-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | Extra functions I use.
--   
--   A library of extra functions for the standard Haskell libraries. Most
--   functions are new, and add missing functionality. Some are available
--   in later versions of GHC, but this package ports them back to GHC 7.2.
@package extra
@version 0.2

module System.Environment.Extra

-- | Returns the absolute pathname of the current executable.
--   
--   Note that for scripts and interactive sessions, this is the path to
--   the interpreter (e.g. ghci.)
getExecutablePath :: IO FilePath

-- | Return the value of the environment variable <tt>var</tt>, or
--   <tt>Nothing</tt> if there is no such value.
--   
--   For POSIX users, this is equivalent to <a>getEnv</a>.
lookupEnv :: String -> IO (Maybe String)

module Numeric.Extra
showDP :: RealFloat a => Int -> a -> String
intToDouble :: Int -> Double
intToFloat :: Int -> Float
floatToDouble :: Float -> Double
doubleToFloat :: Double -> Float

module System.Time.Extra
sleep :: Double -> IO ()
subtractTime :: UTCTime -> UTCTime -> Double
showTime :: Double -> String

-- | Call once at the start, then call repeatedly to get Time values out
offsetTime :: IO (IO Double)

-- | Like offsetTime, but results will never decrease (though they may stay
--   the same)
offsetTimeIncrease :: IO (IO Double)
duration :: IO a -> IO (Double, a)

module Data.Tuple.Extra
dupe :: a -> (a, a)
fst3 :: (a, b, c) -> a
snd3 :: (a, b, c) -> b
thd3 :: (a, b, c) -> c
concat2 :: [([a], [b])] -> ([a], [b])
concat3 :: [([a], [b], [c])] -> ([a], [b], [c])


-- | This module extends <a>Data.List</a> with extra functions of a similar
--   nature. The package also exports the existing <a>Data.List</a>
--   functions. Some of the names and semantics were inspired by the
--   <tt>text</tt> package.
module Data.List.Extra
lower :: String -> String
upper :: String -> String
strip :: String -> String
stripStart :: String -> String
stripEnd :: String -> String
dropAround :: (a -> Bool) -> [a] -> [a]
word1 :: String -> (String, String)
drop1 :: [a] -> [a]
list :: b -> (a -> [a] -> b) -> [a] -> b
uncons :: [a] -> Maybe (a, [a])
unsnoc :: [a] -> Maybe ([a], a)
cons :: a -> [a] -> [a]
snoc :: [a] -> a -> [a]
groupSort :: Ord k => [(k, v)] -> [(k, [v])]
groupSortOn :: Ord a => (k -> a) -> [(k, v)] -> [(k, [v])]
nubOn :: Eq b => (a -> b) -> [a] -> [a]
groupOn :: Eq b => (a -> b) -> [a] -> [[a]]
sortOn :: Ord b => (a -> b) -> [a] -> [a]
chop :: ([a] -> (b, [a])) -> [a] -> [b]
for :: [a] -> (a -> b) -> [b]
rep :: Eq a => a -> a -> a -> a
reps :: Eq a => a -> a -> [a] -> [a]
disjoint :: Eq a => [a] -> [a] -> Bool
distinct :: Eq a => [a] -> Bool
dropEnd :: Int -> [a] -> [a]
takeEnd :: Int -> [a] -> [a]
breakEnd :: (a -> Bool) -> [a] -> ([a], [a])
spanEnd :: (a -> Bool) -> [a] -> ([a], [a])

-- | The <a>dropWhileEnd</a> function drops the largest suffix of a list in
--   which the given predicate holds for all elements. For example:
--   
--   <pre>
--   dropWhileEnd isSpace "foo\n" == "foo"
--   dropWhileEnd isSpace "foo bar" == "foo bar"
--   dropWhileEnd isSpace ("foo\n" ++ undefined) == "foo" ++ undefined
--   </pre>
dropWhileEnd :: (a -> Bool) -> [a] -> [a]
takeWhileEnd :: (a -> Bool) -> [a] -> [a]

