\begin{code}
module Finder (
- initFinder, -- :: [PackageConfig] -> IO (),
- findModule, -- :: ModuleName -> IO (Maybe (Module, ModLocation))
- findModuleDep, -- :: ModuleName -> Bool -> IO (Maybe (Module, ModLocation))
- findPackageModule, -- :: ModuleName -> IO (Maybe (Module, ModLocation))
- mkHomeModuleLocn, -- :: ModuleName -> String -> FilePath
- -- -> IO ModLocation
- emptyHomeDirCache, -- :: IO ()
- flushPackageCache -- :: [PackageConfig] -> IO ()
+ flushFinderCache, -- :: IO ()
+ FindResult(..),
+ findModule, -- :: ModuleName -> Bool -> IO FindResult
+ findPackageModule, -- :: ModuleName -> Bool -> IO FindResult
+ mkHomeModLocation, -- :: ModuleName -> FilePath -> IO ModLocation
+ mkHomeModLocation2, -- :: ModuleName -> FilePath -> String -> IO ModLocation
+ addHomeModuleToFinder, -- :: HscEnv -> Module -> ModLocation -> IO ()
+ uncacheModule, -- :: HscEnv -> Module -> IO ()
+ mkStubPaths,
+
+ findObjectLinkableMaybe,
+ findObjectLinkable,
+
+ cantFindError, -- :: DynFlags -> Module -> FindResult -> SDoc
) where
#include "HsVersions.h"
-import Module ( Module, ModLocation(..), ModuleName,
- moduleNameUserString, mkHomeModule, mkPackageModule
- )
-import Packages ( PackageConfig(..) )
-import DriverPhases
-import DriverState
-import DriverUtil
+import Module
+import UniqFM ( filterUFM, delFromUFM )
+import HscTypes
+import Packages
import FastString
-import Config
+import Util
+import DynFlags ( DynFlags(..), isOneShot, GhcMode(..) )
+import Outputable
+import Maybes ( expectJust )
+
+import DATA_IOREF ( IORef, writeIORef, readIORef )
+
+import Data.List
+import System.Directory
+import System.IO
+import Control.Monad
+import Data.Maybe ( isNothing )
+import Time ( ClockTime )
+
+
+type FileExt = String -- Filename extension
+type BaseName = String -- Basename of file
+
+-- -----------------------------------------------------------------------------
+-- The Finder
+
+-- The Finder provides a thin filesystem abstraction to the rest of
+-- the compiler. For a given module, it can tell you where the
+-- source, interface, and object files for that module live.
+
+-- It does *not* know which particular package a module lives in. Use
+-- Packages.lookupModuleInAllPackages for that.
+
+-- -----------------------------------------------------------------------------
+-- The finder's cache
+
+-- remove all the home modules from the cache; package modules are
+-- assumed to not move around during a session.
+flushFinderCache :: IORef FinderCache -> IO ()
+flushFinderCache finder_cache = do
+ fm <- readIORef finder_cache
+ writeIORef finder_cache $! filterUFM (\(loc,m) -> isNothing m) fm
+
+addToFinderCache :: IORef FinderCache -> Module -> FinderCacheEntry -> IO ()
+addToFinderCache finder_cache mod_name entry = do
+ fm <- readIORef finder_cache
+ writeIORef finder_cache $! extendModuleEnv fm mod_name entry
+
+removeFromFinderCache :: IORef FinderCache -> Module -> IO ()
+removeFromFinderCache finder_cache mod_name = do
+ fm <- readIORef finder_cache
+ writeIORef finder_cache $! delFromUFM fm mod_name
+
+lookupFinderCache :: IORef FinderCache -> Module -> IO (Maybe FinderCacheEntry)
+lookupFinderCache finder_cache mod_name = do
+ fm <- readIORef finder_cache
+ return $! lookupModuleEnv fm mod_name
+
+-- -----------------------------------------------------------------------------
+-- The two external entry points
+
+-- This is the main interface to the finder, which maps ModuleNames to
+-- Modules and ModLocations.
+--
+-- The Module contains one crucial bit of information about a module:
+-- whether it lives in the current ("home") package or not (see Module
+-- for more details).
+--
+-- The ModLocation contains the names of all the files associated with
+-- that module: its source file, .hi file, object file, etc.
+
+data FindResult
+ = Found ModLocation PackageIdH
+ -- the module was found
+ | FoundMultiple [PackageId]
+ -- *error*: both in multiple packages
+ | PackageHidden PackageId
+ -- for an explicit source import: the package containing the module is
+ -- not exposed.
