateEnv -> PathTemplate
    subst InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    flibdir    [(PathTemplateVariable, PathTemplate)
    prefixVar, (PathTemplateVariable, PathTemplate)
    bindirVar, (PathTemplateVariable, PathTemplate)
    libdirVar],
          libexecdir :: PathTemplate
    libexecdir = (InstallDirTemplates -> PathTemplate)
    -> PathTemplateEnv -> PathTemplate
    subst InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    libexecdir PathTemplateEnv
    prefixBinLibVars,
          libexecsubdir :: PathTemplate
    libexecsubdir = (InstallDirTemplates -> PathTemplate)
    -> PathTemplateEnv -> PathTemplate
    subst InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    libexecsubdir [],
          includedir :: PathTemplate
    includedir = (InstallDirTemplates -> PathTemplate)
    -> PathTemplateEnv -> PathTemplate
    subst InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    includedir PathTemplateEnv
    prefixBinLibVars,
          datadir :: PathTemplate
    datadir    = (InstallDirTemplates -> PathTemplate)
    -> PathTemplateEnv -> PathTemplate
    subst InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    datadir    PathTemplateEnv
    prefixBinLibVars,
          datasubdir :: PathTemplate
    datasubdir = (InstallDirTemplates -> PathTemplate)
    -> PathTemplateEnv -> PathTemplate
    subst InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    datasubdir [],
          docdir :: PathTemplate
    docdir     = (InstallDirTemplates -> PathTemplate)
    -> PathTemplateEnv -> PathTemplate
    subst InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    docdir     PathTemplateEnv
    prefixBinLibDataVars,
          mandir :: PathTemplate
    mandir     = (InstallDirTemplates -> PathTemplate)
    -> PathTemplateEnv -> PathTemplate
    subst InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    mandir     (PathTemplateEnv
    prefixBinLibDataVars PathTemplateEnv -> PathTemplateEnv -> PathTemplateEnv
    forall a. [a] -> [a] -> [a]
    ++ [(PathTemplateVariable, PathTemplate)
    docdirVar]),
          htmldir :: PathTemplate
    htmldir    = (InstallDirTemplates -> PathTemplate)
    -> PathTemplateEnv -> PathTemplate
    subst InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    htmldir    (PathTemplateEnv
    prefixBinLibDataVars PathTemplateEnv -> PathTemplateEnv -> PathTemplateEnv
    forall a. [a] -> [a] -> [a]
    ++ [(PathTemplateVariable, PathTemplate)
    docdirVar]),
          haddockdir :: PathTemplate
    haddockdir = (InstallDirTemplates -> PathTemplate)
    -> PathTemplateEnv -> PathTemplate
    subst InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    haddockdir (PathTemplateEnv
    prefixBinLibDataVars PathTemplateEnv -> PathTemplateEnv -> PathTemplateEnv
    forall a. [a] -> [a] -> [a]
    ++
                                          [(PathTemplateVariable, PathTemplate)
    docdirVar, (PathTemplateVariable, PathTemplate)
    htmldirVar]),
          sysconfdir :: PathTemplate
    sysconfdir = (InstallDirTemplates -> PathTemplate)
    -> PathTemplateEnv -> PathTemplate
    subst InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    sysconfdir PathTemplateEnv
    prefixBinLibVars
        }
        subst :: (InstallDirTemplates -> PathTemplate)
    -> PathTemplateEnv -> PathTemplate
    subst InstallDirTemplates -> PathTemplate
    dir PathTemplateEnv
    env' = PathTemplateEnv -> PathTemplate -> PathTemplate
    substPathTemplate (PathTemplateEnv
    env'PathTemplateEnv -> PathTemplateEnv -> PathTemplateEnv
    forall a. [a] -> [a] -> [a]
    ++PathTemplateEnv
    env) (InstallDirTemplates -> PathTemplate
    dir InstallDirTemplates
    dirs)

