!f0H      !"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdef ghijklmnopqrstuvwxyz{|} ~  Safe extra#Evaluates the value before calling .extra#Evaluates the value before calling . Safe extraO(n)(. Append an element to a non-empty list. ((1 :| [2,3]) |> 4 |> 5 == 1 :| [2,3,4,5]extra Synonym for .extraO(n). Append an element to a list. #[1,2,3] |: 4 |> 5 == 1 :| [2,3,4,5] extra"Append a list to a non-empty list. ,appendl (1 :| [2,3]) [4,5] == 1 :| [2,3,4,5] extra"Append a non-empty list to a list. ,appendr [1,2,3] (4 :| [5]) == 1 :| [2,3,4,5] extraSort by comparing the results of a function applied to each element. The sort is stable, and the function is evaluated only once for each element. extraReturn the union of two non-empty lists. Duplicates, and elements of the first list, are removed from the the second list, but if the first list contains duplicates, so will the result. D(1 :| [3, 5, 3]) `union` (4 :| [5, 3, 5, 2]) == 1 :| [3, 5, 3, 4, 2] extraThe non-overloaded version of  .extra(The largest element of a non-empty list.extra&The least element of a non-empty list.extraYThe largest element of a non-empty list with respect to the given comparison function.extraWThe least element of a non-empty list with respect to the given comparison function.extra A version of 6 where the comparison is done on some extracted value.extra A version of 6 where the comparison is done on some extracted value.H       55Safe/ extra%Update the first component of a pair. #first succ (1,"test") == (2,"test")extra&Update the second component of a pair. 'second reverse (1,"test") == (1,"tset")extraiGiven two functions, apply one to the first component and one to the second. A specialised version of . +(succ *** reverse) (1,"test") == (2,"tset")extraaGiven two functions, apply both to a single argument to form a pair. A specialised version of . (succ &&& pred) 1 == (2,0)extra%Duplicate a single value into a pair. dupe 12 == (12, 12)extra5Apply a single function to both components of a pair. both succ (1,2) == (2,3)extra Extract the  of a triple.extra Extract the  of a triple.extra&Extract the final element of a triple.extra5Converts an uncurried function to a curried function.extra6Converts a curried function to a function on a triple. 33Safe0$ !"#$%&'()*+,-./0123456789:;<=>?@ABSafe7extra2Show a number to a fixed number of decimal places. @showDP 4 pi == "3.1416" showDP 0 pi == "3" showDP 2 3 == "3.00" extra;Specialised numeric conversion, type restricted version of C.!extra;Specialised numeric conversion, type restricted version of C."extra;Specialised numeric conversion, type restricted version of D.#extra;Specialised numeric conversion, type restricted version of D.1EFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnop !"# !"#Safe,H>$extraA constraint which documents that a function is partial, and on GHC 8.0 and above produces a stack trace on failure. For example:  myHead :: $7 => [a] -> a myHead [] = error "bad" myHead (x:xs) = x  When using $B with GHC 7.8 or below you need to enable the language feature ConstraintKinds, e.g.  {-# LANGUAGE ConstraintKinds #-} at the top of the file.$Safe,P ?%extraaApply some operation repeatedly, producing an element of output and the remainder of the list. \xs -> repeatedly (splitAt 3) xs == chunksOf 3 xs \xs -> repeatedly word1 (trim xs) == words xs \xs -> repeatedly line1 xs == lines xs&extra DEPRECATED Use flip map, directly, since this function clashes with Data.Traversable.for.Flipped version of q.'extra3Are two lists disjoint, with no elements in common. >disjoint [1,2,3] [4,5] == True disjoint [1,2,3] [4,1] == False(extra1Is there any element which occurs more than once. anySame [1,1,2] == True anySame [1,2,3] == False anySame (1:2:1:undefined) == True anySame [] == False \xs -> anySame xs == (length (nub xs) < length xs))extraAre all elements the same. allSame [1,1,2] == False allSame [1,1,1] == True allSame [1] == True allSame [] == True allSame (1:1:2:undefined) == False \xs -> allSame xs == (length (nub xs) <= 1)*extraA composition of r and s. KnotNull [] == False notNull [1] == True \xs -> notNull xs == not (null xs)+extra*Non-recursive transform over a list, like t. list 1 (\v _ -> v - 2) [5,6,7] == 3 list 1 (\v _ -> v - 2) [] == 1 \nil cons xs -> maybe nil (uncurry cons) (uncons xs) == list nil cons xs,extraIf the list is empty returns u, otherwise returns the v and the w. unsnoc "test" == Just ("tes",'t') unsnoc "" == Nothing \xs -> unsnoc xs == if null xs then Nothing else Just (init xs, last xs)-extra=Append an element to the start of a list, an alias for '(:)'. Ccons 't' "est" == "test" \x xs -> uncons (cons x xs) == Just (x,xs).extra.Append an element to the end of a list, takes O(n) time. Csnoc "tes" 't' == "test" \xs x -> unsnoc (snoc xs x) == Just (xs,x)/extra3Take a number of elements from the end of the list. takeEnd 3 "hello" == "llo" takeEnd 5 "bye" == "bye" takeEnd (-1) "bye" == "" \i xs -> takeEnd i xs `isSuffixOf` xs \i xs -> length (takeEnd i xs) == min (max 0 i) (length xs)0extra3Drop a number of elements from the end of the list. dropEnd 3 "hello" == "he" dropEnd 5 "bye" == "" dropEnd (-1) "bye" == "bye" \i xs -> dropEnd i xs `isPrefixOf` xs \i xs -> length (dropEnd i xs) == max 0 (length xs - max 0 i) \i -> take 3 (dropEnd 5 [i..]) == take 3 [i..]1extra1 n xs> returns a split where the second element tries to contain n elements. splitAtEnd 3 "hello" == ("he","llo") splitAtEnd 