+ | ModuleHidden PackageId
+ -- for an explicit source import: the package containing the module is
+ -- exposed, but the module itself is hidden.
+ | NotFound [FilePath]
+ -- the module was not found, the specified places were searched.
+
+findModule :: HscEnv -> Module -> Bool -> IO FindResult
+findModule = findModule' True
+
+findPackageModule :: HscEnv -> Module -> Bool -> IO FindResult
+findPackageModule = findModule' False
+
+
+data LocalFindResult
+ = Ok FinderCacheEntry
+ | CantFindAmongst [FilePath]
+ | MultiplePackages [PackageId]
+
+findModule' :: Bool -> HscEnv -> Module -> Bool -> IO FindResult
+findModule' home_allowed hsc_env name explicit
+ = do -- First try the cache
+ mb_entry <- lookupFinderCache cache name
+ case mb_entry of
+ Just old_entry -> return $! found old_entry
+ Nothing -> not_cached
-import DATA_IOREF ( readIORef )
-
-import List
-import Directory
-import IO
-import Monad
-\end{code}
-
-The Finder provides a thin filesystem abstraction to the rest of the
-compiler. For a given module, it knows (a) whether the module lives
-in the home package or in another package, so it can make a Module
-from a ModuleName, and (b) where the source, interface, and object
-files for a module live.
-
-It does *not* know which particular package a module lives in, because
-that information is only contained in the interface file.
-
-\begin{code}
-initFinder :: [PackageConfig] -> IO ()
-initFinder pkgs = return ()
-
--- empty, and lazilly fill in the package cache
-flushPackageCache :: [PackageConfig] -> IO ()
-flushPackageCache pkgs = return ()
-
-emptyHomeDirCache :: IO ()
-emptyHomeDirCache = return ()
-
-findModule :: ModuleName -> IO (Maybe (Module, ModLocation))
-findModule name = findModuleDep name False
-
-findModuleDep :: ModuleName -> Bool -> IO (Maybe (Module, ModLocation))
-findModuleDep name is_source
- = do { j <- maybeHomeModule name is_source
- ; case j of
- Just home_module -> return (Just home_module)
- Nothing -> findPackageMod name False is_source
- }
-
-maybeHomeModule :: ModuleName -> Bool -> IO (Maybe (Module, ModLocation))
-maybeHomeModule mod_name is_source = do
- home_path <- readIORef v_Import_paths
- hisuf <- readIORef v_Hi_suf
- mode <- readIORef v_GhcMode
-
- let mod_str = moduleNameUserString mod_name
- basename = map (\c -> if c == '.' then '/' else c) mod_str
-
- -- In compilation manager modes, we look for source files in the home
- -- package because we can compile these automatically. In one-shot
- -- compilation mode we look for .hi files only.
- --
- -- When generating dependencies, we're interested in either category.
- --
- source_exts =
- [ ("hs", \ fName path -> mkHomeModuleLocn mod_name path fName)
- , ("lhs", \ fName path -> mkHomeModuleLocn mod_name path fName)
- ]
- hi_exts = [ (hisuf, \ fName path -> mkHiOnlyModuleLocn mod_name fName) ]
-
- std_exts
- | mode == DoMkDependHS = hi_exts ++ source_exts
- | isCompManagerMode mode = source_exts
- | otherwise = hi_exts
-
- -- last chance: .hi-boot-<ver> and .hi-boot
- hi_boot_ver = "hi-boot-" ++ cHscIfaceFileVersion
-
- boot_exts =
- [ (hi_boot_ver, \ fName path -> mkHiOnlyModuleLocn mod_name fName)
- , ("hi-boot", \ fName path -> mkHiOnlyModuleLocn mod_name fName)
- ]
-
- searchPathExts home_path basename
- (if is_source then boot_exts else (std_exts ++ boot_exts))
- -- for SOURCE imports, check the hi-boot extensions
- -- before the source/iface ones, to avoid
- -- creating circ Makefile deps.
-
-
-mkHiOnlyModuleLocn mod_name hi_file =
- return
- ( mkHomeModule mod_name
- , ModLocation{ ml_hspp_file = Nothing
- , ml_hs_file = Nothing
- , ml_hi_file = hi_file
- , ml_obj_file = Nothing
- }
- )
-
--- The .hi file always follows the module name, whereas the object
--- file may follow the name of the source file in the case where the
--- two differ (see summariseFile in compMan/CompManager.lhs).