        prefixVar :: (PathTemplateVariable, PathTemplate)
    prefixVar        = (PathTemplateVariable
    PrefixVar,     InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    prefix     InstallDirTemplates
    dirs')
        bindirVar :: (PathTemplateVariable, PathTemplate)
    bindirVar        = (PathTemplateVariable
    BindirVar,     InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    bindir     InstallDirTemplates
    dirs')
        libdirVar :: (PathTemplateVariable, PathTemplate)
    libdirVar        = (PathTemplateVariable
    LibdirVar,     InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    libdir     InstallDirTemplates
    dirs')
        libsubdirVar :: (PathTemplateVariable, PathTemplate)
    libsubdirVar     = (PathTemplateVariable
    LibsubdirVar,  InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    libsubdir  InstallDirTemplates
    dirs')
        datadirVar :: (PathTemplateVariable, PathTemplate)
    datadirVar       = (PathTemplateVariable
    DatadirVar,    InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    datadir    InstallDirTemplates
    dirs')
        datasubdirVar :: (PathTemplateVariable, PathTemplate)
    datasubdirVar    = (PathTemplateVariable
    DatasubdirVar, InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    datasubdir InstallDirTemplates
    dirs')
        docdirVar :: (PathTemplateVariable, PathTemplate)
    docdirVar        = (PathTemplateVariable
    DocdirVar,     InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    docdir     InstallDirTemplates
    dirs')
        htmldirVar :: (PathTemplateVariable, PathTemplate)
    htmldirVar       = (PathTemplateVariable
    HtmldirVar,    InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    htmldir    InstallDirTemplates
    dirs')
        prefixBinLibVars :: PathTemplateEnv
    prefixBinLibVars = [(PathTemplateVariable, PathTemplate)
    prefixVar, (PathTemplateVariable, PathTemplate)
    bindirVar, (PathTemplateVariable, PathTemplate)
    libdirVar, (PathTemplateVariable, PathTemplate)
    libsubdirVar]
        prefixBinLibDataVars :: PathTemplateEnv
    prefixBinLibDataVars = PathTemplateEnv
    prefixBinLibVars PathTemplateEnv -> PathTemplateEnv -> PathTemplateEnv
    forall a. [a] -> [a] -> [a]
    ++ [(PathTemplateVariable, PathTemplate)
    datadirVar, (PathTemplateVariable, PathTemplate)
    datasubdirVar]

    -- | Convert from abstract install directories to actual absolute ones by
    -- substituting for all the variables in the abstract paths, to get real
    -- absolute path.
    absoluteInstallDirs :: PackageIdentifier
                        -> UnitId
                        -> CompilerInfo
                        -> CopyDest
                        -> Platform
                        -> InstallDirs PathTemplate
                        -> InstallDirs FilePath
    absoluteInstallDirs :: PackageIdentifier
    -> UnitId
    -> CompilerInfo
    -> CopyDest
    -> Platform
    -> InstallDirTemplates
    -> InstallDirs FilePath
    absoluteInstallDirs PackageIdentifier
    pkgId UnitId
    libname CompilerInfo
    compilerId CopyDest
    copydest Platform
    platform InstallDirTemplates
    dirs =
        (case CopyDest
    copydest of
           CopyTo FilePath
    destdir -> ShowS -> InstallDirs FilePath -> InstallDirs FilePath
    forall a b. (a -> b) -> InstallDirs a -> InstallDirs b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    fmap ((FilePath
    destdir FilePath -> ShowS
    </>) ShowS -> ShowS -> ShowS
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . ShowS
    dropDrive)
           CopyToDb FilePath
    dbdir -> ShowS -> InstallDirs FilePath -> InstallDirs FilePath
    forall a b. (a -> b) -> InstallDirs a -> InstallDirs b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    fmap (FilePath -> FilePath -> ShowS
    forall {a}. Eq a => [a] -> [a] -> [a] -> [a]
    substPrefix FilePath
    "${pkgroot}" (ShowS
    takeDirectory FilePath
    dbdir))
           CopyDest
    _              -> InstallDirs FilePath -> InstallDirs FilePath
    forall a. a -> a
    id)
      (InstallDirs FilePath -> InstallDirs FilePath)
    -> (InstallDirTemplates -> InstallDirs FilePath)
    -> InstallDirTemplates
    -> InstallDirs FilePath
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . (FilePath -> ShowS) -> InstallDirs FilePath -> InstallDirs FilePath
    forall a. (a -> a -> a) -> InstallDirs a -> InstallDirs a
    appendSubdirs FilePath -> ShowS
    (</>)
      (InstallDirs FilePath -> InstallDirs FilePath)
    -> (InstallDirTemplates -> InstallDirs FilePath)
    -> InstallDirTemplates
    -> InstallDirs FilePath
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . (PathTemplate -> FilePath)
    -> InstallDirTemplates -> InstallDirs FilePath
    forall a b. (a -> b) -> InstallDirs a -> InstallDirs b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    fmap PathTemplate -> FilePath
    fromPathTemplate
      (InstallDirTemplates -> InstallDirs FilePath)
    -> InstallDirTemplates -> InstallDirs FilePath
    forall a b. (a -> b) -> a -> b
    $ PathTemplateEnv -> InstallDirTemplates -> InstallDirTemplates
    substituteInstallDirTemplates PathTemplateEnv
    env InstallDirTemplates
    dirs
      where
        env :: PathTemplateEnv
    env = PackageIdentifier
    -> UnitId -> CompilerInfo -> Platform -> PathTemplateEnv
    initialPathTemplateEnv PackageIdentifier
    pkgId UnitId
    libname CompilerInfo
    compilerId Platform
    platform
        substPrefix :: [a] -> [a] -> [a] -> [a]
    substPrefix [a]
    pre [a]
    root [a]
    path
          | [a]
    pre [a] -> [a] -> Bool
    forall a. Eq a => [a] -> [a] -> Bool
    `isPrefixOf` [a]
    path = [a]
    root [a] -> [a] -> [a]
    forall a. [a] -> [a] -> [a]
    ++ Int -> [a] -> [a]
    forall a. Int -> [a] -> [a]
    drop ([a] -> Int
    forall a. [a] -> Int
    forall (t :: * -> *) a. Foldable t => t a -> Int
    length [a]
    pre) [a]
    path
          | Bool
    otherwise             = [a]
    path

