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GHCi reports too few instances

GHCi aspires to report all instances that can be written 
unqualified in the current scope; but it doesn't.


| ~% ghci
|    ___         ___ _
|   / _ \ /\  /\/ __(_)
|  / /_\// /_/ / /  | |      GHC Interactive, version 6.4, for 
Haskell 98.
| / /_\\/ __  / /___| |      http://www.haskell.org/ghc/
| \____/\/ /_/\____/|_|      Type :? for help.
| 
| Loading package base-1.0 ... linking ... done.
| 
| Prelude> :i Bool
| data Bool = False | True 	-- <wired into compiler>
| instance Eq Bool 	-- Imported from GHC.Base
| instance Ord Bool 	-- Imported from GHC.Base
| 
| Prelude> :i Bool
| data Bool = False | True 	-- <wired into compiler>
| instance Bounded Bool 	-- Imported from 
GHC.Enum
| instance Enum Bool 	-- Imported from 
GHC.Enum
| instance Eq Bool 	-- Imported from GHC.Base
| instance Ord Bool 	-- Imported from GHC.Base
| instance Read Bool 	-- Imported from GHC.Read
| instance Show Bool 	-- Imported from GHC.Show
Trac metadata
Trac field Value
Version None
Type Bug
TypeOfFailure OtherFailure
Priority low
Resolution ResolvedFixed
Component GHCi
Test case
Differential revisions
BlockedBy
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Blocking
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Operating system
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