ghc-mod/Language/Haskell/GhcMod/Info.hs
Nikolay Yakimov 960a49c1ed [Type-constraints] Marginally better version
* Instead of listify, it walks the tree instead, so that constraints are only visible in relevant context.
* Uses Map instead of [(,)]
* Performs type substitutions in case of one child identifier found (relevant for constructor bindings)
2016-01-19 22:50:14 +03:00

79 lines
2.5 KiB
Haskell

module Language.Haskell.GhcMod.Info (
info
, types
) where
import Data.Function (on)
import Data.List (sortBy)
import System.FilePath
import Exception (ghandle, SomeException(..))
import GHC (GhcMonad, SrcSpan)
import Prelude
import qualified GHC as G
import qualified Language.Haskell.GhcMod.Gap as Gap
import Language.Haskell.GhcMod.Convert
import Language.Haskell.GhcMod.Doc
import Language.Haskell.GhcMod.DynFlags
import Language.Haskell.GhcMod.Gap
import Language.Haskell.GhcMod.Logging
import Language.Haskell.GhcMod.Monad
import Language.Haskell.GhcMod.SrcUtils
import Language.Haskell.GhcMod.Types
import Language.Haskell.GhcMod.Utils (mkRevRedirMapFunc)
import Language.Haskell.GhcMod.FileMapping (fileModSummaryWithMapping)
----------------------------------------------------------------
-- | Obtaining information of a target expression. (GHCi's info:)
info :: IOish m
=> FilePath -- ^ A target file.
-> Expression -- ^ A Haskell expression.
-> GhcModT m String
info file expr =
ghandle handler $
runGmlT' [Left file] deferErrors $
withInteractiveContext $ do
convert' =<< body
where
handler (SomeException ex) = do
gmLog GmException "info" $ text "" $$ nest 4 (showDoc ex)
convert' "Cannot show info"
body :: (GhcMonad m, GmState m, GmEnv m) => m String
body = do
m <- mkRevRedirMapFunc
sdoc <- Gap.infoThing m expr
st <- getStyle
dflag <- G.getSessionDynFlags
return $ showPage dflag st sdoc
----------------------------------------------------------------
-- | Obtaining type of a target expression. (GHCi's type:)
types :: IOish m
=> FilePath -- ^ A target file.
-> Int -- ^ Line number.
-> Int -- ^ Column number.
-> GhcModT m String
types file lineNo colNo =
ghandle handler $
runGmlT' [Left file] deferErrors $
withInteractiveContext $ do
crdl <- cradle
modSum <- fileModSummaryWithMapping (cradleCurrentDir crdl </> file)
srcSpanTypes <- getSrcSpanType modSum lineNo colNo
dflag <- G.getSessionDynFlags
st <- getStyle
convert' $ map (toTup dflag st) $ sortBy (cmp `on` fst) srcSpanTypes
where
handler (SomeException ex) = do
gmLog GmException "types" $ showDoc ex
return []
getSrcSpanType :: (GhcMonad m) => G.ModSummary -> Int -> Int -> m [(SrcSpan, G.Type)]
getSrcSpanType modSum lineNo colNo =
G.parseModule modSum
>>= G.typecheckModule
>>= flip collectSpansTypes (lineNo, colNo)