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{-# 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
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