ghc-8.6.4: main/InteractiveEval.hs
{-# LANGUAGE CPP, MagicHash, NondecreasingIndentation, UnboxedTuples,
RecordWildCards, BangPatterns #-}
-- -----------------------------------------------------------------------------
--
-- (c) The University of Glasgow, 2005-2007
--
-- Running statements interactively
--
-- -----------------------------------------------------------------------------
module InteractiveEval (
Resume(..), History(..),
execStmt, ExecOptions(..), execOptions, ExecResult(..), resumeExec,
runDecls, runDeclsWithLocation,
isStmt, hasImport, isImport, isDecl,
parseImportDecl, SingleStep(..),
abandon, abandonAll,
getResumeContext,
getHistorySpan,
getModBreaks,
getHistoryModule,
back, forward,
setContext, getContext,
availsToGlobalRdrEnv,
getNamesInScope,
getRdrNamesInScope,
moduleIsInterpreted,
getInfo,
exprType,
typeKind,
parseName,
getDocs,
GetDocsFailure(..),
showModule,
moduleIsBootOrNotObjectLinkable,
parseExpr, compileParsedExpr,
compileExpr, dynCompileExpr,
compileExprRemote, compileParsedExprRemote,
Term(..), obtainTermFromId, obtainTermFromVal, reconstructType
) where
#include "HsVersions.h"
import GhcPrelude
import InteractiveEvalTypes
import GHCi
import GHCi.Message
import GHCi.RemoteTypes
import GhcMonad
import HscMain
import HsSyn
import HscTypes
import InstEnv
import IfaceEnv ( newInteractiveBinder )
import FamInstEnv ( FamInst )
import CoreFVs ( orphNamesOfFamInst )
import TyCon
import Type hiding( typeKind )
import RepType
import TcType hiding( typeKind )
import Var
import Id
import Name hiding ( varName )
import NameSet
import Avail
import RdrName
import VarEnv
import ByteCodeTypes
import Linker
import DynFlags
import Unique
import UniqSupply
import MonadUtils
import Module
import PrelNames ( toDynName, pretendNameIsInScope )
import TysWiredIn ( isCTupleTyConName )
import Panic
import Maybes
import ErrUtils
import SrcLoc
import RtClosureInspect
import Outputable
import FastString
import Bag
import Util
import qualified Lexer (P (..), ParseResult(..), unP, mkPState)
import qualified Parser (parseStmt, parseModule, parseDeclaration, parseImport)
import System.Directory
import Data.Dynamic
import Data.Either
import qualified Data.IntMap as IntMap
import Data.List (find,intercalate)
import Data.Map (Map)
import qualified Data.Map as Map
import StringBuffer (stringToStringBuffer)
import Control.Monad
import GHC.Exts
import Data.Array
import Exception
-- -----------------------------------------------------------------------------
-- running a statement interactively
getResumeContext :: GhcMonad m => m [Resume]
getResumeContext = withSession (return . ic_resume . hsc_IC)
mkHistory :: HscEnv -> ForeignHValue -> BreakInfo -> History
mkHistory hsc_env hval bi = History hval bi (findEnclosingDecls hsc_env bi)
getHistoryModule :: History -> Module
getHistoryModule = breakInfo_module . historyBreakInfo
getHistorySpan :: HscEnv -> History -> SrcSpan
getHistorySpan hsc_env History{..} =
let BreakInfo{..} = historyBreakInfo in
case lookupHpt (hsc_HPT hsc_env) (moduleName breakInfo_module) of
Just hmi -> modBreaks_locs (getModBreaks hmi) ! breakInfo_number
_ -> panic "getHistorySpan"
getModBreaks :: HomeModInfo -> ModBreaks
getModBreaks hmi
| Just linkable <- hm_linkable hmi,
[BCOs cbc _] <- linkableUnlinked linkable
= fromMaybe emptyModBreaks (bc_breaks cbc)
| otherwise
= emptyModBreaks -- probably object code
{- | Finds the enclosing top level function name -}
-- ToDo: a better way to do this would be to keep hold of the decl_path computed
-- by the coverage pass, which gives the list of lexically-enclosing bindings
-- for each tick.
findEnclosingDecls :: HscEnv -> BreakInfo -> [String]
findEnclosingDecls hsc_env (BreakInfo modl ix) =
let hmi = expectJust "findEnclosingDecls" $
lookupHpt (hsc_HPT hsc_env) (moduleName modl)
mb = getModBreaks hmi
in modBreaks_decls mb ! ix
-- | Update fixity environment in the current interactive context.
updateFixityEnv :: GhcMonad m => FixityEnv -> m ()
updateFixityEnv fix_env = do
hsc_env <- getSession
let ic = hsc_IC hsc_env
setSession $ hsc_env { hsc_IC = ic { ic_fix_env = fix_env } }
-- -----------------------------------------------------------------------------
-- execStmt
-- | default ExecOptions
execOptions :: ExecOptions
execOptions = ExecOptions
{ execSingleStep = RunToCompletion
, execSourceFile = "<interactive>"
, execLineNumber = 1
, execWrap = EvalThis -- just run the statement, don't wrap it in anything
}
-- | Run a statement in the current interactive context.
