diff options
Diffstat (limited to 'compiler/GHC/Hs/Utils.hs')
| -rw-r--r-- | compiler/GHC/Hs/Utils.hs | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/compiler/GHC/Hs/Utils.hs b/compiler/GHC/Hs/Utils.hs index 195df82d8a..eb708cd295 100644 --- a/compiler/GHC/Hs/Utils.hs +++ b/compiler/GHC/Hs/Utils.hs @@ -109,7 +109,7 @@ module GHC.Hs.Utils( lStmtsImplicits, hsValBindsImplicits, lPatImplicits ) where -import GHC.Prelude +import GHC.Prelude hiding (head, init, last, tail) import GHC.Hs.Decls import GHC.Hs.Binds @@ -150,6 +150,8 @@ import Data.Either import Data.Foldable ( toList ) import Data.Function import Data.List ( partition, deleteBy ) +import Data.List.NonEmpty ( nonEmpty ) +import qualified Data.List.NonEmpty as NE {- ************************************************************************ @@ -220,8 +222,9 @@ mkLamCaseMatchGroup origin lc_variant (L l matches) mkLocatedList :: Semigroup a => [GenLocated (SrcAnn a) e2] -> LocatedAn an [GenLocated (SrcAnn a) e2] -mkLocatedList [] = noLocA [] -mkLocatedList ms = L (noAnnSrcSpan $ locA $ combineLocsA (head ms) (last ms)) ms +mkLocatedList ms = case nonEmpty ms of + Nothing -> noLocA [] + Just ms1 -> L (noAnnSrcSpan $ locA $ combineLocsA (NE.head ms1) (NE.last ms1)) ms mkHsApp :: LHsExpr (GhcPass id) -> LHsExpr (GhcPass id) -> LHsExpr (GhcPass id) mkHsApp e1 e2 = addCLocAA e1 e2 (HsApp noComments e1 e2) @@ -656,7 +659,7 @@ missingTupArg ann = Missing ann mkLHsPatTup :: [LPat GhcRn] -> LPat GhcRn mkLHsPatTup [] = noLocA $ TuplePat noExtField [] Boxed mkLHsPatTup [lpat] = lpat -mkLHsPatTup lpats = L (getLoc (head lpats)) $ TuplePat noExtField lpats Boxed +mkLHsPatTup lpats@(lpat:_) = L (getLoc lpat) $ TuplePat noExtField lpats Boxed -- | The Big equivalents for the source tuple expressions mkBigLHsVarTup :: IsSrcSpanAnn p a |