Map

Note: You should use Data.Map.Strict instead of this module if:

• You will eventually need all the values stored.
• The stored values don't represent large virtual data structures to be lazily computed.

An efficient implementation of ordered maps from keys to values (dictionaries). 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.

Bounds for union, intersection, and difference are as given by

• Guy Blelloch, Daniel Ferizovic, and Yihan Sun, "Just Join for Parallel Ordered Sets", https://arxiv.org/abs/1602.02120v3.

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. Warning: The size of the map must not exceed maxBound::Int. Violation of this condition is not detected and if the size limit is exceeded, its behaviour is undefined. 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. The Semigroup operation for Map is union, which prefers values from the left operand. If m1 maps a key k to a value a1, and m2 maps the same key to a different value a2, then their union m1 <> m2 maps k to a1.

Invariant preserving version of Map from the containers packages, suitable for use with Uniplate. Use toMap to construct values, and fromMap to deconstruct values.

Contains implementation of polymorphic type classes for data types Set and Map.

Strict Map. Import as:

import qualified RIO.Map as Map

This module does not export any partial or unchecked functions. For those, see RIO.Map.Partial and RIO.Map.Unchecked

Instances to convert between Map and association list. Copyright (C) 2009-2011 John Goerzen jgoerzen@complete.org All rights reserved. For license and copyright information, see the file LICENSE

Map type used to represent records and unions

A Map that remembers the original ordering of keys This is primarily used so that formatting preserves field order This is done primarily to avoid a dependency on insert-ordered-containers and also to improve performance

Hash-table, based on STM-specialized Hash Array Mapped Trie.

Type-level fmap for type-level functors. Note: this name clashes with Map from containers. FMap is provided as a synonym to avoid this.

Example

>>> data AddMul :: Nat -> Nat -> Exp Nat

>>> type instance Eval (AddMul x y) = (x TL.+ y) TL.* (x TL.+ y)

>>> :kind! Eval (Map (AddMul 2) '[0, 1, 2, 3, 4])
Eval (Map (AddMul 2) '[0, 1, 2, 3, 4]) :: [Nat]
= '[4, 9, 16, 25, 36]

A Map from keys k to values a.

Lists of pairs representing maps. The Listable tiers enumeration will not have repeated maps.

> take 6 (list :: [Map Nat Nat])
[Map [],Map [(0,0)],Map [(0,1)],Map [(1,0)],Map [(0,2)],Map [(1,1)]]

The abstract type of a Map. Its interface is a suitable subset of IntMap.