execStmt
:: GhcMonad m
=> String -- ^ a statement (bind or expression)
-> ExecOptions
-> m ExecResult
execStmt stmt ExecOptions{..} = do
hsc_env <- getSession
-- Turn off -fwarn-unused-local-binds when running a statement, to hide
-- warnings about the implicit bindings we introduce.
let ic = hsc_IC hsc_env -- use the interactive dflags
idflags' = ic_dflags ic `wopt_unset` Opt_WarnUnusedLocalBinds
hsc_env' = hsc_env{ hsc_IC = ic{ ic_dflags = idflags' } }
-- compile to value (IO [HValue]), don't run
r <- liftIO $ hscStmtWithLocation hsc_env' stmt
execSourceFile execLineNumber
case r of
-- empty statement / comment
Nothing -> return (ExecComplete (Right []) 0)
Just (ids, hval, fix_env) -> do
updateFixityEnv fix_env
status <-
withVirtualCWD $
liftIO $
evalStmt hsc_env' (isStep execSingleStep) (execWrap hval)
let ic = hsc_IC hsc_env
bindings = (ic_tythings ic, ic_rn_gbl_env ic)
size = ghciHistSize idflags'
handleRunStatus execSingleStep stmt bindings ids
status (emptyHistory size)
runDecls :: GhcMonad m => String -> m [Name]
runDecls = runDeclsWithLocation "<interactive>" 1
-- | Run some declarations and return any user-visible names that were brought
-- into scope.
runDeclsWithLocation :: GhcMonad m => String -> Int -> String -> m [Name]
runDeclsWithLocation source linenumber expr =
do
hsc_env <- getSession
(tyThings, ic) <- liftIO $ hscDeclsWithLocation hsc_env expr source linenumber
setSession $ hsc_env { hsc_IC = ic }
hsc_env <- getSession
hsc_env' <- liftIO $ rttiEnvironment hsc_env
setSession hsc_env'
return $ filter (not . isDerivedOccName . nameOccName)
-- For this filter, see Note [What to show to users]
$ map getName tyThings
{- Note [What to show to users]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
We don't want to display internally-generated bindings to users.
Things like the coercion axiom for newtypes. These bindings all get
OccNames that users can't write, to avoid the possiblity of name
clashes (in linker symbols). That gives a convenient way to suppress
them. The relevant predicate is OccName.isDerivedOccName.
See Trac #11051 for more background and examples.
-}
withVirtualCWD :: GhcMonad m => m a -> m a
withVirtualCWD m = do
hsc_env <- getSession
-- a virtual CWD is only necessary when we're running interpreted code in
-- the same process as the compiler.
if gopt Opt_ExternalInterpreter (hsc_dflags hsc_env) then m else do
let ic = hsc_IC hsc_env
let set_cwd = do
dir <- liftIO $ getCurrentDirectory
case ic_cwd ic of
Just dir -> liftIO $ setCurrentDirectory dir
Nothing -> return ()
return dir
reset_cwd orig_dir = do
virt_dir <- liftIO $ getCurrentDirectory
hsc_env <- getSession
let old_IC = hsc_IC hsc_env
setSession hsc_env{ hsc_IC = old_IC{ ic_cwd = Just virt_dir } }
liftIO $ setCurrentDirectory orig_dir
gbracket set_cwd reset_cwd $ \_ -> m
parseImportDecl :: GhcMonad m => String -> m (ImportDecl GhcPs)
parseImportDecl expr = withSession $ \hsc_env -> liftIO $ hscImport hsc_env expr
emptyHistory :: Int -> BoundedList History
emptyHistory size = nilBL size
handleRunStatus :: GhcMonad m
=> SingleStep -> String-> ([TyThing],GlobalRdrEnv) -> [Id]
-> EvalStatus_ [ForeignHValue] [HValueRef]
-> BoundedList History
-> m ExecResult
handleRunStatus step expr bindings final_ids status history
| RunAndLogSteps <- step = tracing
| otherwise = not_tracing
where
tracing
| EvalBreak is_exception apStack_ref ix mod_uniq resume_ctxt _ccs <- status
, not is_exception
= do
hsc_env <- getSession
let hmi = expectJust "handleRunStatus" $
lookupHptDirectly (hsc_HPT hsc_env)
(mkUniqueGrimily mod_uniq)
modl = mi_module (hm_iface hmi)
breaks = getModBreaks hmi
b <- liftIO $
breakpointStatus hsc_env (modBreaks_flags breaks) ix
if b
then not_tracing
-- This breakpoint is explicitly enabled; we want to stop
-- instead of just logging it.
else do
apStack_fhv <- liftIO $ mkFinalizedHValue hsc_env apStack_ref
let bi = BreakInfo modl ix
!history' = mkHistory hsc_env apStack_fhv bi `consBL` history
-- history is strict, otherwise our BoundedList is pointless.
