1 -----------------------------------------------------------------------------
3 -- Module : Data.Array.Base
4 -- Copyright : (c) The University of Glasgow 2001
5 -- License : BSD-style (see the file libraries/base/LICENSE)
7 -- Maintainer : libraries@haskell.org
8 -- Stability : experimental
9 -- Portability : non-portable
11 -- Basis for IArray and MArray. Not intended for external consumption;
12 -- use IArray or MArray instead.
14 -----------------------------------------------------------------------------
17 module Data.Array.Base where
21 import Data.Ix ( Ix, range, index, rangeSize )
25 import Foreign.StablePtr
27 #ifdef __GLASGOW_HASKELL__
28 import GHC.Arr ( STArray, unsafeIndex )
29 import qualified GHC.Arr as Arr
30 import qualified GHC.Arr as ArrST
31 import GHC.ST ( ST(..), runST )
33 import GHC.Word ( Word(..) )
34 import GHC.Ptr ( Ptr(..), FunPtr(..), nullPtr, nullFunPtr )
35 import GHC.Float ( Float(..), Double(..) )
36 import GHC.Stable ( StablePtr(..) )
37 import GHC.Int ( Int8(..), Int16(..), Int32(..), Int64(..) )
38 import GHC.Word ( Word8(..), Word16(..), Word32(..), Word64(..) )
43 import Foreign.Storable
44 import qualified Hugs.Array as Arr
45 import qualified Hugs.ST as ArrST
46 import Hugs.Array ( unsafeIndex )
47 import Hugs.ST ( STArray, ST(..), runST )
56 -----------------------------------------------------------------------------
57 -- Class of immutable arrays
59 -- | Class of array types with immutable bounds
60 -- (even if the array elements are mutable).
61 class HasBounds a where
62 -- | Extracts the bounds of an array
63 bounds :: Ix i => a i e -> (i,i)
65 {- | Class of immutable array types.
67 An array type has the form @(a i e)@ where @a@ is the array type
68 constructor (kind @* -> * -> *@), @i@ is the index type (a member of
69 the class 'Ix'), and @e@ is the element type. The @IArray@ class is
70 parameterised over both @a@ and @e@, so that instances specialised to
71 certain element types can be defined.
73 class HasBounds a => IArray a e where
74 unsafeArray :: Ix i => (i,i) -> [(Int, e)] -> a i e
75 unsafeAt :: Ix i => a i e -> Int -> e
76 unsafeReplace :: Ix i => a i e -> [(Int, e)] -> a i e
77 unsafeAccum :: Ix i => (e -> e' -> e) -> a i e -> [(Int, e')] -> a i e
78 unsafeAccumArray :: Ix i => (e -> e' -> e) -> e -> (i,i) -> [(Int, e')] -> a i e
80 unsafeReplace arr ies = runST (unsafeReplaceST arr ies >>= unsafeFreeze)
81 unsafeAccum f arr ies = runST (unsafeAccumST f arr ies >>= unsafeFreeze)
82 unsafeAccumArray f e lu ies = runST (unsafeAccumArrayST f e lu ies >>= unsafeFreeze)
84 {-# INLINE unsafeReplaceST #-}
85 unsafeReplaceST :: (IArray a e, Ix i) => a i e -> [(Int, e)] -> ST s (STArray s i e)
86 unsafeReplaceST arr ies = do
88 sequence_ [unsafeWrite marr i e | (i, e) <- ies]
91 {-# INLINE unsafeAccumST #-}
92 unsafeAccumST :: (IArray a e, Ix i) => (e -> e' -> e) -> a i e -> [(Int, e')] -> ST s (STArray s i e)
93 unsafeAccumST f arr ies = do
96 old <- unsafeRead marr i
97 unsafeWrite marr i (f old new)
101 {-# INLINE unsafeAccumArrayST #-}
102 unsafeAccumArrayST :: Ix i => (e -> e' -> e) -> e -> (i,i) -> [(Int, e')] -> ST s (STArray s i e)
103 unsafeAccumArrayST f e (l,u) ies = do
104 marr <- newArray (l,u) e
106 old <- unsafeRead marr i
107 unsafeWrite marr i (f old new)
114 {-| Constructs an immutable array from a pair of bounds and a list of
115 initial associations.
