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API Annotations : ExprWithTySig processing discards annotated spans

In RdrHsSyn.checkAPat the processing for ExprWithTySig is defined as

   ExprWithTySig e t _ -> do e <- checkLPat msg e
                             -- Pattern signatures are parsed as sigtypes,
                             -- but they aren't explicit forall points.  Hence
                             -- we have to remove the implicit forall here.
                             let t' = case t of
                                        L _ (HsForAllTy Implicit _ _
                                             (L _ []) ty) -> ty
                                        other -> other
                             return (SigPatIn e (mkHsWithBndrs t'))

The t' variable ends up losing its original SrcSpan in the first case branch. This results in annotations becoming detached from the AST.

Trac metadata
Trac field Value
Version 7.10.1
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler (Parser)
Test case
Differential revisions
BlockedBy
Related
Blocking
CC mpickering
Operating system
Architecture
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