fhv <- liftIO $ mkFinalizedHValue hsc_env resume_ctxt
status <- liftIO $ GHCi.resumeStmt hsc_env True fhv
handleRunStatus RunAndLogSteps expr bindings final_ids
status history'
| otherwise
= not_tracing
not_tracing
-- Hit a breakpoint
| EvalBreak is_exception apStack_ref ix mod_uniq resume_ctxt ccs <- status
= do
hsc_env <- getSession
resume_ctxt_fhv <- liftIO $ mkFinalizedHValue hsc_env resume_ctxt
apStack_fhv <- liftIO $ mkFinalizedHValue hsc_env apStack_ref
let hmi = expectJust "handleRunStatus" $
lookupHptDirectly (hsc_HPT hsc_env)
(mkUniqueGrimily mod_uniq)
modl = mi_module (hm_iface hmi)
bp | is_exception = Nothing
| otherwise = Just (BreakInfo modl ix)
(hsc_env1, names, span, decl) <- liftIO $
bindLocalsAtBreakpoint hsc_env apStack_fhv bp
let
resume = Resume
{ resumeStmt = expr, resumeContext = resume_ctxt_fhv
, resumeBindings = bindings, resumeFinalIds = final_ids
, resumeApStack = apStack_fhv
, resumeBreakInfo = bp
, resumeSpan = span, resumeHistory = toListBL history
, resumeDecl = decl
, resumeCCS = ccs
, resumeHistoryIx = 0 }
hsc_env2 = pushResume hsc_env1 resume
setSession hsc_env2
return (ExecBreak names bp)
-- Completed successfully
| EvalComplete allocs (EvalSuccess hvals) <- status
= do hsc_env <- getSession
let final_ic = extendInteractiveContextWithIds (hsc_IC hsc_env) final_ids
final_names = map getName final_ids
liftIO $ Linker.extendLinkEnv (zip final_names hvals)
hsc_env' <- liftIO $ rttiEnvironment hsc_env{hsc_IC=final_ic}
setSession hsc_env'
return (ExecComplete (Right final_names) allocs)
-- Completed with an exception
| EvalComplete alloc (EvalException e) <- status
= return (ExecComplete (Left (fromSerializableException e)) alloc)
| otherwise
= panic "not_tracing" -- actually exhaustive, but GHC can't tell
resumeExec :: GhcMonad m => (SrcSpan->Bool) -> SingleStep -> m ExecResult
resumeExec canLogSpan step
= do
hsc_env <- getSession
let ic = hsc_IC hsc_env
resume = ic_resume ic
case resume of
[] -> liftIO $
throwGhcExceptionIO (ProgramError "not stopped at a breakpoint")
(r:rs) -> do
-- unbind the temporary locals by restoring the TypeEnv from
-- before the breakpoint, and drop this Resume from the
-- InteractiveContext.
let (resume_tmp_te,resume_rdr_env) = resumeBindings r
ic' = ic { ic_tythings = resume_tmp_te,
ic_rn_gbl_env = resume_rdr_env,
ic_resume = rs }
setSession hsc_env{ hsc_IC = ic' }
-- remove any bindings created since the breakpoint from the
-- linker's environment
let old_names = map getName resume_tmp_te
new_names = [ n | thing <- ic_tythings ic
, let n = getName thing
, not (n `elem` old_names) ]
liftIO $ Linker.deleteFromLinkEnv new_names
case r of
Resume { resumeStmt = expr, resumeContext = fhv
, resumeBindings = bindings, resumeFinalIds = final_ids
, resumeApStack = apStack, resumeBreakInfo = mb_brkpt
, resumeSpan = span
, resumeHistory = hist } -> do
withVirtualCWD $ do
status <- liftIO $ GHCi.resumeStmt hsc_env (isStep step) fhv
let prevHistoryLst = fromListBL 50 hist
hist' = case mb_brkpt of
Nothing -> prevHistoryLst
Just bi
| not $canLogSpan span -> prevHistoryLst
| otherwise -> mkHistory hsc_env apStack bi `consBL`
fromListBL 50 hist
handleRunStatus step expr bindings final_ids status hist'
back :: GhcMonad m => Int -> m ([Name], Int, SrcSpan, String)
back n = moveHist (+n)
forward :: GhcMonad m => Int -> m ([Name], Int, SrcSpan, String)
forward n = moveHist (subtract n)
moveHist :: GhcMonad m => (Int -> Int) -> m ([Name], Int, SrcSpan, String)
moveHist fn = do
hsc_env <- getSession
case ic_resume (hsc_IC hsc_env) of
[] -> liftIO $
throwGhcExceptionIO (ProgramError "not stopped at a breakpoint")
(r:rs) -> do
let ix = resumeHistoryIx r
history = resumeHistory r
new_ix = fn ix
--
when (history `lengthLessThan` new_ix) $ liftIO $
throwGhcExceptionIO (ProgramError "no more logged breakpoints")
when (new_ix < 0) $ liftIO $
throwGhcExceptionIO (ProgramError "already at the beginning of the history")
let
update_ic apStack mb_info = do
(hsc_env1, names, span, decl) <-
liftIO $ bindLocalsAtBreakpoint hsc_env apStack mb_info
let ic = hsc_IC hsc_env1
r' = r { resumeHistoryIx = new_ix }
ic' = ic { ic_resume = r':rs }
setSession hsc_env1{ hsc_IC = ic' }
return (names, new_ix, span, decl)
-- careful: we want apStack to be the AP_STACK itself, not a thunk
-- around it, hence the cases are carefully constructed below to
-- make this the case. ToDo: this is v. fragile, do something better.