117 The bounds are specified as a pair of the lowest and highest bounds in
118 the array respectively. For example, a one-origin vector of length 10
119 has bounds (1,10), and a one-origin 10 by 10 matrix has bounds
122 An association is a pair of the form @(i,x)@, which defines the value of
123 the array at index @i@ to be @x@. The array is undefined if any index
124 in the list is out of bounds. If any two associations in the list have
125 the same index, the value at that index is implementation-dependent.
126 (In GHC, the last value specified for that index is used.
127 Other implementations will also do this for unboxed arrays, but Haskell
128 98 requires that for 'Array' the value at such indices is bottom.)
130 Because the indices must be checked for these errors, 'array' is
131 strict in the bounds argument and in the indices of the association
132 list. Whether @array@ is strict or non-strict in the elements depends
133 on the array type: 'Data.Array.Array' is a non-strict array type, but
134 all of the 'Data.Array.Unboxed.UArray' arrays are strict. Thus in a
135 non-strict array, recurrences such as the following are possible:
137 > a = array (1,100) ((1,1) : [(i, i * a!(i-1)) | i \<- [2..100]])
139 Not every index within the bounds of the array need appear in the
140 association list, but the values associated with indices that do not
141 appear will be undefined.
143 If, in any dimension, the lower bound is greater than the upper bound,
144 then the array is legal, but empty. Indexing an empty array always
145 gives an array-bounds error, but 'bounds' still yields the bounds with
146 which the array was constructed.
148 array :: (IArray a e, Ix i)
149 => (i,i) -- ^ bounds of the array: (lowest,highest)
150 -> [(i, e)] -- ^ list of associations
152 array (l,u) ies = unsafeArray (l,u) [(index (l,u) i, e) | (i, e) <- ies]
154 -- Since unsafeFreeze is not guaranteed to be only a cast, we will
155 -- use unsafeArray and zip instead of a specialized loop to implement
156 -- listArray, unlike Array.listArray, even though it generates some
157 -- unnecessary heap allocation. Will use the loop only when we have
158 -- fast unsafeFreeze, namely for Array and UArray (well, they cover
159 -- almost all cases).
161 {-# INLINE listArray #-}
163 -- | Constructs an immutable array from a list of initial elements.
164 -- The list gives the elements of the array in ascending order
165 -- beginning with the lowest index.
166 listArray :: (IArray a e, Ix i) => (i,i) -> [e] -> a i e
167 listArray (l,u) es = unsafeArray (l,u) (zip [0 .. rangeSize (l,u) - 1] es)
169 {-# INLINE listArrayST #-}
170 listArrayST :: Ix i => (i,i) -> [e] -> ST s (STArray s i e)
171 listArrayST (l,u) es = do
172 marr <- newArray_ (l,u)
173 let n = rangeSize (l,u)
174 let fillFromList i xs | i == n = return ()
175 | otherwise = case xs of
177 y:ys -> unsafeWrite marr i y >> fillFromList (i+1) ys
182 "listArray/Array" listArray =
183 \lu es -> runST (listArrayST lu es >>= ArrST.unsafeFreezeSTArray)
186 {-# INLINE listUArrayST #-}
187 listUArrayST :: (MArray (STUArray s) e (ST s), Ix i)
188 => (i,i) -> [e] -> ST s (STUArray s i e)
189 listUArrayST (l,u) es = do
190 marr <- newArray_ (l,u)
191 let n = rangeSize (l,u)
192 let fillFromList i xs | i == n = return ()
193 | otherwise = case xs of
195 y:ys -> unsafeWrite marr i y >> fillFromList (i+1) ys
199 -- I don't know how to write a single rule for listUArrayST, because
200 -- the type looks like constrained over 's', which runST doesn't
201 -- like. In fact all MArray (STUArray s) instances are polymorphic
202 -- wrt. 's', but runST can't know that.