-
-mkHomeModuleLocn mod_name
- basename -- everything but the extension
- source_fn -- full path to the source (required)
- = do
-
- hisuf <- readIORef v_Hi_suf
- hidir <- readIORef v_Hi_dir
-
- -- take the *last* component of the module name (if a hierarchical name),
- -- and append it to the directory to get the .hi file name.
- let (_,mod_str) = split_longest_prefix (moduleNameUserString mod_name) (=='.')
- hi_filename = mod_str ++ '.':hisuf
- hi_path | Just d <- hidir = d
- | otherwise = getdir basename
- hi = hi_path ++ '/':hi_filename
-
- -- figure out the .o file name. It also lives in the same dir
- -- as the source, but can be overriden by a -odir flag.
- o_file <- odir_ify (basename ++ '.':phaseInputExt Ln) >>= osuf_ify
-
- return (mkHomeModule mod_name,
- ModLocation{ ml_hspp_file = Nothing
- , ml_hs_file = Just source_fn
- , ml_hi_file = hi
- , ml_obj_file = Just o_file
- })
-
-findPackageMod :: ModuleName
- -> Bool
- -> Bool
- -> IO (Maybe (Module, ModLocation))
-findPackageMod mod_name hiOnly is_source = do
- pkgs <- getPackageInfo
-
- -- hi-suffix for packages depends on the build tag.
- package_hisuf <-
- do tag <- readIORef v_Build_tag
- if null tag
- then return "hi"
- else return (tag ++ "_hi")
- let imp_dirs = concatMap import_dirs pkgs
- mod_str = moduleNameUserString mod_name
- basename = map (\c -> if c == '.' then '/' else c) mod_str
-
- retPackageModule mod_name mbFName path =
- return ( mkPackageModule mod_name
- , ModLocation{ ml_hspp_file = Nothing
- , ml_hs_file = mbFName
- , ml_hi_file = path ++ '.':package_hisuf
- , ml_obj_file = Nothing
- })
-
- -- last chance: .hi-boot-<ver> and .hi-boot
- hi_boot_ver = "hi-boot-" ++ cHscIfaceFileVersion
-
- boot_exts =
- [ (hi_boot_ver, \ fName path -> mkHiOnlyModuleLocn mod_name fName)
- , ("hi-boot", \ fName path -> mkHiOnlyModuleLocn mod_name fName)
- ]
-
- searchPathExts
- imp_dirs basename
- (if is_source then boot_exts else
- ((package_hisuf,\ fName path -> retPackageModule mod_name Nothing path) :
- (if hiOnly then [] else
- [ ("hs", \ fName path -> retPackageModule mod_name (Just fName) path)
- , ("lhs", \ fName path -> retPackageModule mod_name (Just fName) path)
- ])))
where
+ cache = hsc_FC hsc_env
+ dflags = hsc_dflags hsc_env
+
+ -- We've found the module, so the remaining question is
+ -- whether it's visible or not
+ found :: FinderCacheEntry -> FindResult
+ found (loc, Nothing)
+ | home_allowed = Found loc HomePackage
+ | otherwise = NotFound []
+ found (loc, Just (pkg, exposed_mod))
+ | explicit && not exposed_mod = ModuleHidden pkg_name
+ | explicit && not (exposed pkg) = PackageHidden pkg_name
+ | otherwise =
+ Found loc (ExtPackage (mkPackageId (package pkg)))
+ where
+ pkg_name = packageConfigId pkg
+
+ found_new entry = do
+ addToFinderCache cache name entry
+ return $! found entry
+
+ not_cached
+ | not home_allowed = do
+ j <- findPackageModule' dflags name
+ case j of
+ Ok entry -> found_new entry
+ MultiplePackages pkgs -> return (FoundMultiple pkgs)
+ CantFindAmongst paths -> return (NotFound paths)
+
+ | otherwise = do
+ j <- findHomeModule' dflags name
+ case j of
+ Ok entry -> found_new entry
+ MultiplePackages pkgs -> return (FoundMultiple pkgs)
+ CantFindAmongst home_files -> do
+ r <- findPackageModule' dflags name
+ case r of
+ CantFindAmongst pkg_files ->
+ return (NotFound (home_files ++ pkg_files))
+ MultiplePackages pkgs ->
+ return (FoundMultiple pkgs)
+ Ok entry ->
+ found_new entry
+
+addHomeModuleToFinder :: HscEnv -> Module -> ModLocation -> IO ()
+addHomeModuleToFinder hsc_env mod loc
+ = addToFinderCache (hsc_FC hsc_env) mod (loc, Nothing)
+
+uncacheModule :: HscEnv -> Module -> IO ()
+uncacheModule hsc_env mod = removeFromFinderCache (hsc_FC hsc_env) mod
+
+-- -----------------------------------------------------------------------------
+-- The internal workers
+
+findHomeModule' :: DynFlags -> Module -> IO LocalFindResult
+findHomeModule' dflags mod = do
+ let home_path = importPaths dflags
+ hisuf = hiSuf dflags
+
+ let
+ source_exts =
+ [ ("hs", mkHomeModLocationSearched dflags mod "hs")
+ , ("lhs", mkHomeModLocationSearched dflags mod "lhs")
+ ]
+
+ hi_exts = [ (hisuf, mkHiOnlyModLocation dflags hisuf)
+ , (addBootSuffix hisuf, mkHiOnlyModLocation dflags hisuf)
+ ]
+
+ -- In compilation manager modes, we look for source files in the home
+ -- package because we can compile these automatically. In one-shot
+ -- compilation mode we look for .hi and .hi-boot files only.
