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Diffstat (limited to 'src')
-rw-r--r-- | src/Lib.hs | 1 |
1 files changed, 1 insertions, 0 deletions
@@ -822,6 +822,7 @@ headMay [] = Nothing headMay (x:_) = Just x data HeadException = HeadException deriving (Show) + instance E.Exception HeadException mustHead :: [a] -> IO a |