204 -- I would like to write a rule for listUArrayST (or listArray or
205 -- whatever) applied to unpackCString#. Unfortunately unpackCString#
206 -- calls seem to be floated out, then floated back into the middle
207 -- of listUArrayST, so I was not able to do this.
210 "listArray/UArray/Bool" listArray = \lu (es :: [Bool]) ->
211 runST (listUArrayST lu es >>= unsafeFreezeSTUArray)
212 "listArray/UArray/Char" listArray = \lu (es :: [Char]) ->
213 runST (listUArrayST lu es >>= unsafeFreezeSTUArray)
214 "listArray/UArray/Int" listArray = \lu (es :: [Int]) ->
215 runST (listUArrayST lu es >>= unsafeFreezeSTUArray)
216 "listArray/UArray/Word" listArray = \lu (es :: [Word]) ->
217 runST (listUArrayST lu es >>= unsafeFreezeSTUArray)
218 "listArray/UArray/Ptr" listArray = \lu (es :: [Ptr a]) ->
219 runST (listUArrayST lu es >>= unsafeFreezeSTUArray)
220 "listArray/UArray/FunPtr" listArray = \lu (es :: [FunPtr a]) ->
221 runST (listUArrayST lu es >>= unsafeFreezeSTUArray)
222 "listArray/UArray/Float" listArray = \lu (es :: [Float]) ->
223 runST (listUArrayST lu es >>= unsafeFreezeSTUArray)
224 "listArray/UArray/Double" listArray = \lu (es :: [Double]) ->
225 runST (listUArrayST lu es >>= unsafeFreezeSTUArray)
226 "listArray/UArray/StablePtr" listArray = \lu (es :: [StablePtr a]) ->
227 runST (listUArrayST lu es >>= unsafeFreezeSTUArray)
228 "listArray/UArray/Int8" listArray = \lu (es :: [Int8]) ->
229 runST (listUArrayST lu es >>= unsafeFreezeSTUArray)
230 "listArray/UArray/Int16" listArray = \lu (es :: [Int16]) ->
231 runST (listUArrayST lu es >>= unsafeFreezeSTUArray)
232 "listArray/UArray/Int32" listArray = \lu (es :: [Int32]) ->
233 runST (listUArrayST lu es >>= unsafeFreezeSTUArray)
234 "listArray/UArray/Int64" listArray = \lu (es :: [Int64]) ->
235 runST (listUArrayST lu es >>= unsafeFreezeSTUArray)
236 "listArray/UArray/Word8" listArray = \lu (es :: [Word8]) ->
237 runST (listUArrayST lu es >>= unsafeFreezeSTUArray)
238 "listArray/UArray/Word16" listArray = \lu (es :: [Word16]) ->
239 runST (listUArrayST lu es >>= unsafeFreezeSTUArray)
240 "listArray/UArray/Word32" listArray = \lu (es :: [Word32]) ->
241 runST (listUArrayST lu es >>= unsafeFreezeSTUArray)
242 "listArray/UArray/Word64" listArray = \lu (es :: [Word64]) ->
243 runST (listUArrayST lu es >>= unsafeFreezeSTUArray)
247 -- | Returns the element of an immutable array at the specified index.
248 (!) :: (IArray a e, Ix i) => a i e -> i -> e
249 arr ! i = case bounds arr of (l,u) -> unsafeAt arr (index (l,u) i)
251 {-# INLINE indices #-}
252 -- | Returns a list of all the valid indices in an array.