3 "he" == ("", "he") \i xs -> uncurry (++) (splitAt i xs) == xs \i xs -> splitAtEnd i xs == (dropEnd i xs, takeEnd i xs)2extraxe against an enumeration. Never truncates the output - raises an error if the enumeration runs out. G\i xs -> zip [i..] xs == zipFrom i xs zipFrom False [1..3] == undefined3extra2u generalised to any combining operation. Never truncates the output - raises an error if the enumeration runs out. -\i xs -> zipWithFrom (,) i xs == zipFrom i xs4extra A merging of y and z. 4concatUnzip [("a","AB"),("bc","C")] == ("abc","ABC")5extra A merging of { and z. DconcatUnzip3 [("a","AB",""),("bc","C","123")] == ("abc","ABC","123")6extra A version of | operating from the end. $takeWhileEnd even [2,3,4,6] == [4,6]7extra.Remove spaces from the start of a string, see 9.8extra,Remove spaces from the end of a string, see 9.9extra=Remove spaces from either side of a string. A combination of 8 and 7. trim " hello " == "hello" trimStart " hello " == "hello " trimEnd " hello " == " hello" \s -> trim s == trimEnd (trimStart s):extraConvert a string to lower case. 9lower "This is A TEST" == "this is a test" lower "" == "";extraConvert a string to upper case. 9upper "This is A TEST" == "THIS IS A TEST" upper "" == ""<extraSplit the first word off a string. Useful for when starting to parse the beginning of a string, but you want to accurately preserve whitespace in the rest of the string. word1 "" == ("", "") word1 "keyword rest of string" == ("keyword","rest of string") word1 " keyword\n rest of string" == ("keyword","rest of string") \s -> fst (word1 s) == concat (take 1 $ words s) \s -> words (snd $ word1 s) == drop 1 (words s)=extra"Split the first line off a string. line1 "" == ("", "") line1 "test" == ("test","") line1 "test\n" == ("test","") line1 "test\nrest" == ("test","rest") line1 "test\nrest\nmore" == ("test","rest\nmore")>extraFEscape a string such that it can be inserted into an HTML document or "M attribute without any special interpretation. This requires escaping the <, >, & and ") characters. Note that it will escape " and 'G even though that is not required in an HTML body (but is not harmful). escapeHTML "this is a test" == "this is a test" escapeHTML "<b>\"g&t\"</n>" == "&lt;b&gt;&quot;g&amp;t&quot;&lt;/n&gt;" escapeHTML "t'was another test" == "t&#39;was another test"?extra Invert of >& (does not do general HTML unescaping) )\xs -> unescapeHTML (escapeHTML xs) == xs@extraEscape a string so it can form part of a JSON literal. This requires escaping the special whitespace and control characters. Additionally, Note that it does not( add quote characters around the string. escapeJSON "this is a test" == "this is a test" escapeJSON "\ttab\nnewline\\" == "\\ttab\\nnewline\\\\" escapeJSON "\ESC[0mHello" == "\\u001b[0mHello"Aextra&General JSON unescaping, inversion of @ and all other JSON escapes. )\xs -> unescapeJSON (escapeJSON xs) == xsBextra A version of }4 where the equality is done on some extracted value.Cextra A version of ~8 where the equality is done on some extracted value. nubOn f is equivalent to  nubBy ((==)  f):, but has the performance advantage of only evaluating f, once for each element in the input list.Dextra A version of 6 where the comparison is done on some extracted value.Eextra A version of 6 where the comparison is done on some extracted value.FextraA combination of } and . groupSort [(1,'t'),(3,'t'),(2,'e'),(2,'s')] == [(1,"t"),(2,"es"),(3,"t")] \xs -> map fst (groupSort xs) == sort (nub (map fst xs)) \xs -> concatMap snd (groupSort xs) == map snd (sortOn fst xs)GextraA combination of } and *, using a part of the value to compare on. UgroupSortOn length ["test","of","sized","item"] == [["of"],["test","item"],["sized"]]HextraA combination of } and ", using a predicate to compare on. dgroupSortBy (compare `on` length) ["test","of","sized","item"] == [["of"],["test","item"],["sized"]]Iextra0Merge two lists which are assumed to be ordered. Rmerge "ace" "bd" == "abcde" \xs ys -> merge (sort xs) (sort ys) == sort (xs ++ ys)JextraLike I&, but with a custom ordering function.Kextra]Replace a subsequence everywhere it occurs. The first argument must not be the empty list. replace "el" "_" "Hello Bella" == "H_lo B_la" replace "el" "e" "Hello" == "Helo" replace "" "e" "Hello" == undefined \xs ys -> not (null xs) ==> replace xs xs ys == ysLextraBreak, but from the end. breakEnd isLower "youRE" == ("you","RE") breakEnd isLower "youre" == ("youre","") breakEnd isLower "YOURE" == ("","YOURE") \f xs -> breakEnd (not . f) xs == spanEnd f xsMextraSpan, but from the end. spanEnd isUpper "youRE" == ("you","RE") spanEnd (not . isSpace) "x y z" == ("x y ","z") \f xs -> uncurry (++) (spanEnd f xs) == xs \f xs -> spanEnd f xs == swap (both reverse (span f (reverse xs)))Nextra A variant of p with a custom test. In particular, adjacent separators are discarded, as are leading or trailing separators. ]wordsBy (== ':') "::xyz:abc::123::" == ["xyz","abc","123"] \s -> wordsBy isSpace s == words sOextra A variant of ] with a custom test. In particular, if there is a trailing separator it will be discarded. linesBy (== ':') "::xyz:abc::123::" == ["","","xyz","abc","","123",""] \s -> linesBy (== '\n') s == lines s linesBy (== ';') "my;list;here;" == ["my","list","here"]PextraAFind the first element of a list for which the operation returns 2, along with the result of the operation. Like  but useful where the