    -- |The location prefix for the /copy/ command.
    data CopyDest
      = NoCopyDest
      | CopyTo FilePath
      | CopyToDb FilePath
      -- ^ when using the ${pkgroot} as prefix. The CopyToDb will
      --   adjust the paths to be relative to the provided package
      --   database when copying / installing.
      deriving (CopyDest -> CopyDest -> Bool
    (CopyDest -> CopyDest -> Bool)
    -> (CopyDest -> CopyDest -> Bool) -> Eq CopyDest
    forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a
    $c== :: CopyDest -> CopyDest -> Bool
    == :: CopyDest -> CopyDest -> Bool
    $c/= :: CopyDest -> CopyDest -> Bool
    /= :: CopyDest -> CopyDest -> Bool
    Eq, Int -> CopyDest -> ShowS
    [CopyDest] -> ShowS
    CopyDest -> FilePath
    (Int -> CopyDest -> ShowS)
    -> (CopyDest -> FilePath) -> ([CopyDest] -> ShowS) -> Show CopyDest
    forall a.
    (Int -> a -> ShowS) -> (a -> FilePath) -> ([a] -> ShowS) -> Show a
    $cshowsPrec :: Int -> CopyDest -> ShowS
    showsPrec :: Int -> CopyDest -> ShowS
    $cshow :: CopyDest -> FilePath
    show :: CopyDest -> FilePath
    $cshowList :: [CopyDest] -> ShowS
    showList :: [CopyDest] -> ShowS
    Show, (forall x. CopyDest -> Rep CopyDest x)
    -> (forall x. Rep CopyDest x -> CopyDest) -> Generic CopyDest
    forall x. Rep CopyDest x -> CopyDest
    forall x. CopyDest -> Rep CopyDest x
    forall a.
    (forall x. a -> Rep a x) -> (forall x. Rep a x -> a) -> Generic a
    $cfrom :: forall x. CopyDest -> Rep CopyDest x
    from :: forall x. CopyDest -> Rep CopyDest x
    $cto :: forall x. Rep CopyDest x -> CopyDest
    to :: forall x. Rep CopyDest x -> CopyDest
    Generic)

