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Allow applying type to label

{-# LANGUAGE FlexibleInstances     #-}
{-# LANGUAGE FlexibleContexts      #-}
{-# LANGUAGE TypeApplications      #-}
{-# LANGUAGE OverloadedLabels      #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE DataKinds             #-}

import GHC.TypeLits
import GHC.OverloadedLabels

instance IsLabel "answer" Int where
  fromLabel _ = 42

answer :: IsLabel "answer" a => a
answer = #answer

The follow works:

>>> answer @Int
42

but fails with a label:

>>> #answer @Int
<interactive>:...:1: error:
     Cannot not apply expression of type t0
      to a visible type argument Int
     In the expression: #answer @Int
      In an equation for it: it = #answer @Int
Trac metadata
Trac field Value
Version 7.10.3
Type FeatureRequest
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler
Test case
Differential revisions
BlockedBy
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Blocking
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Operating system
Architecture
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