2 % (c) The AQUA Project, Glasgow University, 1994-1999
5 \section[Array]{Module @Array@}
8 {-# OPTIONS -fno-implicit-prelude #-}
13 module Ix -- export all of Ix
14 , Array -- Array type is abstract
16 , array -- :: (Ix a) => (a,a) -> [(a,b)] -> Array a b
17 , listArray -- :: (Ix a) => (a,a) -> [b] -> Array a b
18 , (!) -- :: (Ix a) => Array a b -> a -> b
19 , bounds -- :: (Ix a) => Array a b -> (a,a)
20 , indices -- :: (Ix a) => Array a b -> [a]
21 , elems -- :: (Ix a) => Array a b -> [b]
22 , assocs -- :: (Ix a) => Array a b -> [(a,b)]
23 , accumArray -- :: (Ix a) => (b -> c -> b) -> b -> (a,a) -> [(a,c)] -> Array a b
24 , (//) -- :: (Ix a) => Array a b -> [(a,b)] -> Array a b
25 , accum -- :: (Ix a) => (b -> c -> b) -> Array a b -> [(a,c)] -> Array a b
26 , ixmap -- :: (Ix a, Ix b) => (a,a) -> (a -> b) -> Array b c -> Array a b
30 -- Ix a => Functor (Array a)
31 -- (Ix a, Eq b) => Eq (Array a b)
32 -- (Ix a, Ord b) => Ord (Array a b)
33 -- (Ix a, Show a, Show b) => Show (Array a b)
34 -- (Ix a, Read a, Read b) => Read (Array a b)
37 -- Implementation checked wrt. Haskell 98 lib report, 1/99.
43 import PrelArr -- Most of the hard work is done here
51 %*********************************************************
53 \subsection{Definitions of array, !, bounds}
55 %*********************************************************
59 #ifdef USE_FOLDR_BUILD
60 {-# INLINE indices #-}
65 {-# SPECIALISE listArray :: (Int,Int) -> [b] -> Array Int b #-}
66 listArray :: (Ix a) => (a,a) -> [b] -> Array a b
67 listArray b vs = array b (zip (range b) vs)
69 {-# SPECIALISE indices :: Array Int b -> [Int] #-}
70 indices :: (Ix a) => Array a b -> [a]
71 indices = range . bounds
73 {-# SPECIALISE elems :: Array Int b -> [b] #-}
74 elems :: (Ix a) => Array a b -> [b]
75 elems a = [a!i | i <- indices a]
77 {-# SPECIALISE assocs :: Array Int b -> [(Int,b)] #-}
78 assocs :: (Ix a) => Array a b -> [(a,b)]
79 assocs a = [(i, a!i) | i <- indices a]
81 {-# SPECIALISE amap :: (b -> c) -> Array Int b -> Array Int c #-}
82 amap :: (Ix a) => (b -> c) -> Array a b -> Array a c
83 amap f a = array b [(i, f (a!i)) | i <- range b]
86 ixmap :: (Ix a, Ix b) => (a,a) -> (a -> b) -> Array b c -> Array a c
87 ixmap b f a = array b [(i, a ! f i) | i <- range b]
91 %*********************************************************
93 \subsection{Instance declarations for Array type}
95 %*********************************************************
98 instance Ix a => Functor (Array a) where
101 instance (Ix a, Eq b) => Eq (Array a b) where
102 a == a' = assocs a == assocs a'
103 a /= a' = assocs a /= assocs a'
105 instance (Ix a, Ord b) => Ord (Array a b) where
106 compare a b = compare (assocs a) (assocs b)
108 instance (Ix a, Show a, Show b) => Show (Array a b) where
109 showsPrec p a = showParen (p > 9) (
110 showString "array " .
111 shows (bounds a) . showChar ' ' .
113 showList = showList__ (showsPrec 0)
116 instance (Ix a, Read a, Read b) => Read (Array a b) where
117 readsPrec p = readParen (p > 9)
118 (\r -> [(array b as, u) | ("array",s) <- lex r,
121 readList = readList__ (readsPrec 0)