if new_ix == 0
then case r of
Resume { resumeApStack = apStack,
resumeBreakInfo = mb_brkpt } ->
update_ic apStack mb_brkpt
else case history !! (new_ix - 1) of
History{..} ->
update_ic historyApStack (Just historyBreakInfo)
-- -----------------------------------------------------------------------------
-- After stopping at a breakpoint, add free variables to the environment
result_fs :: FastString
result_fs = fsLit "_result"
bindLocalsAtBreakpoint
:: HscEnv
-> ForeignHValue
-> Maybe BreakInfo
-> IO (HscEnv, [Name], SrcSpan, String)
-- Nothing case: we stopped when an exception was raised, not at a
-- breakpoint. We have no location information or local variables to
-- bind, all we can do is bind a local variable to the exception
-- value.
bindLocalsAtBreakpoint hsc_env apStack Nothing = do
let exn_occ = mkVarOccFS (fsLit "_exception")
span = mkGeneralSrcSpan (fsLit "<unknown>")
exn_name <- newInteractiveBinder hsc_env exn_occ span
let e_fs = fsLit "e"
e_name = mkInternalName (getUnique e_fs) (mkTyVarOccFS e_fs) span
e_tyvar = mkRuntimeUnkTyVar e_name liftedTypeKind
exn_id = Id.mkVanillaGlobal exn_name (mkTyVarTy e_tyvar)
ictxt0 = hsc_IC hsc_env
ictxt1 = extendInteractiveContextWithIds ictxt0 [exn_id]
--
Linker.extendLinkEnv [(exn_name, apStack)]
return (hsc_env{ hsc_IC = ictxt1 }, [exn_name], span, "<exception thrown>")
-- Just case: we stopped at a breakpoint, we have information about the location
-- of the breakpoint and the free variables of the expression.
bindLocalsAtBreakpoint hsc_env apStack_fhv (Just BreakInfo{..}) = do
let
hmi = expectJust "bindLocalsAtBreakpoint" $
lookupHpt (hsc_HPT hsc_env) (moduleName breakInfo_module)
breaks = getModBreaks hmi
info = expectJust "bindLocalsAtBreakpoint2" $
IntMap.lookup breakInfo_number (modBreaks_breakInfo breaks)
vars = cgb_vars info
result_ty = cgb_resty info
occs = modBreaks_vars breaks ! breakInfo_number
span = modBreaks_locs breaks ! breakInfo_number
decl = intercalate "." $ modBreaks_decls breaks ! breakInfo_number
-- Filter out any unboxed ids;
-- we can't bind these at the prompt
pointers = filter (\(id,_) -> isPointer id) vars
isPointer id | [rep] <- typePrimRep (idType id)
, isGcPtrRep rep = True
| otherwise = False
(ids, offsets) = unzip pointers
free_tvs = tyCoVarsOfTypesList (result_ty:map idType ids)
-- It might be that getIdValFromApStack fails, because the AP_STACK
-- has been accidentally evaluated, or something else has gone wrong.
-- So that we don't fall over in a heap when this happens, just don't
-- bind any free variables instead, and we emit a warning.
mb_hValues <-
mapM (getBreakpointVar hsc_env apStack_fhv . fromIntegral) offsets
when (any isNothing mb_hValues) $
debugTraceMsg (hsc_dflags hsc_env) 1 $
text "Warning: _result has been evaluated, some bindings have been lost"
us <- mkSplitUniqSupply 'I' -- Dodgy; will give the same uniques every time
let tv_subst = newTyVars us free_tvs
filtered_ids = [ id | (id, Just _hv) <- zip ids mb_hValues ]
(_,tidy_tys) = tidyOpenTypes emptyTidyEnv $
map (substTy tv_subst . idType) filtered_ids
new_ids <- zipWith3M mkNewId occs tidy_tys filtered_ids
result_name <- newInteractiveBinder hsc_env (mkVarOccFS result_fs) span
let result_id = Id.mkVanillaGlobal result_name
(substTy tv_subst result_ty)
result_ok = isPointer result_id
final_ids | result_ok = result_id : new_ids
| otherwise = new_ids
ictxt0 = hsc_IC hsc_env
ictxt1 = extendInteractiveContextWithIds ictxt0 final_ids
names = map idName new_ids
let fhvs = catMaybes mb_hValues
Linker.extendLinkEnv (zip names fhvs)
when result_ok $ Linker.extendLinkEnv [(result_name, apStack_fhv)]
hsc_env1 <- rttiEnvironment hsc_env{ hsc_IC = ictxt1 }
return (hsc_env1, if result_ok then result_name:names else names, span, decl)
where
-- We need a fresh Unique for each Id we bind, because the linker
-- state is single-threaded and otherwise we'd spam old bindings
-- whenever we stop at a breakpoint. The InteractveContext is properly
-- saved/restored, but not the linker state. See #1743, test break026.
