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-- When using DuplicateRecordFields with TemplateHaskell, it is not possible to
-- reify ambiguous names that are output by reifying field labels.
-- See also overloadedrecflds/should_run/overloadedrecfldsrun04.hs
{-# LANGUAGE DuplicateRecordFields, TemplateHaskell #-}
import Language.Haskell.TH
import Language.Haskell.TH.Syntax
data R = MkR { foo :: Int, bar :: Int }
data S = MkS { foo :: Int }
$(do info <- reify ''R
case info of
TyConI (DataD _ _ _ [RecC _ [(foo_n, _, _), (bar_n, _, _)]] _)
-> do { reify bar_n -- This is unambiguous
; reify foo_n -- This is ambiguous
; return []
}
_ -> error "unexpected result of reify")
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