253 indices :: (HasBounds a, Ix i) => a i e -> [i]
254 indices arr = case bounds arr of (l,u) -> range (l,u)
257 -- | Returns a list of all the elements of an array, in the same order
259 elems :: (IArray a e, Ix i) => a i e -> [e]
260 elems arr = case bounds arr of
261 (l,u) -> [unsafeAt arr i | i <- [0 .. rangeSize (l,u) - 1]]
263 {-# INLINE assocs #-}
264 -- | Returns the contents of an array as a list of associations.
265 assocs :: (IArray a e, Ix i) => a i e -> [(i, e)]
266 assocs arr = case bounds arr of
267 (l,u) -> [(i, unsafeAt arr (unsafeIndex (l,u) i)) | i <- range (l,u)]
269 {-# INLINE accumArray #-}
272 Constructs an immutable array from a list of associations. Unlike
273 'array', the same index is allowed to occur multiple times in the list
274 of associations; an /accumulating function/ is used to combine the
275 values of elements with the same index.
277 For example, given a list of values of some index type, hist produces
278 a histogram of the number of occurrences of each index within a
281 > hist :: (Ix a, Num b) => (a,a) -> [a] -> Array a b
282 > hist bnds is = accumArray (+) 0 bnds [(i, 1) | i\<-is, inRange bnds i]
284 accumArray :: (IArray a e, Ix i)
285 => (e -> e' -> e) -- ^ An accumulating function
286 -> e -- ^ A default element
287 -> (i,i) -- ^ The bounds of the array
288 -> [(i, e')] -- ^ List of associations
289 -> a i e -- ^ Returns: the array
290 accumArray f init (l,u) ies =
291 unsafeAccumArray f init (l,u) [(index (l,u) i, e) | (i, e) <- ies]
295 Takes an array and a list of pairs and returns an array identical to
296 the left argument except that it has been updated by the associations
297 in the right argument. For example, if m is a 1-origin, n by n matrix,
298 then @m\/\/[((i,i), 0) | i \<- [1..n]]@ is the same matrix, except with
301 As with the 'array' function, if any two associations in the list have
302 the same index, the value at that index is implementation-dependent.
303 (In GHC, the last value specified for that index is used.
304 Other implementations will also do this for unboxed arrays, but Haskell
305 98 requires that for 'Array' the value at such indices is bottom.)
307 For most array types, this operation is O(/n/) where /n/ is the size
308 of the array. However, the 'Data.Array.Diff.DiffArray' type provides
309 this operation with complexity linear in the number of updates.
311 (//) :: (IArray a e, Ix i) => a i e -> [(i, e)] -> a i e
312 arr // ies = case bounds arr of
313 (l,u) -> unsafeReplace arr [(index (l,u) i, e) | (i, e) <- ies]
317 @accum f@ takes an array and an association list and accumulates pairs
318 from the list into the array with the accumulating function @f@. Thus
319 'accumArray' can be defined using 'accum':
321 > accumArray f z b = accum f (array b [(i, z) | i \<- range b])
323 accum :: (IArray a e, Ix i) => (e -> e' -> e) -> a i e -> [(i, e')] -> a i e
324 accum f arr ies = case bounds arr of
325 (l,u) -> unsafeAccum f arr [(index (l,u) i, e) | (i, e) <- ies]
328 -- | Returns a new array derived from the original array by applying a
329 -- function to each of the elements.
330 amap :: (IArray a e', IArray a e, Ix i) => (e' -> e) -> a i e' -> a i e
331 amap f arr = case bounds arr of
332 (l,u) -> unsafeArray (l,u) [(i, f (unsafeAt arr i)) |
333 i <- [0 .. rangeSize (l,u) - 1]]
335 -- | Returns a new array derived from the original array by applying a
336 -- function to each of the indices.