function also computes some expensive information that can be reused. Particular useful when the function is monadic, see  firstJustM. RfirstJust id [Nothing,Just 3] == Just 3 firstJust id [Nothing,Nothing] == NothingQextraEquivalent to drop 1., but likely to be faster and a single lexeme. Mdrop1 "" == "" drop1 "test" == "est" \xs -> drop 1 xs == drop1 xsRextra Version on  generalised to a  rather than just a list. JmconcatMap Sum [1,2,3] == Sum 6 \f xs -> mconcatMap f xs == concatMap f xsSextraFind the first instance of needle in haystack=. The first element of the returned tuple is the prefix of haystack before needle. is matched. The second is the remainder of haystack6, starting with the match. If you want the remainder without the match, use [. breakOn "::" "a::b::c" == ("a", "::b::c") breakOn "/" "foobar" == ("foobar", "") \needle haystack -> let (prefix,match) = breakOn needle haystack in prefix ++ match == haystackTextra Similar to S+, but searches from the end of the string.9The first element of the returned tuple is the prefix of haystack( up to and including the last match of needle#. The second is the remainder of haystack, following the match. ,breakOnEnd "::" "a::b::c" == ("a::b::", "c")UextraBreak 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. <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" "" == [""] \s x -> s /= "" ==> intercalate s (splitOn s x) == x \c x -> splitOn [c] x == split (==c) xVextraSplits 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. split (== 'a') "aabbaca" == ["","","bb","c",""] split (== 'a') "" == [""] split (== ':') "::xyz:abc::123::" == ["","","xyz","abc","","123","",""] split (== ',') "my,list,here" == ["my","list","here"]Wextra A version of ; but with different strictness properties. The function [ can be used on an infinite list and tests the property on each character. In contrast, Wo is strict in the spine of the list but only tests the trailing suffix. This version usually outperforms t if the list is short or the test is expensive. Note the tests below cover both the prime and non-prime variants. dropWhileEnd isSpace "ab cde " == "ab cde" dropWhileEnd' isSpace "ab cde " == "ab cde" last (dropWhileEnd even [undefined,3]) == undefined last (dropWhileEnd' even [undefined,3]) == 3 head (dropWhileEnd even (3:undefined)) == 3 head (dropWhileEnd' even (3:undefined)) == undefinedXextra|Drops the given prefix from a list. It returns the original sequence if the sequence doesn't start with the given prefix. MdropPrefix "Mr. " "Mr. Men" == "Men" dropPrefix "Mr. " "Dr. Men" == "Dr. Men"YextrazDrops the given suffix from a list. It returns the original sequence if the sequence doesn't end with the given suffix. dropSuffix "!" "Hello World!" == "Hello World" dropSuffix "!" "Hello World!!" == "Hello World!" dropSuffix "!" "Hello World." == "Hello World."ZextraTReturn the prefix of the second list if its suffix matches the entire first list. Examples: wstripSuffix "bar" "foobar" == Just "foo" stripSuffix "" "baz" == Just "baz" stripSuffix "foo" "quux" == Nothing[extra@Return the the string before and after the search string, or u% if the search string is not present. Examples: TstripInfix "::" "a::b::c" == Just ("a", "b::c") stripInfix "/" "foobar" == Nothing\extra Similar to [+, but searches from the end of the string. 2stripInfixEnd "::" "a::b::c" == Just ("a::b", "c")]extraSplit a list into chunks of a given size. The last chunk may contain fewer than n elements. The chunk size must be positive. chunksOf 3 "my test" == ["my ","tes","t"] chunksOf 3 "mytest" == ["myt","est"] chunksOf 8 "" == [] chunksOf 0 "test" == undefined^extra O(n log n). The ^ function sorts and removes duplicate elements from a list. In particular, it keeps only the first occurrence of each element. HnubSort "this is a test" == " aehist" \xs -> nubSort xs == nub (sort xs)_extra A version of ^* which operates on a portion of the value. >nubSortOn length ["a","test","of","this"] == ["a","of","test"]`extra A version of ^ with a custom predicate. MnubSortBy (compare `on` length) ["a","test","of","this"] == ["a","of","test"]aextra O(n log n). The a function removes duplicate elements from a list. In particular, it keeps only the first occurrence of each element. Unlike the standard ~$ operator, this version requires an 7 instance and consequently runs asymptotically faster. onubOrd "this is a test" == "this ae" nubOrd (take 4 ("this" ++ undefined)) == "this" \xs -> nubOrd xs == nub xsbextra A version of a* which operates on a portion of the value. =nubOrdOn length ["a","test","of","this"] == ["a","test","of"]cextra A version of a with a custom predicate. LnubOrdBy (compare `on` length) ["a","test","of","this"] == ["a","test","of"]xqsz}~{y|vw%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abc?:;978<=>@?A0/1LMW6Z[\XYNOSTUV]*+,-.QRFGHacbCB^`_DE')(%&P4523KIJ Safe,RfextraRead a  or throw an exception. G\x -> readVersion (showVersion x) == x readVersion "hello" == undefinedffSafe,)gextraThe g( function extracts the element out of a + and throws an error if its argument is . Much like fromJust=, using this function in polished code is usually a bad idea. E\x -> fromLeft' (Left x) == x \x -> fromLeft' (Right x) == undefinedhextraThe h( function extracts the element out of a + and throws an error if its argument is . Much like fromJust=, using this function in polished code is usually a bad idea. G\x -> fromRight' (Right x) == x \x -> fromRight' (Left x) == undefinediextraPull the value out of an / where both alternatives have the same type. ?