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This program compiles:

{-# LANGUAGE TemplateHaskell #-}
module Bug1 where

import Language.Haskell.TH

$([d| f :: Int
      f = $(varE 'id `appTypeE` conT ''Int `appE` litE (integerL 42)) |])

But it shouldn't: this splices in code that uses TypeApplications, but the language extension isn't enabled! What's worse, this is inconsistent with visible kind applications, since the following code //is// rejected:

{-# LANGUAGE PolyKinds #-}
{-# LANGUAGE TemplateHaskell #-}
module Bug2 where

import Data.Kind
import Language.Haskell.TH hiding (Type)

data P (a :: k) = MkP

$([d| type P' = $(conT ''P `appKindT` conT ''Type) |])

$ ~/Software/ghc4/inplace/bin/ghc-stage2 Bug2.hs
[1 of 1] Compiling Bug2             ( Bug2.hs, Bug2.o )

Bug2.hs:10:3: error:
    Illegal visible kind application ‘Type’
      Perhaps you intended to use TypeApplications
   |
10 | $([d| type P' = $(conT ''P `appKindT` conT ''Type) |])
   |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Let's bring the two into harmony. Patch incoming.

Trac metadata

Trac field	Value
Version	8.6.3
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Template Haskell
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