337 ixmap :: (IArray a e, Ix i, Ix j) => (i,i) -> (i -> j) -> a j e -> a i e
339 unsafeArray (l,u) [(unsafeIndex (l,u) i, arr ! f i) | i <- range (l,u)]
341 -----------------------------------------------------------------------------
342 -- Normal polymorphic arrays
344 instance HasBounds Arr.Array where
345 {-# INLINE bounds #-}
348 instance IArray Arr.Array e where
349 {-# INLINE unsafeArray #-}
350 unsafeArray = Arr.unsafeArray
351 {-# INLINE unsafeAt #-}
352 unsafeAt = Arr.unsafeAt
353 {-# INLINE unsafeReplace #-}
354 unsafeReplace = Arr.unsafeReplace
355 {-# INLINE unsafeAccum #-}
356 unsafeAccum = Arr.unsafeAccum
357 {-# INLINE unsafeAccumArray #-}
358 unsafeAccumArray = Arr.unsafeAccumArray
360 -----------------------------------------------------------------------------
361 -- Flat unboxed arrays
363 -- | Arrays with unboxed elements. Instances of 'IArray' are provided
364 -- for 'UArray' with certain element types ('Int', 'Float', 'Char',
365 -- etc.; see the 'UArray' class for a full list).
367 -- A 'UArray' will generally be more efficient (in terms of both time
368 -- and space) than the equivalent 'Data.Array.Array' with the same
369 -- element type. However, 'UArray' is strict in its elements - so
370 -- don\'t use 'UArray' if you require the non-strictness that
371 -- 'Data.Array.Array' provides.
373 -- Because the @IArray@ interface provides operations overloaded on
374 -- the type of the array, it should be possible to just change the
375 -- array type being used by a program from say @Array@ to @UArray@ to
376 -- get the benefits of unboxed arrays (don\'t forget to import
377 -- "Data.Array.Unboxed" instead of "Data.Array").
379 #ifdef __GLASGOW_HASKELL__
380 data UArray i e = UArray !i !i ByteArray#
383 data UArray i e = UArray !i !i !ByteArray
386 INSTANCE_TYPEABLE2(UArray,uArrayTc,"UArray")
388 instance HasBounds UArray where
389 {-# INLINE bounds #-}
390 bounds (UArray l u _) = (l,u)
392 {-# INLINE unsafeArrayUArray #-}
393 unsafeArrayUArray :: (MArray (STUArray s) e (ST s), Ix i)
394 => (i,i) -> [(Int, e)] -> e -> ST s (UArray i e)
395 unsafeArrayUArray (l,u) ies default_elem = do
396 marr <- newArray (l,u) default_elem
397 sequence_ [unsafeWrite marr i e | (i, e) <- ies]
398 unsafeFreezeSTUArray marr
400 #ifdef __GLASGOW_HASKELL__
401 {-# INLINE unsafeFreezeSTUArray #-}
402 unsafeFreezeSTUArray :: STUArray s i e -> ST s (UArray i e)
403 unsafeFreezeSTUArray (STUArray l u marr#) = ST $ \s1# ->
404 case unsafeFreezeByteArray# marr# s1# of { (# s2#, arr# #) ->
405 (# s2#, UArray l u arr# #) }
409 unsafeFreezeSTUArray :: STUArray s i e -> ST s (UArray i e)
410 unsafeFreezeSTUArray (STUArray l u marr) = do
411 arr <- unsafeFreezeMutableByteArray marr
412 return (UArray l u arr)
415 {-# INLINE unsafeReplaceUArray #-}
416 unsafeReplaceUArray :: (MArray (STUArray s) e (ST s), Ix i)
417 => UArray i e -> [(Int, e)] -> ST s (UArray i e)
418 unsafeReplaceUArray arr ies = do
419 marr <- thawSTUArray arr
420 sequence_ [unsafeWrite marr i e | (i, e) <- ies]
421 unsafeFreezeSTUArray marr