\x -> fromEither (Left x ) == x \x -> fromEither (Right x) == xjextraGiven a , convert it to an (, providing a suitable value for the  should the value be u. S\a b -> maybeToEither a (Just b) == Right b \a -> maybeToEither a Nothing == Left akextra Given an , convert it to a , where  becomes u. O\x -> eitherToMaybe (Left x) == Nothing \x -> eitherToMaybe (Right x) == Just xlextraThe l[ function takes a function and applies it to an Either value iff the value takes the form  _. ImapLeft show (Left 1) == Left "1" mapLeft show (Right True) == Right TruemextraThe m[ function takes a function and applies it to an Either value iff the value takes the form  _. KmapRight show (Left 1) == Left 1 mapRight show (Right True) == Right "True"ghijklm ighkjlmSafe,XFnextra[Fully evaluate an input String. If the String contains embedded exceptions it will produce  <Exception>. (stringException "test" == return "test" stringException ("test" ++ undefined) == return "test<Exception>" stringException ("test" ++ undefined ++ "hello") == return "test<Exception>" stringException ['t','e','s','t',undefined] == return "test<Exception>"oextra@Show a value, but if the result contains exceptions, produce  <Exception> . Defined as n . show. Particularly useful for printing exceptions to users, remembering that exceptions can themselves contain undefined values.pextra+Ignore any exceptions thrown by the action. ?ignore (print 1) == print 1 ignore (fail "die") == return ()qextraLike error, but in the  monad. Note that while  in  raises an , this function raises an  exception. :try (errorIO "Hello") == return (Left (ErrorCall "Hello"))rextraRetry an operation at most n times (n2 must be positive). If the operation fails the n+th time it will throw that final exception. Dretry 1 (print "x") == print "x" retry 3 (fail "die") == fail "die"sextraRetry an operation at most n times (nh must be positive), while the exception value and type match a predicate. If the operation fails the n+th time it will throw that final exception.textra A version of  without the  context, restricted to , so catches all exceptions.uextraLike t but for vextraLike t but for wextraLike t but for xextraLike t but for yextraLike t but for  zextrapCatch an exception if the predicate passes, then call the handler with the original exception. As an example: ZreadFileExists x == catchBool isDoesNotExistError (readFile "myfile") (const $ return "") {extraLike z but for .|extraLike z but for .j      !"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWX$nopqrstuvwxyz{|$rsonqptvxuwyz{| Safe,N}extraPerform some operation on , given the field inside the . GwhenJust Nothing print == return () whenJust (Just 1) print == print 1~extraLike }$, but where the test can be monadic.extraLike Y, but return either u if the predicate was Z, of $ with the result of the computation. \whenMaybe True (print 1) == fmap Just (print 1) whenMaybe False (print 1) == return NothingextraLike $, but where the test can be monadic.extra>The identity function which requires the inner argument to be ()7. Useful for functions with overloaded return types. \(x :: Maybe ()) -> unit x == xextraMonadic generalisation of t.extraMonadic generalisation of [.extraMonadic generalisation of .extra A variant of \H that has no base case, and thus may only be applied to non-empty lists. Yfold1M (\x y -> Just x) [] == undefined fold1M (\x y -> Just $ x + y) [1, 2, 3] == Just 6extraLike  but discards the result.extra A version of  partition% that works with a monadic predicate. cpartitionM (Just . even) [1,2,3] == Just ([2], [1,3]) partitionM (const Nothing) [1,2,3] == Nothingextra A version of % that works with a monadic predicate.extraLike I, but has its arguments flipped, so can be used instead of the common fmap concat $ forM pattern.extra A version of  mconcatMap% that works with a monadic predicate.extra A version of ]% that works with a monadic predicate.extra1A looping operation, where the predicate returns # as a seed for the next loop or  to abort the loop. Floop (\x -> if x < 10 then Left $ x * 2 else Right $ show x) 1 == "16"extraA monadic version of , where the predicate returns # as a seed for the next loop or  to abort the loop.extra+Keep running an operation until it becomes Z. As an example: IwhileM $ do sleep 0.1; notM $ doesFileExist "foo.txt" readFile "foo.txt" 8If you need some state persisted between each test, use .extraLike Y$, but where the test can be monadic.extraLike ^$, but where the test can be monadic.extraLike if$, but where the test can be monadic.extraLike r$, but where the test can be monadic.extra The lazy _C operator lifted to a monad. If the first argument evaluates to `. the second argument will not be evaluated. uJust True ||^ undefined == Just True Just False ||^ Just True == Just True Just False ||^ Just False == Just Falseextra The lazy aC operator lifted to a monad. If the first argument evaluates to Z. the second argument will not be evaluated. vJust False &&^ undefined == Just False Just True &&^ Just True == Just True Just True &&^ Just False == Just Falseextra A version of ; lifted to a monad. Retains the short-circuiting behaviour. anyM Just [False,True ,undefined] == Just True anyM Just [False,False,undefined] == undefined \(f :: Int -> Maybe Bool) xs -> anyM f xs == orM (map f xs)extra A version of ; lifted to a monad. Retains the short-circuiting behaviour. allM Just [True,False,undefined] == Just False allM Just [True,True ,undefined] == undefined \(f :: Int -> Maybe Bool) xs -> anyM f xs == orM (map f xs)extra A version of ; lifted to a monad. Retains the short-circuiting behaviour. orM [Just False,Just True ,undefined] == Just True orM [Just False,Just False,undefined] == undefined \xs -> Just (or xs) == orM (map Just xs)extra A version of ; lifted to a monad. Retains the short-circuiting behaviour. andM [Just True,Just False,undefined] == Just False andM [Just True,Just True ,undefined] == undefined \xs -> Just (and xs) == andM (map Just xs)extraLike find$, but where the test can be monadic. findM (Just . isUpper) "teST" == Just (Just 'S') findM (Just . isUpper) "test" == Just Nothing findM (Just . const True) ["x",undefined] == Just (Just "x")extraLike N, but also allows you to compute some additional information in the predicate.Hbcdefghijklm^nop\qrstuvwxyz{|}~Y}~}~ Safe,Pextra=Starts out empty, then is filled exactly once. As an example: bar <-  forkIO $ do ...; val <- ...;  bar val print =<<  bar PHere we create a barrier which will contain some computed value. A thread is forked to fill the barrier, while the main thread waits for it to complete. A barrier has similarities to a future or promise from other languages, has been known as an IVar in other Haskell work, and in some ways is like a manually managed thunk.extraLike an k, but must always be full. Used to operate on a mutable variable in a thread-safe way. As an example: hits <-  0 forkIO $ do ...;  hits (+1); ... i <-  hits print ("HITS",i) iHere we have a variable which we modify atomically, so modifications are not interleaved. This use of  never blocks on a put. No modifyVar operation should ever block, and they should always complete in a reasonable timeframe. A q should not be used to protect some external resource, only the variable contained within. Information from a 6 should not be subsequently inserted back into the .extraLike an u, but has no value. Used to guarantee single-threaded access, typically to some system resource. As an example: lock <-  let output = L . putStrLn forkIO $ do ...; output "hello" forkIO $ do ...; output "world" sHere we are creating a lock to ensure that when writing output our messages do not get interleaved. This use of  never blocks on a put. It is permissible, but rare, that a withLock contains a withLock inside it - but if so, watch out for deadlocks.extraOn GHC 7.6 and above with the  -threaded flag, brackets a call to #. On lower versions (which lack .) this function just runs the argument action.extraGiven an action, produce a wrapped action that runs at most once. If the function raises an exception, the same exception will be reraised each time. let x ||| y = do t1 <- onceFork x; t2 <- onceFork y; t1; t2 \(x :: IO Int) -> void (once x) == return () \(x :: IO Int) -> join (once x) == x \(x :: IO Int) -> (do y <- once x; y; y) == x \(x :: IO Int) -> (do y <- once x; y ||| y) == xextraLike H, but immediately starts running the computation on a background thread. Z\(x :: IO Int) -> join (onceFork x) == x \(x :: IO Int) -> (do a <- onceFork x; a; a) == xextra Create a new .extra%Perform some operation while holding 6. Will prevent all other operations from using the  while the action is ongoing.extraLike Y but will never block. If the operation cannot be executed immediately it will return u.extra Create a new  with a value.extraRead the current value of the .extra)Write a value to become the new value of .extra Modify a + producing a new value and a return result.extra Modify a , a restricted version of .extra.Perform some operation using the value in the , a restricted version of .extra Create a new .extra4Write a value into the Barrier, releasing anyone at +. Any subsequent attempts to signal the  will throw an exception.extra,Wait until a barrier has been signaled with .extra A version of  that never blocks, returning u- if the barrier has not yet been signaled.N% SafeextraList the files and directories directly within a directory. Each result will be prefixed by the query directory, and the special directories . and ..9 will be ignored. Intended as a cleaned up version of . withTempDir $ \dir -> do writeFile (dir </> "test.txt") ""; (== [dir </> "test.txt"]) <$> listContents dir let touch = mapM_ $ \x -> createDirectoryIfMissing True (takeDirectory x) >> writeFile x "" let listTest op as bs = withTempDir $ \dir -> do touch $ map (dir </>) as; res <- op dir; return $ map (drop (length dir + 1)) res == bs listTest listContents ["bar.txt","foo/baz.txt","zoo"] ["bar.txt","foo","zoo"]extraLike |, but only returns the directories in a directory, not the files. Each directory will be prefixed by the query directory. @listTest listDirectories ["bar.txt","foo/baz.txt","zoo"] ["foo"]extraLike y, but only returns the files in a directory, not other directories. Each file will be prefixed by the query directory. DlistTest listFiles ["bar.txt","foo/baz.txt","zoo"] ["bar.txt","zoo"]extraLike , but goes recursively through all subdirectories. This function will follow symlinks, and if they form a loop, this function will not terminate. glistTest listFilesRecursive ["bar.txt","zoo","foo" </> "baz.txt"] ["bar.txt","zoo","foo" </> "baz.txt"]extraLike _, but with a predicate to