-- | Return the prefix of the second string if its suffix matches the
--   entire first string.
--   
--   Examples:
--   
--   <pre>
--   stripSuffix "bar" "foobar" == Just "foo"
--   stripSuffix ""    "baz"    == Just "baz"
--   stripSuffix "foo" "quux"   == Nothing
--   </pre>
stripSuffix :: Eq a => [a] -> [a] -> Maybe [a]
concatUnzip :: [([a], [b])] -> ([a], [b])
merge :: Ord a => [a] -> [a] -> [a]
mergeBy :: (a -> a -> Ordering) -> [a] -> [a] -> [a]
replace :: String -> String -> String -> String
wordsBy :: (a -> Bool) -> [a] -> [[a]]
linesBy :: (a -> Bool) -> [a] -> [[a]]
firstJust :: (a -> Maybe b) -> [a] -> Maybe b

-- | Find the first instance of <tt>needle</tt> in <tt>haystack</tt>. The
--   first element of the returned tuple is the prefix of <tt>haystack</tt>
--   before <tt>needle</tt> is matched. The second is the remainder of
--   <tt>haystack</tt>, starting with the match.
--   
--   Examples:
--   
--   <pre>
--   breakOn "::" "a::b::c" == ("a", "::b::c")
--   breakOn "/" "foobar"   == ("foobar", "")
--   </pre>
--   
--   Laws:
--   
--   <pre>
--   \needle haystack -&gt; let (prefix,match) = breakOn needle haystack in prefix ++ match == haystack
--   </pre>
breakOn :: Eq a => [a] -> [a] -> ([a], [a])

-- | Similar to <a>breakOn</a>, but searches from the end of the string.
--   
--   The first element of the returned tuple is the prefix of
--   <tt>haystack</tt> up to and including the last match of
--   <tt>needle</tt>. The second is the remainder of <tt>haystack</tt>,
--   following the match.
--   
--   <pre>
--   breakOnEnd "::" "a::b::c" == ("a::b::", "c")
--   </pre>
breakOnEnd :: Eq a => [a] -> [a] -> ([a], [a])

-- | Break a list into pieces separated by the first list argument,
--   consuming the delimiter. An empty delimiter is invalid, and will cause
--   an error to be raised.
--   
--   Examples:
--   
--   <pre>
--   splitOn "\r\n" "a\r\nb\r\nd\r\ne" == ["a","b","d","e"]
--   splitOn "aaa"  "aaaXaaaXaaaXaaa"  == ["","X","X","X",""]
--   splitOn "x"    "x"                == ["",""]
--   splitOn "x"    ""                 == [""]
--   </pre>
--   
--   and
--   
--   <pre>
--   \s x -&gt; s /= "" ==&gt; intercalate s (splitOn s x) == x
--   \c x -&gt; splitOn [c] x                           == split (==c) x
--   </pre>
splitOn :: Eq a => [a] -> [a] -> [[a]]

-- | Splits a list into components delimited by separators, where the
--   predicate returns True for a separator element. The resulting
--   components do not contain the separators. Two adjacent separators
--   result in an empty component in the output. eg.
--   
--   <pre>
--   split (=='a') "aabbaca" == ["","","bb","c",""]
--   split (=='a') ""        == [""]
--   </pre>
split :: (a -> Bool) -> [a] -> [[a]]
chunksOf :: Int -> [a] -> [[a]]

module Data.IORef.Extra

-- | Strict version of <a>modifyIORef</a>
modifyIORef' :: IORef a -> (a -> a) -> IO ()
writeIORef' :: IORef a -> a -> IO ()

-- | Strict version of <a>atomicModifyIORef</a>. This forces both the value
--   stored in the <a>IORef</a> as well as the value returned.
atomicModifyIORef' :: IORef a -> (a -> (a, b)) -> IO b

