Copyright	© 2017 Herbert Valerio Riedel
License	GPLv3
Safe Haskell	Trustworthy
Language	Haskell2010

Data.TextMap.Unboxed.Lazy

Contents

Querying & lookup
Construction
Deconstruction
Traversals

Description

This module provides the TextMap container for storing maps of text keys to non-strict values.

This module is intended to be imported qualified, e.g.

import           Data.TextMap.Unboxed.Lazy (TextMap)
import qualified Data.TextMap.Unboxed.Lazy as TextMap

The API of this module provides value-lazy operations.

Synopsis

Documentation

data TextMap v Source #

A map of (unboxed) ShortText string keys to values.

The memory footprint of this data-structure is expressed in words

\[ 8 + 2n + \left\lceil \frac{1}{w} \sum_{i=0}^{n-1} len(k_i) \right\rceil + \sum_{i=0}^{n-1} size(v_i) \]

where

the word-size $w$ is either $w = 4$ or $w = 8$ bytes,
$len(k_i)$ denotes the UTF-8 size in bytes of the $i$-th key string, and
$size(v_i)$ denotes the allocated heap size of the $i$-th value in words.

NOTE: One word can be saved by unpacking TextMap (i.e. via {-# UNPACK #-}) into another constructor.

Instances

Functor TextMap Source #
Methods fmap :: (a -> b) -> TextMap a -> TextMap b # (<$) :: a -> TextMap b -> TextMap a #
Foldable TextMap Source #
Methods fold :: Monoid m => TextMap m -> m # foldMap :: Monoid m => (a -> m) -> TextMap a -> m # foldr :: (a -> b -> b) -> b -> TextMap a -> b # foldr' :: (a -> b -> b) -> b -> TextMap a -> b # foldl :: (b -> a -> b) -> b -> TextMap a -> b # foldl' :: (b -> a -> b) -> b -> TextMap a -> b # foldr1 :: (a -> a -> a) -> TextMap a -> a # foldl1 :: (a -> a -> a) -> TextMap a -> a # toList :: TextMap a -> [a] # null :: TextMap a -> Bool # length :: TextMap a -> Int # elem :: Eq a => a -> TextMap a -> Bool # maximum :: Ord a => TextMap a -> a # minimum :: Ord a => TextMap a -> a # sum :: Num a => TextMap a -> a # product :: Num a => TextMap a -> a #
Traversable TextMap Source #
Methods traverse :: Applicative f => (a -> f b) -> TextMap a -> f (TextMap b) # sequenceA :: Applicative f => TextMap (f a) -> f (TextMap a) # mapM :: Monad m => (a -> m b) -> TextMap a -> m (TextMap b) # sequence :: Monad m => TextMap (m a) -> m (TextMap a) #
IsList (TextMap v) Source #
Associated Types type Item (TextMap v) :: * # Methods fromList :: [Item (TextMap v)] -> TextMap v # fromListN :: Int -> [Item (TextMap v)] -> TextMap v # toList :: TextMap v -> [Item (TextMap v)] #
Eq v => Eq (TextMap v) Source #
Methods (==) :: TextMap v -> TextMap v -> Bool # (/=) :: TextMap v -> TextMap v -> Bool #
Ord v => Ord (TextMap v) Source #
Methods compare :: TextMap v -> TextMap v -> Ordering # (<) :: TextMap v -> TextMap v -> Bool # (<=) :: TextMap v -> TextMap v -> Bool # (>) :: TextMap v -> TextMap v -> Bool # (>=) :: TextMap v -> TextMap v -> Bool # max :: TextMap v -> TextMap v -> TextMap v # min :: TextMap v -> TextMap v -> TextMap v #
Read v => Read (TextMap v) Source #
Methods readsPrec :: Int -> ReadS (TextMap v) # readList :: ReadS [TextMap v] # readPrec :: ReadPrec (TextMap v) # readListPrec :: ReadPrec [TextMap v] #
Show v => Show (TextMap v) Source #
Methods showsPrec :: Int -> TextMap v -> ShowS # show :: TextMap v -> String # showList :: [TextMap v] -> ShowS #
NFData v => NFData (TextMap v) Source #
Methods rnf :: TextMap v -> () #
Hashable v => Hashable (TextMap v) Source #
Methods hashWithSalt :: Int -> TextMap v -> Int # hash :: TextMap v -> Int #
type Item (TextMap v) Source #
type Item (TextMap v) = (Key, v)

type Key = ShortText Source #

Querying & lookup

size :: TextMap v -> Int Source #

$\mathcal{O}(1)$. Report number of entries in map.

