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| author | Krzysztof Gogolewski <krzysztof.gogolewski@tweag.io> | 2022-12-05 18:58:34 +0100 |
|---|---|---|
| committer | Marge Bot <ben+marge-bot@smart-cactus.org> | 2022-12-08 08:33:36 -0500 |
| commit | 7658cdd47198512b699492688f51fc8682d194cd (patch) | |
| tree | 90712444d737b5d892578619f4c2db485c9bc411 /libraries | |
| parent | 9ec76f61c880539114314fc3e4f96a4694f38ebe (diff) | |
| download | haskell-7658cdd47198512b699492688f51fc8682d194cd.tar.gz | |
Restore show (typeRep @[]) == "[]"
The Show instance for TypeRep [] has changed in 9.5 to output "List"
because the name of the type constructor changed.
This seems to be accidental and is inconsistent with TypeReps of saturated
lists, which are printed as e.g. "[Int]".
For now, I'm restoring the old behavior; in the future,
maybe we should show TypeReps without puns (List, Tuple, Type).
Diffstat (limited to 'libraries')
| -rw-r--r-- | libraries/base/Data/Typeable/Internal.hs | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/libraries/base/Data/Typeable/Internal.hs b/libraries/base/Data/Typeable/Internal.hs index 209324d585..51ee0f745e 100644 --- a/libraries/base/Data/Typeable/Internal.hs +++ b/libraries/base/Data/Typeable/Internal.hs @@ -836,6 +836,8 @@ instance Show (TypeRep (a :: k)) where showTypeable :: Int -> TypeRep (a :: k) -> ShowS showTypeable _ TrType = showChar '*' showTypeable _ rep + | isListTyCon tc, [] <- tys = + showString "[]" | isListTyCon tc, [ty] <- tys = showChar '[' . shows ty . showChar ']' |