decide where to recurse into. Typically directories starting with .V would be ignored. The initial argument directory will have the test applied to it. listTest (listFilesInside $ return . not . isPrefixOf "." . takeFileName) ["bar.txt","foo" </> "baz.txt",".foo" </> "baz2.txt", "zoo"] ["bar.txt","zoo","foo" </> "baz.txt"] listTest (listFilesInside $ const $ return False) ["bar.txt"] []extra|Create a directory with permissions so that only the current user can view it. On Windows this function is equivalent to .ISafeU      NoneXextraLike , but setting an encoding.extraLike , but with the encoding .extraLike , but for binary files.extraA strict version of .extraA strict version of . When the string is produced, the entire file will have been read into memory and the file handle will have been closed. Closing the file handle does not rely on the garbage collector. f\(filter isHexDigit -> s) -> fmap (== s) $ withTempFile $ \file -> do writeFile file s; readFile' fileextraA strict version of , see  for details.extraA strict version of , see  for details.extraA strict version of , see  for details.extra(Write a file with a particular encoding.extraWrite a file with the  encoding. W\s -> withTempFile $ \file -> do writeFileUTF8 file s; fmap (== s) $ readFileUTF8' fileextraWrite a binary file. i\(ASCIIString s) -> withTempFile $ \file -> do writeFileBinary file s; fmap (== s) $ readFileBinary' fileextra Capture the  and  of a computation. ,captureOutput (print 1) == return ("1\n",())extra Execute an action with a custom , a wrapper around .extranProvide a function to create a temporary file, and a way to delete a temporary file. Most users should use $ which combines these operations.extraLike ( but using a custom temporary directory.extraCreate a temporary file in the temporary directory. The file will be deleted after the action completes (provided the file is not still open). The  will not have any file extension, will exist, and will be zero bytes long. If you require a file with a specific name, use . withTempFile doesFileExist == return True (doesFileExist =<< withTempFile return) == return False withTempFile readFile' == return ""extraxProvide a function to create a temporary directory, and a way to delete a temporary directory. Most users should use $ which combines these operations.extraLike ( but using a custom temporary directory.extraCreate a temporary directory inside the system temporary directory. The directory will be deleted after the action completes. withTempDir doesDirectoryExist == return True (doesDirectoryExist =<< withTempDir return) == return False withTempDir listFiles == return []extraReturns `$ when both files have the same size.extraReturns `- when the contents of both files is the same.extraReturns `S if both files have the same content. Raises an error if either file is missing. fileEq "does_not_exist1" "does_not_exist2" == undefined fileEq "does_not_exist" "does_not_exist" == undefined withTempFile $ \f1 -> fileEq "does_not_exist" f1 == undefined withTempFile $ \f1 -> withTempFile $ \f2 -> fileEq f1 f2 withTempFile $ \f1 -> withTempFile $ \f2 -> writeFile f1 "a" >> writeFile f2 "a" >> fileEq f1 f2 withTempFile $ \f1 -> withTempFile $ \f2 -> writeFile f1 "a" >> writeFile f2 "b" >> notM (fileEq f1 f2)} !"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxySafemextraReturn ` on Windows and Z! otherwise. A runtime version of #ifdef minw32_HOST_OS. Equivalent to os == "mingw32", but: more efficient; doesn't require typing an easily mistypeable string; actually asks about your OS not a library; doesn't bake in 32bit assumptions that are already false. </rant> isWindows == (os == "mingw32")extraReturn ` on Mac OS X and Z otherwise.z{|}None,PYextra A version of ~% that also captures the output, both  and . Returns a pair of the  and the output.extra A version of ~ that throws an error if the  is not .extra A version of ~ that captures the output (both  and  ) and throws an error if the  is not .:~Safe2(extra.A type alias for seconds, which are stored as .extraSleep for a number of seconds. 3fmap (round . fst) (duration $ sleep 1) == return 1extra A version of  that takes ) and never overflows the bounds of an M. In addition, the bug that negative timeouts run for ever has been fixed. timeout (-3) (print 1) == return Nothing timeout 0.1 (print 1) == fmap Just (print 1) do (t, _) <- duration $ timeout 0.1 $ sleep 1000; print t; return $ t < 1 timeout 0.1 (sleep 2 >> print 1) == return NothingextranShow a number of seconds, typically a duration, in a suitable manner with reasonable precision for a human. showDuration 3.435 == "3.44s" showDuration 623.8 == "10m24s" showDuration 62003.8 == "17h13m" showDuration 1e8 == "27777h47m"extraCall once to start, then call repeatedly to get the elapsed time since the first call. The time is guaranteed to be monotonic. This function is robust to system time changes. Ado f <- offsetTime; xs <- replicateM 10 f; return $ xs == sort xsextraA synonym for .extra'Record how long a computation takes in . ;do (a,_) <- duration $ sleep 1; return $ a >= 1 && a <= 1.5None)  !"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcfghijklmnopqrstuvwxyz{|}~$rsonqptvxuwyz{|}~ighkjlm:;978<=>@?A0/1LMW6Z[\XYNOSTUV]*+,-.QRFGHacbCB^`_DE')(%&P4523KIJ f !"#Safe/) !"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHI&JKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~           !"