>>> size empty
0

>>> size (singleton "sa" LT)
1

>>> size (fromList [("a",True),("b",False),("a",False)])
2

null :: TextMap v -> Bool Source #

$\mathcal{O}(1)$. Test whether map is empty.

>>> null empty
True

>>> null (singleton "" ())
False

member :: Key -> TextMap v -> Bool Source #

$\mathcal{O}(\log n)$. Test whether key is present in map.

>>> member "empty" empty
False

>>> member "a" (fromList [("a",EQ),("b",GT),("c",LT)])
True

>>> member "d" (fromList [("a",EQ),("b",GT),("c",LT)])
False

lookup :: Key -> TextMap v -> Maybe v Source #

$\mathcal{O}(\log n)$. Lookup value for given key.

>>> lookup "a" (fromList [("bb",False),("cc",True)])
Nothing

>>> lookup "c" (fromList [("bb",False),("cc",True)])
Nothing

>>> lookup "cc" (fromList [("bb",False),("cc",True)])
Just True

>>> lookup "z" (fromList [("bb",False),("cc",True)])
Nothing

(!?) :: TextMap v -> Key -> Maybe v Source #

$\mathcal{O}(\log n)$. Lookup value for given key.

>>> fromList [("bb",False),("cc",True)] !? "cc"
Just True

This is a flipped infix alias of lookup.

findWithDefault :: v -> Key -> TextMap v -> v Source #

$\mathcal{O}(\log n)$. Lookup value for key in map or return default value if key not contained in map.

>>> findWithDefault True "z" (fromList [("bb",False),("cc",True)])
True

>>> findWithDefault True "bb" (fromList [("bb",False),("cc",True)])
False

Construction

empty :: TextMap v Source #

$\mathcal{O}(1)$. An empty TextMap.

singleton :: Key -> v -> TextMap v Source #

$\mathcal{O}(1)$. Construct map containing a single entry.

>>> toList (singleton "sa" LT)
[("sa",LT)]

fromList :: [(Key, v)] -> TextMap v Source #

$\mathcal{O}(n \log n)$. Construct map from list of key/value pairs.

>>> toList (fromList [("Hey",GT),("Jude",EQ),("Hey",LT),("Law",EQ),("Hey",EQ),("",EQ)])
[("",EQ),("Hey",EQ),("Jude",EQ),("Law",EQ)]

fromDistinctAscList :: [(Key, v)] -> TextMap v Source #

$\mathcal{O}(n)$. Construct map from list with distinct keys in ascending order.

NOTE: If the input list is not strictly ascending, an error is thrown.

fromMap :: Map Key v -> TextMap v Source #

$\mathcal{O}(n)$. Convert Map to TextMap.

Deconstruction

toList :: TextMap v -> [(Key, v)] Source #

$\mathcal{O}(n)$. list all key/value pairs of the map in ascending order of their keys.

>>> toList (fromList [("Hey",GT),("Jude",EQ),("Hey",LT),("Law",EQ),("Hey",EQ),("",EQ)])
[("",EQ),("Hey",EQ),("Jude",EQ),("Law",EQ)]

toMap :: TextMap v -> Map Key v Source #

$\mathcal{O}(n)$. Convert TextMap to Map.

Traversals

map :: (v -> w) -> TextMap v -> TextMap w Source #

$\mathcal{O}(n)$. Apply function to values in map.

>>> toList (map not (fromList [("a",True),("b",False),("a",False)]))
[("a",True),("b",True)]

This is a specialised version of fmap.