    instance Binary CopyDest

    -- | Check which of the paths are relative to the installation $prefix.
    --
    -- If any of the paths are not relative, ie they are absolute paths, then it
    -- prevents us from making a relocatable package (also known as a \"prefix
    -- independent\" package).
    --
    prefixRelativeInstallDirs :: PackageIdentifier
                              -> UnitId
                              -> CompilerInfo
                              -> Platform
                              -> InstallDirTemplates
                              -> InstallDirs (Maybe FilePath)
    prefixRelativeInstallDirs :: PackageIdentifier
    -> UnitId
    -> CompilerInfo
    -> Platform
    -> InstallDirTemplates
    -> InstallDirs (Maybe FilePath)
    prefixRelativeInstallDirs PackageIdentifier
    pkgId UnitId
    libname CompilerInfo
    compilerId Platform
    platform InstallDirTemplates
    dirs =
        (PathTemplate -> Maybe FilePath)
    -> InstallDirTemplates -> InstallDirs (Maybe FilePath)
    forall a b. (a -> b) -> InstallDirs a -> InstallDirs b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    fmap PathTemplate -> Maybe FilePath
    relative
      (InstallDirTemplates -> InstallDirs (Maybe FilePath))
    -> (InstallDirTemplates -> InstallDirTemplates)
    -> InstallDirTemplates
    -> InstallDirs (Maybe FilePath)
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . (PathTemplate -> PathTemplate -> PathTemplate)
    -> InstallDirTemplates -> InstallDirTemplates
    forall a. (a -> a -> a) -> InstallDirs a -> InstallDirs a
    appendSubdirs PathTemplate -> PathTemplate -> PathTemplate
    combinePathTemplate
      (InstallDirTemplates -> InstallDirs (Maybe FilePath))
    -> InstallDirTemplates -> InstallDirs (Maybe FilePath)
    forall a b. (a -> b) -> a -> b
    $ -- substitute the path template into each other, except that we map
        -- \$prefix back to $prefix. We're trying to end up with templates that
        -- mention no vars except $prefix.
        PathTemplateEnv -> InstallDirTemplates -> InstallDirTemplates
    substituteInstallDirTemplates PathTemplateEnv
    env InstallDirTemplates
    dirs {
          prefix :: PathTemplate
    prefix = [PathComponent] -> PathTemplate
    PathTemplate [PathTemplateVariable -> PathComponent
    Variable PathTemplateVariable
    PrefixVar]
        }
      where
        env :: PathTemplateEnv
    env = PackageIdentifier
    -> UnitId -> CompilerInfo -> Platform -> PathTemplateEnv
    initialPathTemplateEnv PackageIdentifier
    pkgId UnitId
    libname CompilerInfo
    compilerId Platform
    platform

        -- If it starts with $prefix then it's relative and produce the relative
        -- path by stripping off $prefix/ or $prefix
        relative :: PathTemplate -> Maybe FilePath
    relative PathTemplate
    dir = case PathTemplate
    dir of
          PathTemplate [PathComponent]
    cs -> ([PathComponent] -> FilePath)
    -> Maybe [PathComponent] -> Maybe FilePath
    forall a b. (a -> b) -> Maybe a -> Maybe b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    fmap (PathTemplate -> FilePath
    fromPathTemplate (PathTemplate -> FilePath)
    -> ([PathComponent] -> PathTemplate) -> [PathComponent] -> FilePath
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . [PathComponent] -> PathTemplate
    PathTemplate) ([PathComponent] -> Maybe [PathComponent]
    relative' [PathComponent]
    cs)
        relative' :: [PathComponent] -> Maybe [PathComponent]
    relative' (Variable PathTemplateVariable
    PrefixVar : Ordinary (Char
    s:FilePath
    rest) : [PathComponent]
    rest')
                          | Char -> Bool
    isPathSeparator Char
    s = [PathComponent] -> Maybe [PathComponent]
    forall a. a -> Maybe a
    Just (FilePath -> PathComponent
    Ordinary FilePath
    rest PathComponent -> [PathComponent] -> [PathComponent]
    forall a. a -> [a] -> [a]
    : [PathComponent]
    rest')
        relative' (Variable PathTemplateVariable
    PrefixVar : [PathComponent]
    rest) = [PathComponent] -> Maybe [PathComponent]
    forall a. a -> Maybe a
    Just [PathComponent]
    rest
        relative' [PathComponent]
    _                           = Maybe [PathComponent]
    forall a. Maybe a
    Nothing

    -- ---------------------------------------------------------------------------
    -- Path templates

