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| author | Nathan Collins <nathan.collins@gmail.com> | 2019-05-21 13:44:55 -0400 |
|---|---|---|
| committer | Matthew Pickering <matthewtpickering@gmail.com> | 2019-05-29 16:29:57 +0100 |
| commit | c00ad4213db311d37c8e7a0867ad1853178636ee (patch) | |
| tree | cef925230763a2a7081a956cf0e5028dc4e93d93 | |
| parent | 2d2aa2031b9abc3bff7b5585ab4201948c8bba7d (diff) | |
| download | haskell-wip/thread-show.tar.gz | |
Improve ThreadId Show instancewip/thread-show
By making it include parens when a derived instance would. For example, this changes the (hypothetical) code `show (Just (ThreadId 3))` to produce `"Just (ThreadId 3)"` instead of the current `"Just ThreadId 3"`.
| -rw-r--r-- | libraries/base/GHC/Conc/Sync.hs | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/libraries/base/GHC/Conc/Sync.hs b/libraries/base/GHC/Conc/Sync.hs index 5c3e63a8e3..87491993f8 100644 --- a/libraries/base/GHC/Conc/Sync.hs +++ b/libraries/base/GHC/Conc/Sync.hs @@ -113,7 +113,7 @@ import GHC.IORef import GHC.MVar import GHC.Ptr import GHC.Real ( fromIntegral ) -import GHC.Show ( Show(..), showString ) +import GHC.Show ( Show(..), showParen, showString ) import GHC.Stable ( StablePtr(..) ) import GHC.Weak @@ -145,7 +145,7 @@ This misfeature will hopefully be corrected at a later date. -- | @since 4.2.0.0 instance Show ThreadId where - showsPrec d t = + showsPrec d t = showParen (d >= 11) $ showString "ThreadId " . showsPrec d (getThreadId (id2TSO t)) |