par -package:base -package:monad-par

Indicates that it may be beneficial to evaluate the first argument in parallel with the second. Returns the value of the second argument. a `par` b is exactly equivalent semantically to b. par is generally used when the value of a is likely to be required later, but not immediately. Also it is a good idea to ensure that a is not a trivial computation, otherwise the cost of spawning it in parallel overshadows the benefits obtained by running it in parallel. Note that actual parallelism is only supported by certain implementations (GHC with the -threaded option, and GPH, for now). On other implementations, par a b = b.

Execute two operations in parallel, based on parallel.

Spatial parallel composition of a signal function collection parameterized on the routing function.

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Unlifted par.

Parallel computation using all available cores. Same as ParOn []

O(n) The partition function takes a predicate a ByteString and returns the pair of ByteStrings with elements which do and do not satisfy the predicate, respectively; i.e.,

partition p bs == (filter p xs, filter (not . p) xs)

O(n) The partition function takes a predicate a ShortByteString and returns the pair of ShortByteStrings with elements which do and do not satisfy the predicate, respectively; i.e.,

partition p bs == (filter p sbs, filter (not . p) sbs)

O(n) The partition function takes a predicate and a Text, and returns the pair of Texts with elements which do and do not satisfy the predicate, respectively; i.e.

partition p t == (filter p t, filter (not . p) t)

Partition the map according to some predicate. The first map contains all elements that satisfy the predicate, the second all elements that fail the predicate. See also split.

partition (> "a") (fromList [(5,"a"), (3,"b")]) == (singleton 3 "b", singleton 5 "a")
partition (< "x") (fromList [(5,"a"), (3,"b")]) == (fromList [(3, "b"), (5, "a")], empty)
partition (> "x") (fromList [(5,"a"), (3,"b")]) == (empty, fromList [(3, "b"), (5, "a")])

Partition the map according to some predicate. The first map contains all elements that satisfy the predicate, the second all elements that fail the predicate. See also split.

partitionWithKey (\ k _ -> k > 3) (fromList [(5,"a"), (3,"b")]) == (singleton 5 "a", singleton 3 "b")
partitionWithKey (\ k _ -> k < 7) (fromList [(5,"a"), (3,"b")]) == (fromList [(3, "b"), (5, "a")], empty)
partitionWithKey (\ k _ -> k > 7) (fromList [(5,"a"), (3,"b")]) == (empty, fromList [(3, "b"), (5, "a")])

partition the set according to some predicate.

Partition the map according to a predicate. The first map contains all elements that satisfy the predicate, the second all elements that fail the predicate. See also split.

partition (> "a") (fromList [(5,"a"), (3,"b")]) == (singleton 3 "b", singleton 5 "a")
partition (< "x") (fromList [(5,"a"), (3,"b")]) == (fromList [(3, "b"), (5, "a")], empty)
partition (> "x") (fromList [(5,"a"), (3,"b")]) == (empty, fromList [(3, "b"), (5, "a")])

Partition the map according to a predicate. The first map contains all elements that satisfy the predicate, the second all elements that fail the predicate. See also split.

partitionWithKey (\ k _ -> k > 3) (fromList [(5,"a"), (3,"b")]) == (singleton 5 "a", singleton 3 "b")
partitionWithKey (\ k _ -> k < 7) (fromList [(5,"a"), (3,"b")]) == (fromList [(3, "b"), (5, "a")], empty)
partitionWithKey (\ k _ -> k > 7) (fromList [(5,"a"), (3,"b")]) == (empty, fromList [(3, "b"), (5, "a")])

The partition function takes a predicate p and a sequence xs and returns sequences of those elements which do and do not satisfy the predicate.

Partition the set into two sets, one with all elements that satisfy the predicate and one with all elements that don't satisfy the predicate. See also split.

Parses a time value given a format string. Missing information will be derived from 1970-01-01 00:00 UTC (which was a Thursday). Supports the same %-codes as formatTime, including %-, %_ and %0 modifiers, however padding widths are not supported. Case is not significant in the input string. Some variations in the input are accepted:

• %z %Ez accepts any of ±HHMM or ±HH:MM.
• %Z %EZ accepts any string of letters, or any of the formats accepted by %z.
• %0Y accepts exactly four digits.
• %0G accepts exactly four digits.
• %0C accepts exactly two digits.
• %0f accepts exactly two digits.

For example, to parse a date in YYYY-MM-DD format, while allowing the month and date to have optional leading zeros (notice the - modifier used for %m and %d):

Prelude Data.Time> parseTimeM True defaultTimeLocale "%Y-%-m-%-d" "2010-3-04" :: Maybe Day
Just 2010-03-04

Parses a time value given a list of pairs of format and input. Resulting value is constructed from all provided specifiers.

Parse a time value given a format string. Fails if the input could not be parsed using the given format. See parseTimeM for details.

Parse a value in either extended or basic format

Get the string corresponding to the given format specifier.

O(n) The partition function takes a predicate a ByteString and returns the pair of ByteStrings with elements which do and do not satisfy the predicate, respectively; i.e.,

partition p bs == (filter p sbs, filter (not . p) sbs)