#$%&'(I)*+,-./0123454678797:7;7<=>?@ABCBDBEBFBGBHBIBJBKBLBMBNBOBPBQBRBSBTBUBVBWBXBY=Z=[=\=]=^_`_`abacadaefgfhijikiliminioipiqirisitiuiviwixiyizi{i|i}i~iiiiif4%?*+(4?43.*#$ ",+ ,/-?@4          4               ! ! " " # # $ $ % %&'()*++,,--..//001123456789:;<=>?@ABCDEFG H I J K L M N O P Q  4R?@STUVWUX?Y?@Z?[U\4]4^4_4`4a4b4cdeUfUgUhUiUjUkUlUmUnUoUpUqrstuvwx4y4z4{4|4}4~4444&&&&&&&&&&&& ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !                   ! " #$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwwxyz{z|z}z~?@?@#extra-1.6.15-G5dZ7hBrtynBqoUZQ0H6LRData.Either.ExtraControl.Exception.ExtraExtraData.IORef.ExtraData.List.NonEmpty.ExtraData.Tuple.Extra Numeric.ExtraData.List.ExtraData.Version.ExtraControl.Monad.ExtraControl.Concurrent.ExtraSystem.Directory.ExtraSystem.IO.ExtraSystem.Info.ExtraSystem.Process.ExtraSystem.Time.Extra Control.Arrow***&&&Data.Typeable.ExtraPartialSystem.Environment.ExtraSystem.TimeouttimeoutText.Read.Extrabase Data.Either fromRightfromLeftGHC.ErrerrorWithoutStackTracedirectory-1.3.3.0System.DirectorywithCurrentDirectory writeIORef'atomicWriteIORef'|>snoc|:appendlappendrsortOnunionunionBymaximum1minimum1 maximumBy1 minimumBy1 maximumOn1 minimumOn1firstseconddupebothfst3snd3thd3curry3uncurry3showDP intToDouble intToFloat floatToDouble doubleToFloat repeatedlyfordisjointanySameallSamenotNulllistunsnocconstakeEnddropEnd splitAtEndzipFrom zipWithFrom concatUnzip concatUnzip3 takeWhileEnd trimStarttrimEndtrimlowerupperword1line1 escapeHTML unescapeHTML escapeJSON unescapeJSONgroupOnnubOn maximumOn minimumOn groupSort groupSortOn groupSortBymergemergeByreplacebreakEndspanEndwordsBylinesBy firstJustdrop1 mconcatMapbreakOn breakOnEndsplitOnsplit dropWhileEnd' dropPrefix dropSuffix stripSuffix stripInfix stripInfixEndchunksOfnubSort nubSortOn nubSortBynubOrdnubOrdOnnubOrdBy $fShowColor$fShowRB readVersion fromLeft' fromRight' fromEither maybeToEither eitherToMaybemapLeftmapRightstringException showExceptionignoreerrorIOretry retryBoolcatch_ catchJust_handle_ handleJust_try_tryJust_ catchBool handleBooltryBoolwhenJust whenJustM whenMaybe whenMaybeMunitmaybeM fromMaybeMeitherMfold1Mfold1M_ partitionM concatMapM concatForM mconcatMapM mapMaybeMlooploopMwhileMwhenMunlessMifMnotM||^&&^anyMallMorMandMfindM firstJustMBarrierVarLockwithNumCapabilitiesonceonceForknewLockwithLock withLockTrynewVarreadVarwriteVar modifyVar modifyVar_withVar newBarrier signalBarrier waitBarrierwaitBarrierMaybe listContentslistDirectories listFileslistFilesRecursivelistFilesInsidecreateDirectoryPrivatereadFileEncoding readFileUTF8readFileBinary readFile'readFileEncoding' readFileUTF8'readFileBinary'writeFileEncoding writeFileUTF8writeFileBinary captureOutput withBuffering newTempFilenewTempFileWithin withTempFile newTempDirnewTempDirWithin withTempDirfileEq isWindowsisMac systemOutputsystem_ systemOutput_Secondssleep showDuration offsetTimeoffsetTimeIncreaseduration$fExceptionTimeout $fShowTimeout $fEqTimeout GHC.IORef writeIORef Data.IORefatomicWriteIORefatomicModifyIORef'atomicModifyIORef modifyIORef' modifyIORef mkWeakIORef readIORefnewIORefIORefData.List.NonEmptysortWithsortBy transposenubBynubunzipzipWithzip!! isPrefixOf groupAllWith1 groupWith1groupBy1group1 groupAllWith groupWithgroupBygroup partitionfilterbreakspan dropWhile takeWhilesplitAtdroptakerepeatreversecycleiterate interspersescanr1scanl1scanrscanlsome1inserttailsinitsmaptoListfromListsort<|initlasttailheadunfoldrunconsnonEmptyunfoldxorlengthGHC.BaseNonEmpty:| Data.TuplefstsndswapuncurrycurryData.Typeable.InternalTypeableghc-prim GHC.TypesTyCon Data.TypeabletypeOf7typeOf6typeOf5typeOf4typeOf3typeOf2typeOf1 rnfTypeReptypeRepFingerprint typeRepTyCon typeRepArgs splitTyConAppmkFunTy funResultTygcast2gcast1gcasteqTcast showsTypeReptypeReptypeOfTypeReprnfTyContyConFingerprint tyConName tyConModule tyConPackage Data.ProxyProxyData.Type.Equality:~:Refl:~~:HReflGHC.Real fromIntegral realToFrac GHC.FloatFloatingpiexplogsqrt**logBasesincostanasinacosatansinhcoshtanhasinhacoshatanhlog1pexpm1log1pexplog1mexpNumericshowOctshowHex showIntAtBase showHFloat showGFloatAlt showFFloatAlt showGFloat showFFloat showEFloatshowInt readSigned readFloatreadHexreadDecreadOctreadIntGHC.Read lexDigitsfromRat floatToDigits showFloat showSigned GHC.Classesnot Data.Foldablenull Data.Maybemaybe GHC.MaybeNothingGHC.Listconcatunzip3 Data.OldList Data.FunctiononmaximumminimumwordslinesJustfind concatMapMonoid dropWhileEndOrd++foldrfoldlfoldl'foldl1sumproductfoldr1elem Data.ListisSubsequenceOfData.Traversable mapAccumR mapAccumLnotElem minimumBy maximumByallanyorandunwordsunlines permutations subsequencesdeleteFirstsByunzip7unzip6unzip5unzip4zipWith7zipWith6zipWith5zipWith4zip7zip6zip5zip4genericReplicate genericIndexgenericSplitAt genericDrop genericTake genericLengthinsertBy intercalate intersectBy intersect\\deleteBydelete isInfixOf isSuffixOf findIndices findIndex elemIndices elemIndex stripPrefixzipWith3zip3lookup replicateiterate'scanl'foldl1' Data.VersionVersion makeVersion parseVersion showVersion versionBranch versionTagsLeftRightEitherMaybeisRightisLeftpartitionEithersrightsleftseitherIOfailGHC.IO.Exception IOException GHC.Exception ErrorCallGHC.IOcatchGHC.Exception.Type Exception SomeExceptionControl.Exception.Base catchJusthandle handleJusttrytryJustassertControl.ExceptionallowInterruptcatchesHandlerbracketOnErrorbracket_finallybracket onException mapExceptionPatternMatchFail RecSelError