-- | Variant of <a>writeIORef</a> with the "barrier to reordering" property
--   that <a>atomicModifyIORef</a> has.
atomicWriteIORef :: IORef a -> a -> IO ()
atomicWriteIORef' :: IORef a -> a -> IO ()

module Data.Either.Extra
isLeft :: Either t t1 -> Bool
isRight :: Either t t1 -> Bool
fromLeft :: Either t t1 -> t
fromRight :: Either t t1 -> t1
fromEither :: Either a a -> a

module Control.Monad.Extra
whenJust :: Applicative m => Maybe a -> (a -> m ()) -> m ()
unit :: m () -> m ()
partitionM :: Monad m => (a -> m Bool) -> [a] -> m ([a], [a])
concatMapM :: Monad m => (a -> m [b]) -> [a] -> m [b]
loopM :: Monad m => (a -> m (Either a b)) -> a -> m b
whileM :: Monad m => m Bool -> m ()
ifM :: Monad m => m Bool -> m a -> m a -> m a
notM :: Functor m => m Bool -> m Bool
(||^) :: Monad m => m Bool -> m Bool -> m Bool
(&&^) :: Monad m => m Bool -> m Bool -> m Bool
orM :: Monad m => [m Bool] -> m Bool
andM :: Monad m => [m Bool] -> m Bool
anyM :: Monad m => (a -> m Bool) -> [a] -> m Bool
allM :: Monad m => (a -> m Bool) -> [a] -> m Bool
findM :: Monad m => (a -> m Bool) -> [a] -> m (Maybe a)
firstJustM :: Monad m => (a -> m (Maybe b)) -> [a] -> m (Maybe b)

module System.Directory.Extra
withCurrentDirectory :: FilePath -> IO a -> IO a
getDirectoryContentsRecursive :: FilePath -> IO [FilePath]

module Control.Exception.Extra
retry :: Int -> IO a -> IO a

-- | Print an exception, but if that exception itself contains exceptions,
--   simply print <tt>&lt;NestedException&gt;</tt>. Since Haskell is a lazy
--   language it is possible to throw exceptions that are themselves
--   undefined. This function is useful to report them to users.
showException :: SomeException -> IO String

-- | Ignore any exceptions thrown by the action and continue as normal.
ignore :: IO () -> IO ()
catch_ :: IO a -> (SomeException -> IO a) -> IO a
handle_ :: (SomeException -> IO a) -> IO a -> IO a
try_ :: IO a -> IO (Either SomeException a)
catchJust_ :: (SomeException -> Maybe b) -> IO a -> (b -> IO a) -> IO a
handleJust_ :: (SomeException -> Maybe b) -> (b -> IO a) -> IO a -> IO a
tryJust_ :: (SomeException -> Maybe b) -> IO a -> IO (Either b a)
catchBool :: Exception e => (e -> Bool) -> IO a -> (e -> IO a) -> IO a
handleBool :: Exception e => (e -> Bool) -> (e -> IO a) -> IO a -> IO a
tryBool :: Exception e => (e -> Bool) -> IO a -> IO (Either e a)

module System.Info.Extra
isWindows :: Bool
getProcessorCount :: IO Int


-- | More advanced temporary file manipulation functions can be found in
--   the <tt>exceptions</tt> package.
module System.IO.Extra
readFileEncoding :: TextEncoding -> FilePath -> IO String
readFileUTF8 :: FilePath -> IO String
readFileBinary :: FilePath -> IO String
readFile' :: FilePath -> IO String
readFileEncoding' :: TextEncoding -> FilePath -> IO String
readFileUTF8' :: FilePath -> IO String
readFileBinary' :: FilePath -> IO String
writeFileEncoding :: TextEncoding -> FilePath -> String -> IO ()
writeFileUTF8 :: FilePath -> String -> IO ()
writeFileBinary :: FilePath -> String -> IO ()
withTempFile :: (FilePath -> IO a) -> IO a
withTempDir :: (FilePath -> IO a) -> IO a
captureOutput :: IO () -> IO String
withBuffering :: Handle -> BufferMode -> IO a -> IO a

module Control.Concurrent.Extra

-- | On GHC 7.6 and above with the <tt>-threaded</tt> flag, brackets a call
--   to <a>setNumCapabilities</a>. On lower versions (which lack
--   <a>setNumCapabilities</a>) this function just runs the argument
--   action.
withNumCapabilities :: Int -> IO a -> IO a