    -- | An abstract path, possibly containing variables that need to be
    -- substituted for to get a real 'FilePath'.
    --
    newtype PathTemplate = PathTemplate [PathComponent]
      deriving (PathTemplate -> PathTemplate -> Bool
    (PathTemplate -> PathTemplate -> Bool)
    -> (PathTemplate -> PathTemplate -> Bool) -> Eq PathTemplate
    forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a
    $c== :: PathTemplate -> PathTemplate -> Bool
    == :: PathTemplate -> PathTemplate -> Bool
    $c/= :: PathTemplate -> PathTemplate -> Bool
    /= :: PathTemplate -> PathTemplate -> Bool
    Eq, Eq PathTemplate
    Eq PathTemplate
    -> (PathTemplate -> PathTemplate -> Ordering)
    -> (PathTemplate -> PathTemplate -> Bool)
    -> (PathTemplate -> PathTemplate -> Bool)
    -> (PathTemplate -> PathTemplate -> Bool)
    -> (PathTemplate -> PathTemplate -> Bool)
    -> (PathTemplate -> PathTemplate -> PathTemplate)
    -> (PathTemplate -> PathTemplate -> PathTemplate)
    -> Ord PathTemplate
    PathTemplate -> PathTemplate -> Bool
    PathTemplate -> PathTemplate -> Ordering
    PathTemplate -> PathTemplate -> PathTemplate
    forall a.
    Eq a
    -> (a -> a -> Ordering)
    -> (a -> a -> Bool)
    -> (a -> a -> Bool)
    -> (a -> a -> Bool)
    -> (a -> a -> Bool)
    -> (a -> a -> a)
    -> (a -> a -> a)
    -> Ord a
    $ccompare :: PathTemplate -> PathTemplate -> Ordering
    compare :: PathTemplate -> PathTemplate -> Ordering
    $c< :: PathTemplate -> PathTemplate -> Bool
    < :: PathTemplate -> PathTemplate -> Bool
    $c<= :: PathTemplate -> PathTemplate -> Bool
    <= :: PathTemplate -> PathTemplate -> Bool
    $c> :: PathTemplate -> PathTemplate -> Bool
    > :: PathTemplate -> PathTemplate -> Bool
    $c>= :: PathTemplate -> PathTemplate -> Bool
    >= :: PathTemplate -> PathTemplate -> Bool
    $cmax :: PathTemplate -> PathTemplate -> PathTemplate
    max :: PathTemplate -> PathTemplate -> PathTemplate
    $cmin :: PathTemplate -> PathTemplate -> PathTemplate
    min :: PathTemplate -> PathTemplate -> PathTemplate
    Ord, (forall x. PathTemplate -> Rep PathTemplate x)
    -> (forall x. Rep PathTemplate x -> PathTemplate)
    -> Generic PathTemplate
    forall x. Rep PathTemplate x -> PathTemplate
    forall x. PathTemplate -> Rep PathTemplate x
    forall a.
    (forall x. a -> Rep a x) -> (forall x. Rep a x -> a) -> Generic a
    $cfrom :: forall x. PathTemplate -> Rep PathTemplate x
    from :: forall x. PathTemplate -> Rep PathTemplate x
    $cto :: forall x. Rep PathTemplate x -> PathTemplate
    to :: forall x. Rep PathTemplate x -> PathTemplate
    Generic, Typeable)

    instance Binary PathTemplate
    instance Structured PathTemplate

    type PathTemplateEnv = [(PathTemplateVariable, PathTemplate)]

    -- | Convert a 'FilePath' to a 'PathTemplate' including any template vars.
    --
    toPathTemplate :: FilePath -> PathTemplate
    toPathTemplate :: FilePath -> PathTemplate
    toPathTemplate FilePath
    fp = [PathComponent] -> PathTemplate
    PathTemplate
        ([PathComponent] -> PathTemplate)
    -> (FilePath -> [PathComponent]) -> FilePath -> PathTemplate
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . [PathComponent] -> Maybe [PathComponent] -> [PathComponent]
    forall a. a -> Maybe a -> a
    fromMaybe (FilePath -> [PathComponent]
    forall a. HasCallStack => FilePath -> a
    error (FilePath -> [PathComponent]) -> FilePath -> [PathComponent]
    forall a b. (a -> b) -> a -> b
    $ FilePath
    "panic! toPathTemplate " FilePath -> ShowS
    forall a. [a] -> [a] -> [a]
    ++ ShowS
    forall a. Show a => a -> FilePath
    show FilePath
    fp)
        (Maybe [PathComponent] -> [PathComponent])
    -> (FilePath -> Maybe [PathComponent])
    -> FilePath
    -> [PathComponent]
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . FilePath -> Maybe [PathComponent]
    forall a. Read a => FilePath -> Maybe a
    readMaybe -- TODO: eradicateNoParse
        (FilePath -> PathTemplate) -> FilePath -> PathTemplate
    forall a b. (a -> b) -> a -> b
    $ FilePath
    fp

    -- | Convert back to a path, any remaining vars are included
    --
    fromPathTemplate :: PathTemplate -> FilePath
    fromPathTemplate :: PathTemplate -> FilePath
    fromPathTemplate (PathTemplate [PathComponent]
    template) = [PathComponent] -> FilePath
    forall a. Show a => a -> FilePath
    show [PathComponent]
    template

    combinePathTemplate :: PathTemplate -> PathTemplate -> PathTemplate
    combinePathTemplate :: PathTemplate -> PathTemplate -> PathTemplate
    combinePathTemplate (PathTemplate [PathComponent]
    t1) (PathTemplate [PathComponent]
    t2) =
      [PathComponent] -> PathTemplate
    PathTemplate ([PathComponent]
    t1 [PathComponent] -> [PathComponent] -> [PathComponent]
    forall a. [a] -> [a] -> [a]
    ++ [FilePath -> PathComponent
    Ordinary [Char
    pathSeparator]] [PathComponent] -> [PathComponent] -> [PathComponent]
    forall a. [a] -> [a] -> [a]
    ++ [PathComponent]
    t2)