mkNewId :: OccName -> Type -> Id -> IO Id
mkNewId occ ty old_id
= do { name <- newInteractiveBinder hsc_env occ (getSrcSpan old_id)
; return (Id.mkVanillaGlobalWithInfo name ty (idInfo old_id)) }
newTyVars :: UniqSupply -> [TcTyVar] -> TCvSubst
-- Similarly, clone the type variables mentioned in the types
-- we have here, *and* make them all RuntimeUnk tyvars
newTyVars us tvs
= mkTvSubstPrs [ (tv, mkTyVarTy (mkRuntimeUnkTyVar name (tyVarKind tv)))
| (tv, uniq) <- tvs `zip` uniqsFromSupply us
, let name = setNameUnique (tyVarName tv) uniq ]
rttiEnvironment :: HscEnv -> IO HscEnv
rttiEnvironment hsc_env@HscEnv{hsc_IC=ic} = do
let tmp_ids = [id | AnId id <- ic_tythings ic]
incompletelyTypedIds =
[id | id <- tmp_ids
, not $ noSkolems id
, (occNameFS.nameOccName.idName) id /= result_fs]
hsc_env' <- foldM improveTypes hsc_env (map idName incompletelyTypedIds)
return hsc_env'
where
noSkolems = noFreeVarsOfType . idType
improveTypes hsc_env@HscEnv{hsc_IC=ic} name = do
let tmp_ids = [id | AnId id <- ic_tythings ic]
Just id = find (\i -> idName i == name) tmp_ids
if noSkolems id
then return hsc_env
else do
mb_new_ty <- reconstructType hsc_env 10 id
let old_ty = idType id
case mb_new_ty of
Nothing -> return hsc_env
Just new_ty -> do
case improveRTTIType hsc_env old_ty new_ty of
Nothing -> return $
WARN(True, text (":print failed to calculate the "
++ "improvement for a type")) hsc_env
Just subst -> do
let dflags = hsc_dflags hsc_env
when (dopt Opt_D_dump_rtti dflags) $
printInfoForUser dflags alwaysQualify $
fsep [text "RTTI Improvement for", ppr id, equals, ppr subst]
let ic' = substInteractiveContext ic subst
return hsc_env{hsc_IC=ic'}
pushResume :: HscEnv -> Resume -> HscEnv
pushResume hsc_env resume = hsc_env { hsc_IC = ictxt1 }
where
ictxt0 = hsc_IC hsc_env
ictxt1 = ictxt0 { ic_resume = resume : ic_resume ictxt0 }
-- -----------------------------------------------------------------------------
-- Abandoning a resume context
abandon :: GhcMonad m => m Bool
abandon = do
hsc_env <- getSession
let ic = hsc_IC hsc_env
resume = ic_resume ic
case resume of
[] -> return False
r:rs -> do
setSession hsc_env{ hsc_IC = ic { ic_resume = rs } }
liftIO $ abandonStmt hsc_env (resumeContext r)
return True
abandonAll :: GhcMonad m => m Bool
abandonAll = do
hsc_env <- getSession
let ic = hsc_IC hsc_env
resume = ic_resume ic
case resume of
[] -> return False
rs -> do
setSession hsc_env{ hsc_IC = ic { ic_resume = [] } }
liftIO $ mapM_ (abandonStmt hsc_env. resumeContext) rs
return True
-- -----------------------------------------------------------------------------
-- Bounded list, optimised for repeated cons
data BoundedList a = BL
{-# UNPACK #-} !Int -- length
{-# UNPACK #-} !Int -- bound
[a] -- left
[a] -- right, list is (left ++ reverse right)
nilBL :: Int -> BoundedList a
nilBL bound = BL 0 bound [] []
consBL :: a -> BoundedList a -> BoundedList a
consBL a (BL len bound left right)
| len < bound = BL (len+1) bound (a:left) right
| null right = BL len bound [a] $! tail (reverse left)
| otherwise = BL len bound (a:left) $! tail right
toListBL :: BoundedList a -> [a]
toListBL (BL _ _ left right) = left ++ reverse right
fromListBL :: Int -> [a] -> BoundedList a
fromListBL bound l = BL (length l) bound l []
-- lenBL (BL len _ _ _) = len
-- -----------------------------------------------------------------------------
-- | Set the interactive evaluation context.
--
-- (setContext imports) sets the ic_imports field (which in turn
-- determines what is in scope at the prompt) to 'imports', and
-- constructs the ic_rn_glb_env environment to reflect it.