RecConError RecUpdError NoMethodError TypeErrorNonTerminationNestedAtomically GHC.Conc.SyncthrowToioErrorasyncExceptionFromExceptionasyncExceptionToExceptionBlockedIndefinitelyOnMVarBlockedIndefinitelyOnSTMDeadlockAllocationLimitExceededCompactionFailedAssertionFailedSomeAsyncExceptionAsyncException StackOverflow HeapOverflow ThreadKilled UserInterruptArrayExceptionIndexOutOfBoundsUndefinedElementevaluateuninterruptibleMaskuninterruptibleMask_maskmask_getMaskingState interruptiblethrowIO MaskingStateUnmaskedMaskedInterruptibleMaskedUninterruptiblethrowErrorCallWithLocation toException fromExceptiondisplayExceptionArithExceptionOverflow UnderflowLossOfPrecision DivideByZeroDenormalRatioZeroDenominatorwhenFalse fromMaybe Control.MonadfoldMmapMaybeunless||True&&guardjoinMonad>>=>>returnFunctorfmapmapMsequencemfilter<$!> replicateM_ replicateMfoldM_ zipWithM_zipWithM mapAndUnzipMforever<=<>=>filterMforMmsum sequence_forM_mapM_ Data.FunctorvoidapliftM5liftM4liftM3liftM2liftM=<< MonadPlusmzeromplusGHC.MVarMVarsetNumCapabilitiesControl.ConcurrentthreadWaitWriteSTMthreadWaitReadSTMthreadWaitWritethreadWaitReadrunInUnboundThreadrunInBoundThreadisCurrentThreadBoundforkOSWithUnmaskforkOS forkFinallyrtsSupportsBoundThreadsControl.Concurrent.ChanwriteList2ChangetChanContentsdupChanreadChan writeChannewChanChanControl.Concurrent.QSem signalQSemwaitQSemnewQSemQSemControl.Concurrent.QSemN signalQSemN waitQSemNnewQSemNQSemN GHC.Conc.IO threadDelayControl.Concurrent.MVar mkWeakMVaraddMVarFinalizermodifyMVarMaskedmodifyMVarMasked_ modifyMVar modifyMVar_withMVarMaskedwithMVarswapMVarmkWeakThreadIdthreadCapabilityyield myThreadId killThreadgetNumCapabilitiesforkOnWithUnmaskforkOnforkIOWithUnmaskforkIOThreadId isEmptyMVar tryReadMVar tryPutMVar tryTakeMVarputMVarreadMVartakeMVarnewMVar newEmptyMVargetDirectoryContentscreateDirectorygetTemporaryDirectorygetUserDocumentsDirectorygetAppUserDataDirectorygetXdgDirectoryListgetXdgDirectorygetHomeDirectorysetModificationTime setAccessTimegetModificationTime getAccessTimegetSymbolicLinkTargetisSymbolicLinkpathIsSymbolicLinkremoveDirectoryLinkcreateDirectoryLinkcreateFileLink doesFileExistdoesDirectoryExist doesPathExist getFileSizesetCurrentDirectorygetCurrentDirectory listDirectory exeExtension findFilesWith findFileWith findFilesfindFilefindExecutablesInDirectoriesfindExecutablesfindExecutablemakeRelativeToCurrentDirectory makeAbsolutecanonicalizePathcopyFileWithMetadatacopyFile renamePath renameFilerenameDirectory removeFileremovePathForciblyremoveDirectoryRecursiveremoveDirectorycreateDirectoryIfMissingcopyPermissionssetPermissionsgetPermissionssetOwnerSearchablesetOwnerExecutablesetOwnerWritablesetOwnerReadableemptyPermissions System.Directory.Internal.Common Permissionsreadablewritable executable searchable XdgDirectoryXdgData XdgConfigXdgCacheXdgDirectoryList XdgDataDirs XdgConfigDirsSystem.EnvironmentgetEnvironment withProgNamewithArgsunsetEnvsetEnv lookupEnvgetEnv getProgNamegetArgs!System.Environment.ExecutablePathgetExecutablePath System.IOreadFileGHC.IO.Encodingutf8 hGetContents'GHC.IO.Handle.Text hGetContentsGHC.IO.Handle.FDstdoutstderrGHC.IO.Handle.Types BufferMode GHC.IO.Handle hSetBufferingFilePathsameSize sameContentprintHandle(openBinaryTempFileWithDefaultPermissions"openTempFileWithDefaultPermissionsopenBinaryTempFile openTempFilefixIOwithBinaryFilewithFilehPrinthReadylocaleEncodingreadIOreadLn appendFile writeFileinteract getContentsgetLinegetCharputStrLnputStrputCharhShowhSetNewlineModehSetBinaryModehIsTerminalDevicehGetEchohSetEcho hIsSeekable hGetBuffering hIsWritable hIsReadable hIsClosedhIsOpenhTellhSeekhSetPosnhGetPosn hGetEncoding hSetEncoding hLookAheadisEOFhIsEOF hSetFileSize hFileSizehClose HandlePosnopenBinaryFileopenFilestdinhGetBufNonBlocking hGetBufSomehGetBufhPutBufNonBlockinghPutBuf hPutStrLnhPutStrhPutCharhGetLinehGetChar hWaitForInputmkTextEncodingchar8utf32beutf32leutf32utf16beutf16leutf16utf8_bomlatin1hFlushnoNewlineTranslationnativeNewlineModeuniversalNewlineMode nativeNewline NoBuffering LineBufferingBlockBufferingNewlineLFCRLF NewlineModeinputNLoutputNL GHC.IO.DeviceSeekMode AbsoluteSeek RelativeSeek SeekFromEndGHC.IO.Encoding.Types TextEncoding GHC.IO.IOModeIOModeReadMode WriteMode AppendMode ReadWriteMode System.Info compilerNamearchoscompilerVersionprocess-1.6.3.0System.ProcesssystemExitCode ExitSuccess rawSystemrunInteractiveProcessrunInteractiveCommand runProcess runCommandterminateProcessgetProcessExitCodewaitForProcessgetPidshowCommandForUserreadCreateProcessWithExitCodereadProcessWithExitCodereadCreateProcess readProcess callCommand callProcess spawnCommand spawnProcesscleanupProcesswithCreateProcess createProcessshellprocPidSystem.Process.InternalsinterruptProcessGroupOf createPipeFd createPipecreateProcess_System.Process.Common CreateProcesscmdspeccwdenvstd_instd_outstd_err close_fds create_group delegate_ctlcdetach_consolecreate_new_console new_session child_group child_useruse_process_jobsCmdSpec ShellCommand RawCommand StdStreamInherit UseHandle CreatePipeNoStream ProcessHandleDoubleIntRead readsPrecreadListreadPrec readListPrec Text.Readread readMaybe readEitherreadsparenslexPlexreadListPrecDefaultreadListDefault readParen Text.Read.LexLexemeCharSymbolStringNumberPuncIdentEOFText.ParserCombinators.ReadPrec readS_to_Prec readPrec_to_S readP_to_Prec readPrec_to_Pchoicepfail<+++++lookgetprecresetstepliftminPrecReadPrecPrecText.ParserCombinators.ReadPReadS