    substPathTemplate :: PathTemplateEnv -> PathTemplate -> PathTemplate
    substPathTemplate :: PathTemplateEnv -> PathTemplate -> PathTemplate
    substPathTemplate PathTemplateEnv
    environment (PathTemplate [PathComponent]
    template) =
        [PathComponent] -> PathTemplate
    PathTemplate ((PathComponent -> [PathComponent])
    -> [PathComponent] -> [PathComponent]
    forall (t :: * -> *) a b. Foldable t => (a -> [b]) -> t a -> [b]
    concatMap PathComponent -> [PathComponent]
    subst [PathComponent]
    template)

        where subst :: PathComponent -> [PathComponent]
    subst component :: PathComponent
    component@(Ordinary FilePath
    _) = [PathComponent
    component]
              subst component :: PathComponent
    component@(Variable PathTemplateVariable
    variable) =
                  case PathTemplateVariable -> PathTemplateEnv -> Maybe PathTemplate
    forall a b. Eq a => a -> [(a, b)] -> Maybe b
    lookup PathTemplateVariable
    variable PathTemplateEnv
    environment of
                      Just (PathTemplate [PathComponent]
    components) -> [PathComponent]
    components
                      Maybe PathTemplate
    Nothing                        -> [PathComponent
    component]

    -- | The initial environment has all the static stuff but no paths
    initialPathTemplateEnv :: PackageIdentifier
                           -> UnitId
                           -> CompilerInfo
                           -> Platform
                           -> PathTemplateEnv
    initialPathTemplateEnv :: PackageIdentifier
    -> UnitId -> CompilerInfo -> Platform -> PathTemplateEnv
    initialPathTemplateEnv PackageIdentifier
    pkgId UnitId
    libname CompilerInfo
    compiler Platform
    platform =
         PackageIdentifier -> UnitId -> PathTemplateEnv
    packageTemplateEnv  PackageIdentifier
    pkgId UnitId
    libname
      PathTemplateEnv -> PathTemplateEnv -> PathTemplateEnv
    forall a. [a] -> [a] -> [a]
    ++ CompilerInfo -> PathTemplateEnv
    compilerTemplateEnv CompilerInfo
    compiler
      PathTemplateEnv -> PathTemplateEnv -> PathTemplateEnv
    forall a. [a] -> [a] -> [a]
    ++ Platform -> PathTemplateEnv
    platformTemplateEnv Platform
    platform
      PathTemplateEnv -> PathTemplateEnv -> PathTemplateEnv
    forall a. [a] -> [a] -> [a]
    ++ CompilerInfo -> Platform -> PathTemplateEnv
    abiTemplateEnv CompilerInfo
    compiler Platform
    platform

    packageTemplateEnv :: PackageIdentifier -> UnitId -> PathTemplateEnv
    packageTemplateEnv :: PackageIdentifier -> UnitId -> PathTemplateEnv
    packageTemplateEnv PackageIdentifier
    pkgId UnitId
    uid =
      [(PathTemplateVariable
    PkgNameVar,  [PathComponent] -> PathTemplate
    PathTemplate [FilePath -> PathComponent
    Ordinary (FilePath -> PathComponent) -> FilePath -> PathComponent
    forall a b. (a -> b) -> a -> b
    $ PackageName -> FilePath
    forall a. Pretty a => a -> FilePath
    prettyShow (PackageIdentifier -> PackageName
    forall pkg. Package pkg => pkg -> PackageName
    packageName PackageIdentifier
    pkgId)])
      ,(PathTemplateVariable
    PkgVerVar,   [PathComponent] -> PathTemplate
    PathTemplate [FilePath -> PathComponent
    Ordinary (FilePath -> PathComponent) -> FilePath -> PathComponent
    forall a b. (a -> b) -> a -> b
    $ Version -> FilePath
    forall a. Pretty a => a -> FilePath
    prettyShow (PackageIdentifier -> Version
    forall pkg. Package pkg => pkg -> Version
    packageVersion PackageIdentifier
    pkgId)])
      -- Invariant: uid is actually a HashedUnitId.  Hard to enforce because
      -- it's an API change.
      ,(PathTemplateVariable
    LibNameVar,  [PathComponent] -> PathTemplate
    PathTemplate [FilePath -> PathComponent
    Ordinary (FilePath -> PathComponent) -> FilePath -> PathComponent
    forall a b. (a -> b) -> a -> b
    $ UnitId -> FilePath
    forall a. Pretty a => a -> FilePath
    prettyShow UnitId
    uid])
      ,(PathTemplateVariable
    PkgIdVar,    [PathComponent] -> PathTemplate
    PathTemplate [FilePath -> PathComponent
    Ordinary (FilePath -> PathComponent) -> FilePath -> PathComponent
    forall a b. (a -> b) -> a -> b
    $ PackageIdentifier -> FilePath
    forall a. Pretty a => a -> FilePath
    prettyShow PackageIdentifier
    pkgId])
      ]