--
-- We retain in scope all the things defined at the prompt, and kept
-- in ic_tythings. (Indeed, they shadow stuff from ic_imports.)
setContext :: GhcMonad m => [InteractiveImport] -> m ()
setContext imports
= do { hsc_env <- getSession
; let dflags = hsc_dflags hsc_env
; all_env_err <- liftIO $ findGlobalRdrEnv hsc_env imports
; case all_env_err of
Left (mod, err) ->
liftIO $ throwGhcExceptionIO (formatError dflags mod err)
Right all_env -> do {
; let old_ic = hsc_IC hsc_env
!final_rdr_env = all_env `icExtendGblRdrEnv` ic_tythings old_ic
; setSession
hsc_env{ hsc_IC = old_ic { ic_imports = imports
, ic_rn_gbl_env = final_rdr_env }}}}
where
formatError dflags mod err = ProgramError . showSDoc dflags $
text "Cannot add module" <+> ppr mod <+>
text "to context:" <+> text err
findGlobalRdrEnv :: HscEnv -> [InteractiveImport]
-> IO (Either (ModuleName, String) GlobalRdrEnv)
-- Compute the GlobalRdrEnv for the interactive context
findGlobalRdrEnv hsc_env imports
= do { idecls_env <- hscRnImportDecls hsc_env idecls
-- This call also loads any orphan modules
; return $ case partitionEithers (map mkEnv imods) of
([], imods_env) -> Right (foldr plusGlobalRdrEnv idecls_env imods_env)
(err : _, _) -> Left err }
where
idecls :: [LImportDecl GhcPs]
idecls = [noLoc d | IIDecl d <- imports]
imods :: [ModuleName]
imods = [m | IIModule m <- imports]
mkEnv mod = case mkTopLevEnv (hsc_HPT hsc_env) mod of
Left err -> Left (mod, err)
Right env -> Right env
availsToGlobalRdrEnv :: ModuleName -> [AvailInfo] -> GlobalRdrEnv
availsToGlobalRdrEnv mod_name avails
= mkGlobalRdrEnv (gresFromAvails (Just imp_spec) avails)
where
-- We're building a GlobalRdrEnv as if the user imported
-- all the specified modules into the global interactive module
imp_spec = ImpSpec { is_decl = decl, is_item = ImpAll}
decl = ImpDeclSpec { is_mod = mod_name, is_as = mod_name,
is_qual = False,
is_dloc = srcLocSpan interactiveSrcLoc }
mkTopLevEnv :: HomePackageTable -> ModuleName -> Either String GlobalRdrEnv
mkTopLevEnv hpt modl
= case lookupHpt hpt modl of
Nothing -> Left "not a home module"
Just details ->
case mi_globals (hm_iface details) of
Nothing -> Left "not interpreted"
Just env -> Right env
-- | Get the interactive evaluation context, consisting of a pair of the
-- set of modules from which we take the full top-level scope, and the set
-- of modules from which we take just the exports respectively.
getContext :: GhcMonad m => m [InteractiveImport]
getContext = withSession $ \HscEnv{ hsc_IC=ic } ->
return (ic_imports ic)
-- | Returns @True@ if the specified module is interpreted, and hence has
-- its full top-level scope available.
moduleIsInterpreted :: GhcMonad m => Module -> m Bool
moduleIsInterpreted modl = withSession $ \h ->
if moduleUnitId modl /= thisPackage (hsc_dflags h)
then return False
else case lookupHpt (hsc_HPT h) (moduleName modl) of
Just details -> return (isJust (mi_globals (hm_iface details)))
_not_a_home_module -> return False
-- | Looks up an identifier in the current interactive context (for :info)
-- Filter the instances by the ones whose tycons (or clases resp)
-- are in scope (qualified or otherwise). Otherwise we list a whole lot too many!
-- The exact choice of which ones to show, and which to hide, is a judgement call.
-- (see Trac #1581)
getInfo :: GhcMonad m => Bool -> Name
-> m (Maybe (TyThing,Fixity,[ClsInst],[FamInst], SDoc))
getInfo allInfo name
= withSession $ \hsc_env ->
do mb_stuff <- liftIO $ hscTcRnGetInfo hsc_env name
case mb_stuff of
Nothing -> return Nothing
Just (thing, fixity, cls_insts, fam_insts, docs) -> do
let rdr_env = ic_rn_gbl_env (hsc_IC hsc_env)
-- Filter the instances based on whether the constituent names of their
-- instance heads are all in scope.
let cls_insts' = filter (plausible rdr_env . orphNamesOfClsInst) cls_insts
fam_insts' = filter (plausible rdr_env . orphNamesOfFamInst) fam_insts
return (Just (thing, fixity, cls_insts', fam_insts', docs))
where
plausible rdr_env names
-- Dfun involving only names that are in ic_rn_glb_env
= allInfo
|| nameSetAll ok names
where -- A name is ok if it's in the rdr_env,
-- whether qualified or not
ok n | n == name = True
-- The one we looked for in the first place!
| pretendNameIsInScope n = True
| isBuiltInSyntax n = True
| isCTupleTyConName n = True
| isExternalName n = isJust (lookupGRE_Name rdr_env n)
| otherwise = True
-- | Returns all names in scope in the current interactive context
getNamesInScope :: GhcMonad m => m [Name]
getNamesInScope = withSession $ \hsc_env -> do
return (map gre_name (globalRdrEnvElts (ic_rn_gbl_env (hsc_IC hsc_env))))
-- | Returns all 'RdrName's in scope in the current interactive
-- context, excluding any that are internally-generated.
