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{-# LANGUAGE AllowAmbiguousTypes           , FunctionalDependencies           , KindSignatures           , MultiParamTypeClasses           , PolyKinds  #-}------------------------------------------------------------------------------- |-- Module      :  GHC.Records-- Copyright   :  (c) Adam Gundry 2015-2016-- License     :  see libraries/base/LICENSE---- Maintainer  :  cvs-ghc@haskell.org-- Stability   :  internal-- Portability :  non-portable (GHC extensions)---- This module defines the 'HasField' class used by the-- @OverloadedRecordFields@ extension.  See the-- <https://ghc.haskell.org/trac/ghc/wiki/Records/OverloadedRecordFields-- wiki page> for more details.-------------------------------------------------------------------------------moduleGHC.Records(HasField(..))where-- | Constraint representing the fact that the field @x@ belongs to-- the record type @r@ and has field type @a@.  This will be solved-- automatically, but manual instances may be provided as well.classHasField(x::k)ra|xr->awhere-- | Selector function to extract the field from the record.getField::r->a