    compilerTemplateEnv :: CompilerInfo -> PathTemplateEnv
    compilerTemplateEnv :: CompilerInfo -> PathTemplateEnv
    compilerTemplateEnv CompilerInfo
    compiler =
      [(PathTemplateVariable
    CompilerVar, [PathComponent] -> PathTemplate
    PathTemplate [FilePath -> PathComponent
    Ordinary (FilePath -> PathComponent) -> FilePath -> PathComponent
    forall a b. (a -> b) -> a -> b
    $ CompilerId -> FilePath
    forall a. Pretty a => a -> FilePath
    prettyShow (CompilerInfo -> CompilerId
    compilerInfoId CompilerInfo
    compiler)])
      ]

    platformTemplateEnv :: Platform -> PathTemplateEnv
    platformTemplateEnv :: Platform -> PathTemplateEnv
    platformTemplateEnv (Platform Arch
    arch OS
    os) =
      [(PathTemplateVariable
    OSVar,       [PathComponent] -> PathTemplate
    PathTemplate [FilePath -> PathComponent
    Ordinary (FilePath -> PathComponent) -> FilePath -> PathComponent
    forall a b. (a -> b) -> a -> b
    $ OS -> FilePath
    forall a. Pretty a => a -> FilePath
    prettyShow OS
    os])
      ,(PathTemplateVariable
    ArchVar,     [PathComponent] -> PathTemplate
    PathTemplate [FilePath -> PathComponent
    Ordinary (FilePath -> PathComponent) -> FilePath -> PathComponent
    forall a b. (a -> b) -> a -> b
    $ Arch -> FilePath
    forall a. Pretty a => a -> FilePath
    prettyShow Arch
    arch])
      ]

    abiTemplateEnv :: CompilerInfo -> Platform -> PathTemplateEnv
    abiTemplateEnv :: CompilerInfo -> Platform -> PathTemplateEnv
    abiTemplateEnv CompilerInfo
    compiler (Platform Arch
    arch OS
    os) =
      [(PathTemplateVariable
    AbiVar,      [PathComponent] -> PathTemplate
    PathTemplate [FilePath -> PathComponent
    Ordinary (FilePath -> PathComponent) -> FilePath -> PathComponent
    forall a b. (a -> b) -> a -> b
    $ Arch -> FilePath
    forall a. Pretty a => a -> FilePath
    prettyShow Arch
    arch FilePath -> ShowS
    forall a. [a] -> [a] -> [a]
    ++ Char
    '-'Char -> ShowS
    forall a. a -> [a] -> [a]
    :OS -> FilePath
    forall a. Pretty a => a -> FilePath
    prettyShow OS
    os FilePath -> ShowS
    forall a. [a] -> [a] -> [a]
    ++
                                              Char
    '-'Char -> ShowS
    forall a. a -> [a] -> [a]
    :CompilerId -> FilePath
    forall a. Pretty a => a -> FilePath
    prettyShow (CompilerInfo -> CompilerId
    compilerInfoId CompilerInfo
    compiler) FilePath -> ShowS
    forall a. [a] -> [a] -> [a]
    ++
                                              case CompilerInfo -> AbiTag
    compilerInfoAbiTag CompilerInfo
    compiler of
                                                AbiTag
    NoAbiTag   -> FilePath
    ""
                                                AbiTag FilePath
    tag -> Char
    '-'Char -> ShowS
    forall a. a -> [a] -> [a]
    :FilePath
    tag])
      ,(PathTemplateVariable
    AbiTagVar,   [PathComponent] -> PathTemplate
    PathTemplate [FilePath -> PathComponent
    Ordinary (FilePath -> PathComponent) -> FilePath -> PathComponent
    forall a b. (a -> b) -> a -> b
    $ AbiTag -> FilePath
    abiTagString (CompilerInfo -> AbiTag
    compilerInfoAbiTag CompilerInfo
    compiler)])
      ]