getRdrNamesInScope :: GhcMonad m => m [RdrName]
getRdrNamesInScope = withSession $ \hsc_env -> do
let
ic = hsc_IC hsc_env
gbl_rdrenv = ic_rn_gbl_env ic
gbl_names = concatMap greRdrNames $ globalRdrEnvElts gbl_rdrenv
-- Exclude internally generated names; see e.g. Trac #11328
return (filter (not . isDerivedOccName . rdrNameOcc) gbl_names)
-- | Parses a string as an identifier, and returns the list of 'Name's that
-- the identifier can refer to in the current interactive context.
parseName :: GhcMonad m => String -> m [Name]
parseName str = withSession $ \hsc_env -> liftIO $
do { lrdr_name <- hscParseIdentifier hsc_env str
; hscTcRnLookupRdrName hsc_env lrdr_name }
-- | Returns @True@ if passed string is a statement.
isStmt :: DynFlags -> String -> Bool
isStmt dflags stmt =
case parseThing Parser.parseStmt dflags stmt of
Lexer.POk _ _ -> True
Lexer.PFailed _ _ _ -> False
-- | Returns @True@ if passed string has an import declaration.
hasImport :: DynFlags -> String -> Bool
hasImport dflags stmt =
case parseThing Parser.parseModule dflags stmt of
Lexer.POk _ thing -> hasImports thing
Lexer.PFailed _ _ _ -> False
where
hasImports = not . null . hsmodImports . unLoc
-- | Returns @True@ if passed string is an import declaration.
isImport :: DynFlags -> String -> Bool
isImport dflags stmt =
case parseThing Parser.parseImport dflags stmt of
Lexer.POk _ _ -> True
Lexer.PFailed _ _ _ -> False
-- | Returns @True@ if passed string is a declaration but __/not a splice/__.
isDecl :: DynFlags -> String -> Bool
isDecl dflags stmt = do
case parseThing Parser.parseDeclaration dflags stmt of
Lexer.POk _ thing ->
case unLoc thing of
SpliceD _ _ -> False
_ -> True
Lexer.PFailed _ _ _ -> False
parseThing :: Lexer.P thing -> DynFlags -> String -> Lexer.ParseResult thing
parseThing parser dflags stmt = do
let buf = stringToStringBuffer stmt
loc = mkRealSrcLoc (fsLit "<interactive>") 1 1
Lexer.unP parser (Lexer.mkPState dflags buf loc)
getDocs :: GhcMonad m
=> Name
-> m (Either GetDocsFailure (Maybe HsDocString, Map Int HsDocString))
-- TODO: What about docs for constructors etc.?
getDocs name =
withSession $ \hsc_env -> do
case nameModule_maybe name of
Nothing -> pure (Left (NameHasNoModule name))
Just mod -> do
if isInteractiveModule mod
then pure (Left InteractiveName)
else do
ModIface { mi_doc_hdr = mb_doc_hdr
, mi_decl_docs = DeclDocMap dmap
, mi_arg_docs = ArgDocMap amap
} <- liftIO $ hscGetModuleInterface hsc_env mod
if isNothing mb_doc_hdr && Map.null dmap && Map.null amap
then pure (Left (NoDocsInIface mod compiled))
else pure (Right ( Map.lookup name dmap
, Map.findWithDefault Map.empty name amap))
where
compiled =
-- TODO: Find a more direct indicator.
case nameSrcLoc name of
RealSrcLoc {} -> False
UnhelpfulLoc {} -> True
-- | Failure modes for 'getDocs'.
-- TODO: Find a way to differentiate between modules loaded without '-haddock'
-- and modules that contain no docs.
data GetDocsFailure
-- | 'nameModule_maybe' returned 'Nothing'.
= NameHasNoModule Name
-- | This is probably because the module was loaded without @-haddock@,
-- but it's also possible that the entire module contains no documentation.
| NoDocsInIface
Module
Bool -- ^ 'True': The module was compiled.
-- 'False': The module was :loaded.
-- | The 'Name' was defined interactively.
| InteractiveName
instance Outputable GetDocsFailure where
ppr (NameHasNoModule name) =
quotes (ppr name) <+> text "has no module where we could look for docs."
ppr (NoDocsInIface mod compiled) = vcat
[ text "Can't find any documentation for" <+> ppr mod <> char '.'
, text "This is probably because the module was"
<+> text (if compiled then "compiled" else "loaded")
<+> text "without '-haddock',"
, text "but it's also possible that the module contains no documentation."
, text ""
, if compiled
then text "Try re-compiling with '-haddock'."
else text "Try running ':set -haddock' and :load the file again."
-- TODO: Figure out why :reload doesn't load the docs and maybe fix it.
]
ppr InteractiveName =
text "Docs are unavailable for interactive declarations."