+ exts | isOneShot (ghcMode dflags) = hi_exts
+ | otherwise = source_exts
+
+ searchPathExts home_path mod exts
+
+findPackageModule' :: DynFlags -> Module -> IO LocalFindResult
+findPackageModule' dflags mod
+ = case lookupModuleInAllPackages dflags mod of
+ [] -> return (CantFindAmongst [])
+ [pkg_info] -> findPackageIface dflags mod pkg_info
+ many -> return (MultiplePackages (map (mkPackageId.package.fst) many))
+
+findPackageIface :: DynFlags -> Module -> (PackageConfig,Bool) -> IO LocalFindResult
+findPackageIface dflags mod pkg_info@(pkg_conf, _) = do
+ let
+ tag = buildTag dflags
+
+ -- hi-suffix for packages depends on the build tag.
+ package_hisuf | null tag = "hi"
+ | otherwise = tag ++ "_hi"
+ hi_exts =
+ [ (package_hisuf,
+ mkPackageModLocation dflags pkg_info package_hisuf) ]
+
+ source_exts =
+ [ ("hs", mkPackageModLocation dflags pkg_info package_hisuf)
+ , ("lhs", mkPackageModLocation dflags pkg_info package_hisuf)
+ ]
+
+ -- mkdependHS needs to look for source files in packages too, so
+ -- that we can make dependencies between package before they have
+ -- been built.
+ exts
+ | MkDepend <- ghcMode dflags = hi_exts ++ source_exts
+ | otherwise = hi_exts
+ -- we never look for a .hi-boot file in an external package;
+ -- .hi-boot files only make sense for the home package.
+
+ searchPathExts (importDirs pkg_conf) mod exts
+
+-- -----------------------------------------------------------------------------
+-- General path searching
+
+searchPathExts
+ :: [FilePath] -- paths to search
+ -> Module -- module name
+ -> [ (
+ FileExt, -- suffix
+ FilePath -> BaseName -> IO FinderCacheEntry -- action
+ )
+ ]
+ -> IO LocalFindResult
+
+searchPathExts paths mod exts
+ = do result <- search to_search
+{-
+ hPutStrLn stderr (showSDoc $
+ vcat [text "Search" <+> ppr mod <+> sep (map (text. fst) exts)
+ , nest 2 (vcat (map text paths))
+ , case result of
+ Succeeded (loc, p) -> text "Found" <+> ppr loc
+ Failed fs -> text "not found"])
+-}
+ return result
-findPackageModule :: ModuleName -> IO (Maybe (Module, ModLocation))
-findPackageModule mod_name = findPackageMod mod_name True False
-
-searchPathExts :: [FilePath]
- -> String
- -> [(String, FilePath -> String -> IO (Module, ModLocation))]
- -> IO (Maybe (Module, ModLocation))
-searchPathExts path basename exts = search path
where
- search [] = return Nothing
- search (p:ps) = loop exts
- where
- base | p == "." = basename
- | otherwise = p ++ '/':basename
-
- loop [] = search ps
- loop ((ext,fn):exts) = do
- let file = base ++ '.':ext
- b <- doesFileExist file
- if b then Just `liftM` fn file base
- else loop exts
+ basename = dots_to_slashes (moduleString mod)
+
+ to_search :: [(FilePath, IO FinderCacheEntry)]
+ to_search = [ (file, fn path basename)
+ | path <- paths,
+ (ext,fn) <- exts,
+ let base | path == "." = basename
+ | otherwise = path `joinFileName` basename
+ file = base `joinFileExt` ext
+ ]
+
+ search [] = return (CantFindAmongst (map fst to_search))
+ search ((file, mk_result) : rest) = do
+ b <- doesFileExist file
+ if b
+ then do { res <- mk_result; return (Ok res) }
+ else search rest
+
+mkHomeModLocationSearched :: DynFlags -> Module -> FileExt
+ -> FilePath -> BaseName -> IO FinderCacheEntry
+mkHomeModLocationSearched dflags mod suff path basename = do
+ loc <- mkHomeModLocation2 dflags mod (path `joinFileName` basename) suff
+ return (loc, Nothing)
+