    installDirsTemplateEnv :: InstallDirs PathTemplate -> PathTemplateEnv
    installDirsTemplateEnv :: InstallDirTemplates -> PathTemplateEnv
    installDirsTemplateEnv InstallDirTemplates
    dirs =
      [(PathTemplateVariable
    PrefixVar,     InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    prefix     InstallDirTemplates
    dirs)
      ,(PathTemplateVariable
    BindirVar,     InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    bindir     InstallDirTemplates
    dirs)
      ,(PathTemplateVariable
    LibdirVar,     InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    libdir     InstallDirTemplates
    dirs)
      ,(PathTemplateVariable
    LibsubdirVar,  InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    libsubdir  InstallDirTemplates
    dirs)
      ,(PathTemplateVariable
    DynlibdirVar,  InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    dynlibdir  InstallDirTemplates
    dirs)
      ,(PathTemplateVariable
    DatadirVar,    InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    datadir    InstallDirTemplates
    dirs)
      ,(PathTemplateVariable
    DatasubdirVar, InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    datasubdir InstallDirTemplates
    dirs)
      ,(PathTemplateVariable
    DocdirVar,     InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    docdir     InstallDirTemplates
    dirs)
      ,(PathTemplateVariable
    HtmldirVar,    InstallDirTemplates -> PathTemplate
    forall dir. InstallDirs dir -> dir
    htmldir    InstallDirTemplates
    dirs)
      ]

    -- ---------------------------------------------------------------------------
    -- Parsing and showing path templates:

    -- The textual format is that of an ordinary Haskell String, eg
    -- "$prefix/bin"
    -- and this gets parsed to the internal representation as a sequence of path
    -- spans which are either strings or variables, eg:
    -- PathTemplate [Variable PrefixVar, Ordinary "/bin" ]

    instance Show PathTemplate where
      show :: PathTemplate -> FilePath
    show (PathTemplate [PathComponent]
    template) = ShowS
    forall a. Show a => a -> FilePath
    show ([PathComponent] -> FilePath
    forall a. Show a => a -> FilePath
    show [PathComponent]
    template)

    instance Read PathTemplate where
      readsPrec :: Int -> ReadS PathTemplate
    readsPrec Int
    p FilePath
    s = [ ([PathComponent] -> PathTemplate
    PathTemplate [PathComponent]
    template, FilePath
    s')
                      | (FilePath
    path, FilePath
    s')     <- Int -> ReadS FilePath
    forall a. Read a => Int -> ReadS a
    readsPrec Int
    p FilePath
    s
                      , ([PathComponent]
    template, FilePath
    "") <- ReadS [PathComponent]
    forall a. Read a => ReadS a
    reads FilePath
    path ]

    -- ---------------------------------------------------------------------------
    -- Internal utilities

    getWindowsProgramFilesDir :: IO FilePath
    getWindowsProgramFilesDir :: IO FilePath
    getWindowsProgramFilesDir = do
    #ifdef mingw32_HOST_OS
      m <- shGetFolderPath csidl_PROGRAM_FILES
    #else
      let m :: Maybe a
    m = Maybe a
    forall a. Maybe a
    Nothing
    #endif
      FilePath -> IO FilePath
    forall a. a -> IO a
    forall (m :: * -> *) a. Monad m => a -> m a
    return (FilePath -> Maybe FilePath -> FilePath
    forall a. a -> Maybe a -> a
    fromMaybe FilePath
    "C:\\Program Files" Maybe FilePath
    forall a. Maybe a
    m)

    #ifdef mingw32_HOST_OS
    shGetFolderPath :: CInt -> IO (Maybe FilePath)
    shGetFolderPath n =
      allocaArray long_path_size $ \pPath -> do
         r <- c_SHGetFolderPath nullPtr n nullPtr 0 pPath
         if (r /= 0)
            then return Nothing
            else do s <- peekCWString pPath; return (Just s)
      where
        long_path_size      = 1024 -- MAX_PATH is 260, this should be plenty

    csidl_PROGRAM_FILES :: CInt
    csidl_PROGRAM_FILES = 0x0026
    -- csidl_PROGRAM_FILES_COMMON :: CInt
    -- csidl_PROGRAM_FILES_COMMON = 0x002b

    #ifdef x86_64_HOST_ARCH
    #define CALLCONV ccall
    #else
    #define CALLCONV stdcall
    #endif

    foreign import CALLCONV unsafe "shlobj.h SHGetFolderPathW"
                c_SHGetFolderPath :: Ptr ()
                                  -> CInt
                                  -> Ptr ()
                                  -> CInt
                                  -> CWString
                                  -> Prelude.IO CInt
    #endif