Cabal/src/Distribution/Types/AnnotatedId.hs

   1 {-# LANGUAGE DeriveFunctor #-}
   2
   3 module Distribution.Types.AnnotatedId
   4   ( AnnotatedId (..)
   5   ) where
   6
   7 import Distribution.Compat.Prelude
   8 import Prelude ()
   9
  10 import Distribution.Package
  11 import Distribution.Types.ComponentName
  12
  13 -- | An 'AnnotatedId' is a 'ComponentId', 'UnitId', etc.
  14 -- which is annotated with some other useful information
  15 -- that is useful for printing to users, etc.
  16 --
  17 -- Invariant: if ann_id x == ann_id y, then ann_pid x == ann_pid y
  18 -- and ann_cname x == ann_cname y
  19 data AnnotatedId id = AnnotatedId
  20   { ann_pid :: PackageId
  21   , ann_cname :: ComponentName
  22   , ann_id :: id
  23   }
  24   deriving (Show, Functor)
  25
  26 instance Eq id => Eq (AnnotatedId id) where
  27   x == y = ann_id x == ann_id y
  28
  29 instance Ord id => Ord (AnnotatedId id) where
  30   compare x y = compare (ann_id x) (ann_id y)
  31
  32 instance Package (AnnotatedId id) where
  33   packageId = ann_pid