diff options
| -rw-r--r-- | ghc/GHCi/UI.hs | 62 | ||||
| -rw-r--r-- | ghc/GHCi/UI/Monad.hs | 22 |
2 files changed, 66 insertions, 18 deletions
diff --git a/ghc/GHCi/UI.hs b/ghc/GHCi/UI.hs index d3c62e6c26..29f423869d 100644 --- a/ghc/GHCi/UI.hs +++ b/ghc/GHCi/UI.hs @@ -448,6 +448,7 @@ interactiveUI config srcs maybe_exprs = do default_editor <- liftIO $ findEditor eval_wrapper <- mkEvalWrapper default_progname default_args + let prelude_import = simpleImportDecl preludeModuleName startGHCi (runGHCi srcs maybe_exprs) GHCiState{ progname = default_progname, args = default_args, @@ -470,6 +471,8 @@ interactiveUI config srcs maybe_exprs = do cmdqueue = [], remembered_ctx = [], transient_ctx = [], + extra_imports = [], + prelude_imports = [prelude_import], ghc_e = isJust maybe_exprs, short_help = shortHelpText config, long_help = fullHelpText config, @@ -2315,13 +2318,33 @@ setGHCContextFromGHCiState = do -- the actual exception thrown by checkAdd, using tryBool to -- turn it into a Bool. iidecls <- filterM (tryBool.checkAdd) (transient_ctx st ++ remembered_ctx st) - dflags <- GHC.getSessionDynFlags - GHC.setContext $ - if xopt LangExt.ImplicitPrelude dflags && not (any isPreludeImport iidecls) - then iidecls ++ [implicitPreludeImport] - else iidecls - -- XXX put prel at the end, so that guessCurrentModule doesn't pick it up. + prel_iidecls <- getImplicitPreludeImports iidecls + valid_prel_iidecls <- filterM (tryBool . checkAdd) prel_iidecls + + extra_imports <- filterM (tryBool . checkAdd) (map IIDecl (extra_imports st)) + + GHC.setContext $ iidecls ++ extra_imports ++ valid_prel_iidecls + + +getImplicitPreludeImports :: [InteractiveImport] -> GHCi [InteractiveImport] +getImplicitPreludeImports iidecls = do + dflags <- GHC.getInteractiveDynFlags + -- allow :seti to override -XNoImplicitPrelude + st <- getGHCiState + + -- We add the prelude imports if there are no *-imports, and we also + -- allow each prelude import to be subsumed by another explicit import + -- of the same module. This means that you can override the prelude import + -- with "import Prelude hiding (map)", for example. + let prel_iidecls = + if xopt LangExt.ImplicitPrelude dflags && not (any isIIModule iidecls) + then [ IIDecl imp + | imp <- prelude_imports st + , not (any (sameImpModule imp) iidecls) ] + else [] + + return prel_iidecls -- ----------------------------------------------------------------------------- -- Utils on InteractiveImport @@ -2335,6 +2358,10 @@ mkIIDecl = IIDecl . simpleImportDecl iiModules :: [InteractiveImport] -> [ModuleName] iiModules is = [m | IIModule m <- is] +isIIModule :: InteractiveImport -> Bool +isIIModule (IIModule _) = True +isIIModule _ = False + iiModuleName :: InteractiveImport -> ModuleName iiModuleName (IIModule m) = m iiModuleName (IIDecl d) = unLoc (ideclName d) @@ -2342,12 +2369,9 @@ iiModuleName (IIDecl d) = unLoc (ideclName d) preludeModuleName :: ModuleName preludeModuleName = GHC.mkModuleName "Prelude" -implicitPreludeImport :: InteractiveImport -implicitPreludeImport = IIDecl (simpleImportDecl preludeModuleName) - -isPreludeImport :: InteractiveImport -> Bool -isPreludeImport (IIModule {}) = True -isPreludeImport (IIDecl d) = unLoc (ideclName d) == preludeModuleName +sameImpModule :: ImportDecl RdrName -> InteractiveImport -> Bool +sameImpModule _ (IIModule _) = False -- we only care about imports here +sameImpModule imp (IIDecl d) = unLoc (ideclName d) == unLoc (ideclName imp) addNotSubsumed :: InteractiveImport -> [InteractiveImport] -> [InteractiveImport] @@ -2765,15 +2789,17 @@ showImports = do = ":module +*" ++ moduleNameString star_m show_one (IIDecl imp) = showPpr dflags imp - prel_imp - | any isPreludeImport (rem_ctx ++ trans_ctx) = [] - | not (xopt LangExt.ImplicitPrelude dflags) = [] - | otherwise = ["import Prelude -- implicit"] + prel_iidecls <- getImplicitPreludeImports (rem_ctx ++ trans_ctx) + + let show_prel p = show_one p ++ " -- implicit" + show_extra p = show_one (IIDecl p) ++ " -- fixed" trans_comment s = s ++ " -- added automatically" :: String -- - liftIO $ mapM_ putStrLn (prel_imp ++ map show_one rem_ctx - ++ map (trans_comment . show_one) trans_ctx) + liftIO $ mapM_ putStrLn (map show_one rem_ctx ++ + map (trans_comment . show_one) trans_ctx ++ + map show_prel prel_iidecls ++ + map show_extra (extra_imports st)) showModules :: GHCi () showModules = do diff --git a/ghc/GHCi/UI/Monad.hs b/ghc/GHCi/UI/Monad.hs index 260d92c008..244595b8b0 100644 --- a/ghc/GHCi/UI/Monad.hs +++ b/ghc/GHCi/UI/Monad.hs @@ -44,6 +44,8 @@ import SrcLoc import Module import GHCi import GHCi.RemoteTypes +import HsSyn (ImportDecl) +import RdrName (RdrName) import Exception import Numeric @@ -106,6 +108,26 @@ data GHCiState = GHCiState -- :load, :reload, and :add. In between it may be modified -- by :module. + extra_imports :: [ImportDecl RdrName], + -- ^ These are "always-on" imports, added to the + -- context regardless of what other imports we have. + -- This is useful for adding imports that are required + -- by setGHCiMonad. Be careful adding things here: + -- you can create ambiguities if these imports overlap + -- with other things in scope. + -- + -- NB. although this is not currently used by GHCi itself, + -- it was added to support other front-ends that are based + -- on the GHCi code. Potentially we could also expose + -- this functionality via GHCi commands. + + prelude_imports :: [ImportDecl RdrName], + -- ^ These imports are added to the context when + -- -XImplicitPrelude is on and we don't have a *-module + -- in the context. They can also be overridden by another + -- import for the same module, e.g. + -- "import Prelude hiding (map)" + ghc_e :: Bool, -- ^ True if this is 'ghc -e' (or runghc) short_help :: String, |