diff options
Diffstat (limited to 'compiler/GHC')
| -rw-r--r-- | compiler/GHC/HsToCore/Expr.hs | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/compiler/GHC/HsToCore/Expr.hs b/compiler/GHC/HsToCore/Expr.hs index c9868cc381..24b4a76892 100644 --- a/compiler/GHC/HsToCore/Expr.hs +++ b/compiler/GHC/HsToCore/Expr.hs @@ -70,6 +70,8 @@ import GHC.Utils.Panic import GHC.Core.PatSyn import Control.Monad +import qualified GHC.LanguageExtensions as LangExt + {- ************************************************************************ * * @@ -347,7 +349,11 @@ converting to core it must become a CO. Note [Desugaring operator sections] ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -At first it looks as if we can convert +Desugaring left sections with -XPostfixOperators is straightforward: convert +(expr `op`) to (op expr). + +Without -XPostfixOperators it's a bit more tricky. At first it looks as if we +can convert (expr `op`) @@ -398,6 +404,13 @@ dsExpr e@(OpApp _ e1 op e2) -- See Note [Desugaring operator sections]. -- N.B. this also must handle postfix operator sections due to -XPostfixOperators. dsExpr e@(SectionL _ expr op) = do + postfix_operators <- xoptM LangExt.PostfixOperators + if postfix_operators then + -- Desugar (e !) to ((!) e) + do { op' <- dsLExpr op + ; dsWhenNoErrs (dsLExprNoLP expr) $ \expr' -> + mkCoreAppDs (text "sectionl" <+> ppr expr) op' expr' } + else do core_op <- dsLExpr op x_core <- dsLExpr expr case splitFunTys (exprType core_op) of |