-- | A version of <a>setNumCapabilities</a> that works on all versions of
--   GHC, but has no effect before GHC 7.6.
setNumCapabilities :: Int -> IO ()

module Extra

-- | On GHC 7.6 and above with the <tt>-threaded</tt> flag, brackets a call
--   to <a>setNumCapabilities</a>. On lower versions (which lack
--   <a>setNumCapabilities</a>) this function just runs the argument
--   action.
withNumCapabilities :: Int -> IO a -> IO a

-- | A version of <a>setNumCapabilities</a> that works on all versions of
--   GHC, but has no effect before GHC 7.6.
setNumCapabilities :: Int -> IO ()
retry :: Int -> IO a -> IO a

-- | Print an exception, but if that exception itself contains exceptions,
--   simply print <tt>&lt;NestedException&gt;</tt>. Since Haskell is a lazy
--   language it is possible to throw exceptions that are themselves
--   undefined. This function is useful to report them to users.
showException :: SomeException -> IO String

-- | Ignore any exceptions thrown by the action and continue as normal.
ignore :: IO () -> IO ()
catch_ :: IO a -> (SomeException -> IO a) -> IO a
handle_ :: (SomeException -> IO a) -> IO a -> IO a
try_ :: IO a -> IO (Either SomeException a)
catchJust_ :: (SomeException -> Maybe b) -> IO a -> (b -> IO a) -> IO a
handleJust_ :: (SomeException -> Maybe b) -> (b -> IO a) -> IO a -> IO a
tryJust_ :: (SomeException -> Maybe b) -> IO a -> IO (Either b a)
catchBool :: Exception e => (e -> Bool) -> IO a -> (e -> IO a) -> IO a
handleBool :: Exception e => (e -> Bool) -> (e -> IO a) -> IO a -> IO a
tryBool :: Exception e => (e -> Bool) -> IO a -> IO (Either e a)
whenJust :: Applicative m => Maybe a -> (a -> m ()) -> m ()
unit :: m () -> m ()
partitionM :: Monad m => (a -> m Bool) -> [a] -> m ([a], [a])
concatMapM :: Monad m => (a -> m [b]) -> [a] -> m [b]
loopM :: Monad m => (a -> m (Either a b)) -> a -> m b
whileM :: Monad m => m Bool -> m ()
ifM :: Monad m => m Bool -> m a -> m a -> m a
notM :: Functor m => m Bool -> m Bool
(||^) :: Monad m => m Bool -> m Bool -> m Bool
(&&^) :: Monad m => m Bool -> m Bool -> m Bool
orM :: Monad m => [m Bool] -> m Bool
andM :: Monad m => [m Bool] -> m Bool
anyM :: Monad m => (a -> m Bool) -> [a] -> m Bool
allM :: Monad m => (a -> m Bool) -> [a] -> m Bool
findM :: Monad m => (a -> m Bool) -> [a] -> m (Maybe a)
firstJustM :: Monad m => (a -> m (Maybe b)) -> [a] -> m (Maybe b)
isLeft :: Either t t1 -> Bool
isRight :: Either t t1 -> Bool
fromLeft :: Either t t1 -> t
fromRight :: Either t t1 -> t1
fromEither :: Either a a -> a

-- | Strict version of <a>modifyIORef</a>
modifyIORef' :: IORef a -> (a -> a) -> IO ()
writeIORef' :: IORef a -> a -> IO ()

-- | Strict version of <a>atomicModifyIORef</a>. This forces both the value
--   stored in the <a>IORef</a> as well as the value returned.
atomicModifyIORef' :: IORef a -> (a -> (a, b)) -> IO b