-- -----------------------------------------------------------------------------
-- Getting the type of an expression
-- | Get the type of an expression
-- Returns the type as described by 'TcRnExprMode'
exprType :: GhcMonad m => TcRnExprMode -> String -> m Type
exprType mode expr = withSession $ \hsc_env -> do
ty <- liftIO $ hscTcExpr hsc_env mode expr
return $ tidyType emptyTidyEnv ty
-- -----------------------------------------------------------------------------
-- Getting the kind of a type
-- | Get the kind of a type
typeKind :: GhcMonad m => Bool -> String -> m (Type, Kind)
typeKind normalise str = withSession $ \hsc_env -> do
liftIO $ hscKcType hsc_env normalise str
-----------------------------------------------------------------------------
-- Compile an expression, run it, and deliver the result
-- | Parse an expression, the parsed expression can be further processed and
-- passed to compileParsedExpr.
parseExpr :: GhcMonad m => String -> m (LHsExpr GhcPs)
parseExpr expr = withSession $ \hsc_env -> do
liftIO $ runInteractiveHsc hsc_env $ hscParseExpr expr
-- | Compile an expression, run it, and deliver the resulting HValue.
compileExpr :: GhcMonad m => String -> m HValue
compileExpr expr = do
parsed_expr <- parseExpr expr
compileParsedExpr parsed_expr
-- | Compile an expression, run it, and deliver the resulting HValue.
compileExprRemote :: GhcMonad m => String -> m ForeignHValue
compileExprRemote expr = do
parsed_expr <- parseExpr expr
compileParsedExprRemote parsed_expr
-- | Compile a parsed expression (before renaming), run it, and deliver
-- the resulting HValue.
compileParsedExprRemote :: GhcMonad m => LHsExpr GhcPs -> m ForeignHValue
compileParsedExprRemote expr@(L loc _) = withSession $ \hsc_env -> do
-- > let _compileParsedExpr = expr
-- Create let stmt from expr to make hscParsedStmt happy.
-- We will ignore the returned [Id], namely [expr_id], and not really
-- create a new binding.
let expr_fs = fsLit "_compileParsedExpr"
expr_name = mkInternalName (getUnique expr_fs) (mkTyVarOccFS expr_fs) loc
let_stmt = L loc . LetStmt noExt . L loc . (HsValBinds noExt) $
ValBinds noExt
(unitBag $ mkHsVarBind loc (getRdrName expr_name) expr) []
pstmt <- liftIO $ hscParsedStmt hsc_env let_stmt
let (hvals_io, fix_env) = case pstmt of
Just ([_id], hvals_io', fix_env') -> (hvals_io', fix_env')
_ -> panic "compileParsedExprRemote"
updateFixityEnv fix_env
status <- liftIO $ evalStmt hsc_env False (EvalThis hvals_io)
case status of
EvalComplete _ (EvalSuccess [hval]) -> return hval
EvalComplete _ (EvalException e) ->
liftIO $ throwIO (fromSerializableException e)
_ -> panic "compileParsedExpr"
compileParsedExpr :: GhcMonad m => LHsExpr GhcPs -> m HValue
compileParsedExpr expr = do
fhv <- compileParsedExprRemote expr
dflags <- getDynFlags
liftIO $ wormhole dflags fhv
-- | Compile an expression, run it and return the result as a Dynamic.
dynCompileExpr :: GhcMonad m => String -> m Dynamic
dynCompileExpr expr = do
parsed_expr <- parseExpr expr
-- > Data.Dynamic.toDyn expr
let loc = getLoc parsed_expr
to_dyn_expr = mkHsApp (L loc . HsVar noExt . L loc $ getRdrName toDynName)
parsed_expr
hval <- compileParsedExpr to_dyn_expr
return (unsafeCoerce# hval :: Dynamic)
-----------------------------------------------------------------------------
-- show a module and it's source/object filenames
showModule :: GhcMonad m => ModSummary -> m String
showModule mod_summary =
withSession $ \hsc_env -> do
interpreted <- moduleIsBootOrNotObjectLinkable mod_summary
let dflags = hsc_dflags hsc_env
return (showModMsg dflags (hscTarget dflags) interpreted mod_summary)
moduleIsBootOrNotObjectLinkable :: GhcMonad m => ModSummary -> m Bool
moduleIsBootOrNotObjectLinkable mod_summary = withSession $ \hsc_env ->
case lookupHpt (hsc_HPT hsc_env) (ms_mod_name mod_summary) of
Nothing -> panic "missing linkable"
Just mod_info -> return $ case hm_linkable mod_info of
Nothing -> True
Just linkable -> not (isObjectLinkable linkable)
----------------------------------------------------------------------------
-- RTTI primitives
obtainTermFromVal :: HscEnv -> Int -> Bool -> Type -> a -> IO Term
obtainTermFromVal hsc_env bound force ty x =
cvObtainTerm hsc_env bound force ty (unsafeCoerce# x)
obtainTermFromId :: HscEnv -> Int -> Bool -> Id -> IO Term
obtainTermFromId hsc_env bound force id = do
let dflags = hsc_dflags hsc_env
hv <- Linker.getHValue hsc_env (varName id) >>= wormhole dflags
cvObtainTerm hsc_env bound force (idType id) hv
-- Uses RTTI to reconstruct the type of an Id, making it less polymorphic
reconstructType :: HscEnv -> Int -> Id -> IO (Maybe Type)
reconstructType hsc_env bound id = do
let dflags = hsc_dflags hsc_env
hv <- Linker.getHValue hsc_env (varName id) >>= wormhole dflags
cvReconstructType hsc_env bound (idType id) hv
mkRuntimeUnkTyVar :: Name -> Kind -> TyVar
mkRuntimeUnkTyVar name kind = mkTcTyVar name kind RuntimeUnk