# Map -bytestring -base

An efficient implementation of ordered maps from keys to values (dictionaries). This module re-exports the value lazy Lazy API, plus several value strict functions from Strict. These modules are intended to be imported qualified, to avoid name clashes with Prelude functions, e.g. > import qualified Data.Map as Map The implementation of Map is based on size balanced binary trees (or trees of bounded balance) as described by: * Stephen Adams, "Efficient sets: a balancing act", Journal of Functional Programming 3(4):553-562, October 1993, http://www.swiss.ai.mit.edu/~adams/BB/. * J. Nievergelt and E.M. Reingold, "Binary search trees of bounded balance", SIAM journal of computing 2(1), March 1973. Note that the implementation is left-biased -- the elements of a first argument are always preferred to the second, for example in union or insert. Operation comments contain the operation time complexity in the Big-O notation (http://en.wikipedia.org/wiki/Big_O_notation).
A Map from keys k to values a.
O(n) map f t is the Text obtained by applying f to each element of t. Subject to fusion. Performs replacement on invalid scalar values.
O(n*min(n,W)). map f s is the set obtained by applying f to each element of s. It's worth noting that the size of the result may be smaller if, for some (x,y), x /= y && f x == f y
O(n). Map a function over all values in the map. > map (++ "x") (fromList [(5,"a"), (3,"b")]) == fromList [(3, "bx"), (5, "ax")]
O(n). Map a function over all values in the map. > map (++ "x") (fromList [(5,"a"), (3,"b")]) == fromList [(3, "bx"), (5, "ax")]
O(n*log n). map f s is the set obtained by applying f to each element of s. It's worth noting that the size of the result may be smaller if, for some (x,y), x /= y && f x == f y
O(n). The function mapAccum threads an accumulating argument through the map in ascending order of keys. > let f a b = (a ++ b, b ++ "X") > mapAccum f "Everything: " (fromList [(5,"a"), (3,"b")]) == ("Everything: ba", fromList [(3, "bX"), (5, "aX")])
O(n). The function mapAccum threads an accumulating argument through the map in ascending order of keys. > let f a b = (a ++ b, b ++ "X") > mapAccum f "Everything: " (fromList [(5,"a"), (3,"b")]) == ("Everything: ba", fromList [(3, "bX"), (5, "aX")])
O(n) Like a combination of map and foldl'. Applies a function to each element of a Text, passing an accumulating parameter from left to right, and returns a final Text. Performs replacement on invalid scalar values.
The mapAccumR function behaves like a combination of map and a strict foldr; it applies a function to each element of a Text, passing an accumulating parameter from right to left, and returning a final value of this accumulator together with the new Text. Performs replacement on invalid scalar values.
O(n). The function mapAccumR threads an accumulating argument through the map in descending order of keys.
O(n). The function mapAccumR threads an accumulating argument through the map in descending order of keys.
O(n). The function mapAccumWithKey threads an accumulating argument through the map in ascending order of keys. > let f a k b = (a ++ " " ++ (show k) ++ "-" ++ b, b ++ "X") > mapAccumWithKey f "Everything:" (fromList [(5,"a"), (3,"b")]) == ("Everything: 3-b 5-a", fromList [(3, "bX"), (5, "aX")])
O(n). The function mapAccumWithKey threads an accumulating argument through the map in ascending order of keys. > let f a k b = (a ++ " " ++ (show k) ++ "-" ++ b, b ++ "X") > mapAccumWithKey f "Everything:" (fromList [(5,"a"), (3,"b")]) == ("Everything: 3-b 5-a", fromList [(3, "bX"), (5, "aX")])
Constructs a new array derived from the original array by applying a function to each of the elements.