-- | Variant of <a>writeIORef</a> with the "barrier to reordering" property
--   that <a>atomicModifyIORef</a> has.
atomicWriteIORef :: IORef a -> a -> IO ()
atomicWriteIORef' :: IORef a -> a -> IO ()
lower :: String -> String
upper :: String -> String
strip :: String -> String
stripStart :: String -> String
stripEnd :: String -> String
dropAround :: (a -> Bool) -> [a] -> [a]
word1 :: String -> (String, String)
drop1 :: [a] -> [a]
list :: b -> (a -> [a] -> b) -> [a] -> b
uncons :: [a] -> Maybe (a, [a])
unsnoc :: [a] -> Maybe ([a], a)
cons :: a -> [a] -> [a]
snoc :: [a] -> a -> [a]
groupSort :: Ord k => [(k, v)] -> [(k, [v])]
groupSortOn :: Ord a => (k -> a) -> [(k, v)] -> [(k, [v])]
nubOn :: Eq b => (a -> b) -> [a] -> [a]
groupOn :: Eq b => (a -> b) -> [a] -> [[a]]
sortOn :: Ord b => (a -> b) -> [a] -> [a]
chop :: ([a] -> (b, [a])) -> [a] -> [b]
for :: [a] -> (a -> b) -> [b]
rep :: Eq a => a -> a -> a -> a
reps :: Eq a => a -> a -> [a] -> [a]
disjoint :: Eq a => [a] -> [a] -> Bool
distinct :: Eq a => [a] -> Bool
dropEnd :: Int -> [a] -> [a]
takeEnd :: Int -> [a] -> [a]
breakEnd :: (a -> Bool) -> [a] -> ([a], [a])
spanEnd :: (a -> Bool) -> [a] -> ([a], [a])

-- | The <a>dropWhileEnd</a> function drops the largest suffix of a list in
--   which the given predicate holds for all elements. For example:
--   
--   <pre>
--   dropWhileEnd isSpace "foo\n" == "foo"
--   dropWhileEnd isSpace "foo bar" == "foo bar"
--   dropWhileEnd isSpace ("foo\n" ++ undefined) == "foo" ++ undefined
--   </pre>
dropWhileEnd :: (a -> Bool) -> [a] -> [a]
takeWhileEnd :: (a -> Bool) -> [a] -> [a]

-- | Return the prefix of the second string if its suffix matches the
--   entire first string.
--   
--   Examples:
--   
--   <pre>
--   stripSuffix "bar" "foobar" == Just "foo"
--   stripSuffix ""    "baz"    == Just "baz"
--   stripSuffix "foo" "quux"   == Nothing
--   </pre>
stripSuffix :: Eq a => [a] -> [a] -> Maybe [a]
concatUnzip :: [([a], [b])] -> ([a], [b])
merge :: Ord a => [a] -> [a] -> [a]
mergeBy :: (a -> a -> Ordering) -> [a] -> [a] -> [a]
replace :: String -> String -> String -> String
wordsBy :: (a -> Bool) -> [a] -> [[a]]
linesBy :: (a -> Bool) -> [a] -> [[a]]
firstJust :: (a -> Maybe b) -> [a] -> Maybe b

-- | Find the first instance of <tt>needle</tt> in <tt>haystack</tt>. The
--   first element of the returned tuple is the prefix of <tt>haystack</tt>
--   before <tt>needle</tt> is matched. The second is the remainder of
--   <tt>haystack</tt>, starting with the match.
--   
--   Examples:
--   
--   <pre>
--   breakOn "::" "a::b::c" == ("a", "::b::c")
--   breakOn "/" "foobar"   == ("foobar", "")
--   </pre>
--   
--   Laws:
--   
--   <pre>
--   \needle haystack -&gt; let (prefix,match) = breakOn needle haystack in prefix ++ match == haystack
--   </pre>
breakOn :: Eq a => [a] -> [a] -> ([a], [a])