+mkHiOnlyModLocation :: DynFlags -> FileExt -> FilePath -> BaseName
+ -> IO FinderCacheEntry
+mkHiOnlyModLocation dflags hisuf path basename = do
+ loc <- hiOnlyModLocation dflags path basename hisuf
+ return (loc, Nothing)
+
+mkPackageModLocation :: DynFlags -> (PackageConfig, Bool) -> FileExt
+ -> FilePath -> BaseName -> IO FinderCacheEntry
+mkPackageModLocation dflags pkg_info hisuf path basename = do
+ loc <- hiOnlyModLocation dflags path basename hisuf
+ return (loc, Just pkg_info)
+
+-- -----------------------------------------------------------------------------
+-- Constructing a home module location
+
+-- This is where we construct the ModLocation for a module in the home
+-- package, for which we have a source file. It is called from three
+-- places:
+--
+-- (a) Here in the finder, when we are searching for a module to import,
+-- using the search path (-i option).
+--
+-- (b) The compilation manager, when constructing the ModLocation for
+-- a "root" module (a source file named explicitly on the command line
+-- or in a :load command in GHCi).
+--
+-- (c) The driver in one-shot mode, when we need to construct a
+-- ModLocation for a source file named on the command-line.
+--
+-- Parameters are:
+--
+-- mod
+-- The name of the module
+--
+-- path
+-- (a): The search path component where the source file was found.
+-- (b) and (c): "."
+--
+-- src_basename
+-- (a): dots_to_slashes (moduleNameUserString mod)
+-- (b) and (c): The filename of the source file, minus its extension
+--
+-- ext
+-- The filename extension of the source file (usually "hs" or "lhs").
+
+mkHomeModLocation :: DynFlags -> Module -> FilePath -> IO ModLocation
+mkHomeModLocation dflags mod src_filename = do
+ let (basename,extension) = splitFilename src_filename
+ mkHomeModLocation2 dflags mod basename extension
+
+mkHomeModLocation2 :: DynFlags
+ -> Module
+ -> FilePath -- Of source module, without suffix
+ -> String -- Suffix
+ -> IO ModLocation
+mkHomeModLocation2 dflags mod src_basename ext = do
+ let mod_basename = dots_to_slashes (moduleString mod)
+
+ obj_fn <- mkObjPath dflags src_basename mod_basename
+ hi_fn <- mkHiPath dflags src_basename mod_basename
+
+ return (ModLocation{ ml_hs_file = Just (src_basename `joinFileExt` ext),
+ ml_hi_file = hi_fn,
+ ml_obj_file = obj_fn })
+
+hiOnlyModLocation :: DynFlags -> FilePath -> String -> Suffix -> IO ModLocation
+hiOnlyModLocation dflags path basename hisuf
+ = do let full_basename = path `joinFileName` basename
+ obj_fn <- mkObjPath dflags full_basename basename
+ return ModLocation{ ml_hs_file = Nothing,
+ ml_hi_file = full_basename `joinFileExt` hisuf,
+ -- Remove the .hi-boot suffix from
+ -- hi_file, if it had one. We always
+ -- want the name of the real .hi file
+ -- in the ml_hi_file field.
+ ml_obj_file = obj_fn
+ }
+
+-- | Constructs the filename of a .o file for a given source file.
+-- Does /not/ check whether the .o file exists
+mkObjPath
+ :: DynFlags
+ -> FilePath -- the filename of the source file, minus the extension
+ -> String -- the module name with dots replaced by slashes
+ -> IO FilePath
+mkObjPath dflags basename mod_basename
+ = do let
+ odir = objectDir dflags
+ osuf = objectSuf dflags
+
+ obj_basename | Just dir <- odir = dir `joinFileName` mod_basename
+ | otherwise = basename
+
+ return (obj_basename `joinFileExt` osuf)
+
+-- | Constructs the filename of a .hi file for a given source file.