-- | Similar to <a>breakOn</a>, but searches from the end of the string.
--   
--   The first element of the returned tuple is the prefix of
--   <tt>haystack</tt> up to and including the last match of
--   <tt>needle</tt>. The second is the remainder of <tt>haystack</tt>,
--   following the match.
--   
--   <pre>
--   breakOnEnd "::" "a::b::c" == ("a::b::", "c")
--   </pre>
breakOnEnd :: Eq a => [a] -> [a] -> ([a], [a])

-- | Break a list into pieces separated by the first list argument,
--   consuming the delimiter. An empty delimiter is invalid, and will cause
--   an error to be raised.
--   
--   Examples:
--   
--   <pre>
--   splitOn "\r\n" "a\r\nb\r\nd\r\ne" == ["a","b","d","e"]
--   splitOn "aaa"  "aaaXaaaXaaaXaaa"  == ["","X","X","X",""]
--   splitOn "x"    "x"                == ["",""]
--   splitOn "x"    ""                 == [""]
--   </pre>
--   
--   and
--   
--   <pre>
--   \s x -&gt; s /= "" ==&gt; intercalate s (splitOn s x) == x
--   \c x -&gt; splitOn [c] x                           == split (==c) x
--   </pre>
splitOn :: Eq a => [a] -> [a] -> [[a]]

-- | Splits a list into components delimited by separators, where the
--   predicate returns True for a separator element. The resulting
--   components do not contain the separators. Two adjacent separators
--   result in an empty component in the output. eg.
--   
--   <pre>
--   split (=='a') "aabbaca" == ["","","bb","c",""]
--   split (=='a') ""        == [""]
--   </pre>
split :: (a -> Bool) -> [a] -> [[a]]
chunksOf :: Int -> [a] -> [[a]]
dupe :: a -> (a, a)
fst3 :: (a, b, c) -> a
snd3 :: (a, b, c) -> b
thd3 :: (a, b, c) -> c
concat2 :: [([a], [b])] -> ([a], [b])
concat3 :: [([a], [b], [c])] -> ([a], [b], [c])
showDP :: RealFloat a => Int -> a -> String
intToDouble :: Int -> Double
intToFloat :: Int -> Float
floatToDouble :: Float -> Double
doubleToFloat :: Double -> Float
withCurrentDirectory :: FilePath -> IO a -> IO a
getDirectoryContentsRecursive :: FilePath -> IO [FilePath]

-- | Returns the absolute pathname of the current executable.
--   
--   Note that for scripts and interactive sessions, this is the path to
--   the interpreter (e.g. ghci.)
getExecutablePath :: IO FilePath

-- | Return the value of the environment variable <tt>var</tt>, or
--   <tt>Nothing</tt> if there is no such value.
--   
--   For POSIX users, this is equivalent to <a>getEnv</a>.
lookupEnv :: String -> IO (Maybe String)
isWindows :: Bool
getProcessorCount :: IO Int
readFileEncoding :: TextEncoding -> FilePath -> IO String
readFileUTF8 :: FilePath -> IO String
readFileBinary :: FilePath -> IO String
readFile' :: FilePath -> IO String
readFileEncoding' :: TextEncoding -> FilePath -> IO String
readFileUTF8' :: FilePath -> IO String
readFileBinary' :: FilePath -> IO String
writeFileEncoding :: TextEncoding -> FilePath -> String -> IO ()
writeFileUTF8 :: FilePath -> String -> IO ()
writeFileBinary :: FilePath -> String -> IO ()
withTempFile :: (FilePath -> IO a) -> IO a
withTempDir :: (FilePath -> IO a) -> IO a
captureOutput :: IO () -> IO String
withBuffering :: Handle -> BufferMode -> IO a -> IO a
sleep :: Double -> IO ()
subtractTime :: UTCTime -> UTCTime -> Double
showTime :: Double -> String

-- | Call once at the start, then call repeatedly to get Time values out
offsetTime :: IO (IO Double)

-- | Like offsetTime, but results will never decrease (though they may stay
--   the same)
offsetTimeIncrease :: IO (IO Double)
duration :: IO a -> IO (Double, a)