+-- Does /not/ check whether the .hi file exists
+mkHiPath
+ :: DynFlags
+ -> FilePath -- the filename of the source file, minus the extension
+ -> String -- the module name with dots replaced by slashes
+ -> IO FilePath
+mkHiPath dflags basename mod_basename
+ = do let
+ hidir = hiDir dflags
+ hisuf = hiSuf dflags
+
+ hi_basename | Just dir <- hidir = dir `joinFileName` mod_basename
+ | otherwise = basename
+
+ return (hi_basename `joinFileExt` hisuf)
+
+
+-- -----------------------------------------------------------------------------
+-- Filenames of the stub files
+
+-- We don't have to store these in ModLocations, because they can be derived
+-- from other available information, and they're only rarely needed.
+
+mkStubPaths
+ :: DynFlags
+ -> Module
+ -> ModLocation
+ -> (FilePath,FilePath)
+
+mkStubPaths dflags mod location
+ = let
+ stubdir = stubDir dflags
+
+ mod_basename = dots_to_slashes (moduleString mod)
+ src_basename = basenameOf (expectJust "mkStubPaths"
+ (ml_hs_file location))
+
+ stub_basename0
+ | Just dir <- stubdir = dir `joinFileName` mod_basename
+ | otherwise = src_basename
+
+ stub_basename = stub_basename0 ++ "_stub"
+ in
+ (stub_basename `joinFileExt` "c",
+ stub_basename `joinFileExt` "h")
+ -- the _stub.o filename is derived from the ml_obj_file.
+
+-- -----------------------------------------------------------------------------
+-- findLinkable isn't related to the other stuff in here,
+-- but there's no other obvious place for it
+
+findObjectLinkableMaybe :: Module -> ModLocation -> IO (Maybe Linkable)
+findObjectLinkableMaybe mod locn
+ = do let obj_fn = ml_obj_file locn
+ maybe_obj_time <- modificationTimeIfExists obj_fn
+ case maybe_obj_time of
+ Nothing -> return Nothing
+ Just obj_time -> liftM Just (findObjectLinkable mod obj_fn obj_time)
+
+-- Make an object linkable when we know the object file exists, and we know
+-- its modification time.
+findObjectLinkable :: Module -> FilePath -> ClockTime -> IO Linkable
+findObjectLinkable mod obj_fn obj_time = do
+ let stub_fn = case splitFilename3 obj_fn of
+ (dir, base, ext) -> dir ++ "/" ++ base ++ "_stub.o"
+ stub_exist <- doesFileExist stub_fn
+ if stub_exist
+ then return (LM obj_time mod [DotO obj_fn, DotO stub_fn])
+ else return (LM obj_time mod [DotO obj_fn])
+
+-- -----------------------------------------------------------------------------
+-- Utils
+
+dots_to_slashes = map (\c -> if c == '.' then '/' else c)
+
+
+-- -----------------------------------------------------------------------------
+-- Error messages
+
+cantFindError :: DynFlags -> Module -> FindResult -> SDoc
+cantFindError dflags mod_name (FoundMultiple pkgs)
+ = hang (ptext SLIT("Cannot import") <+> quotes (ppr mod_name) <> colon) 2 (
+ sep [ptext SLIT("it was found in multiple packages:"),
+ hsep (map (text.packageIdString) pkgs)]
+ )
+cantFindError dflags mod_name find_result
+ = hang (ptext SLIT("Could not find module") <+> quotes (ppr mod_name) <> colon)
+ 2 more_info
+ where
+ more_info
+ = case find_result of
+ PackageHidden pkg
+ -> ptext SLIT("it is a member of package") <+> ppr pkg <> comma
+ <+> ptext SLIT("which is hidden")
+
+ ModuleHidden pkg
+ -> ptext SLIT("it is hidden") <+> parens (ptext SLIT("in package")
+ <+> ppr pkg)
+
+ NotFound files
+ | null files
+ -> ptext SLIT("it is not a module in the current program, or in any known package.")
+ | verbosity dflags < 3
+ -> ptext SLIT("use -v to see a list of the files searched for")
+ | otherwise
+ -> hang (ptext SLIT("locations searched:"))
+ 2 (vcat (map text files))
+
+ _ -> panic "cantFindErr"
\end{code}