423 {-# INLINE unsafeAccumUArray #-}
424 unsafeAccumUArray :: (MArray (STUArray s) e (ST s), Ix i)
425 => (e -> e' -> e) -> UArray i e -> [(Int, e')] -> ST s (UArray i e)
426 unsafeAccumUArray f arr ies = do
427 marr <- thawSTUArray arr
429 old <- unsafeRead marr i
430 unsafeWrite marr i (f old new)
432 unsafeFreezeSTUArray marr
434 {-# INLINE unsafeAccumArrayUArray #-}
435 unsafeAccumArrayUArray :: (MArray (STUArray s) e (ST s), Ix i)
436 => (e -> e' -> e) -> e -> (i,i) -> [(Int, e')] -> ST s (UArray i e)
437 unsafeAccumArrayUArray f init (l,u) ies = do
438 marr <- newArray (l,u) init
440 old <- unsafeRead marr i
441 unsafeWrite marr i (f old new)
443 unsafeFreezeSTUArray marr
445 {-# INLINE eqUArray #-}
446 eqUArray :: (IArray UArray e, Ix i, Eq e) => UArray i e -> UArray i e -> Bool
447 eqUArray arr1@(UArray l1 u1 _) arr2@(UArray l2 u2 _) =
448 if rangeSize (l1,u1) == 0 then rangeSize (l2,u2) == 0 else
449 l1 == l2 && u1 == u2 &&
450 and [unsafeAt arr1 i == unsafeAt arr2 i | i <- [0 .. rangeSize (l1,u1) - 1]]
452 {-# INLINE cmpUArray #-}
453 cmpUArray :: (IArray UArray e, Ix i, Ord e) => UArray i e -> UArray i e -> Ordering
454 cmpUArray arr1 arr2 = compare (assocs arr1) (assocs arr2)
456 {-# INLINE cmpIntUArray #-}
457 cmpIntUArray :: (IArray UArray e, Ord e) => UArray Int e -> UArray Int e -> Ordering
458 cmpIntUArray arr1@(UArray l1 u1 _) arr2@(UArray l2 u2 _) =
459 if rangeSize (l1,u1) == 0 then if rangeSize (l2,u2) == 0 then EQ else LT else
460 if rangeSize (l2,u2) == 0 then GT else
461 case compare l1 l2 of
462 EQ -> foldr cmp (compare u1 u2) [0 .. rangeSize (l1, min u1 u2) - 1]
465 cmp i rest = case compare (unsafeAt arr1 i) (unsafeAt arr2 i) of
469 {-# RULES "cmpUArray/Int" cmpUArray = cmpIntUArray #-}
471 -----------------------------------------------------------------------------
475 showsIArray :: (IArray UArray e, Ix i, Show i, Show e) =>
476 Int -> UArray i e -> ShowS
479 showsIArray :: (IArray a e, Ix i, Show i, Show e) => Int -> a i e -> ShowS
482 showString "array " .
487 -----------------------------------------------------------------------------
488 -- Flat unboxed arrays: instances
491 unsafeAtBArray :: Storable e => UArray i e -> Int -> e
492 unsafeAtBArray (UArray _ _ arr) = readByteArray arr
495 instance IArray UArray Bool where
496 {-# INLINE unsafeArray #-}
497 unsafeArray lu ies = runST (unsafeArrayUArray lu ies False)
498 #ifdef __GLASGOW_HASKELL__
499 {-# INLINE unsafeAt #-}
500 unsafeAt (UArray _ _ arr#) (I# i#) =
501 (indexWordArray# arr# (bOOL_INDEX i#) `and#` bOOL_BIT i#)
502 `neWord#` int2Word# 0#
505 unsafeAt (UArray _ _ arr) i =
506 testBit (readByteArray arr (bOOL_INDEX i)::BitSet) (bOOL_SUBINDEX i)
508 {-# INLINE unsafeReplace #-}
509 unsafeReplace arr ies = runST (unsafeReplaceUArray arr ies)
510 {-# INLINE unsafeAccum #-}
511 unsafeAccum f arr ies = runST (unsafeAccumUArray f arr ies)
512 {-# INLINE unsafeAccumArray #-}
513 unsafeAccumArray f init lu ies = runST (unsafeAccumArrayUArray f init lu ies)
515 instance IArray UArray Char where
516 {-# INLINE unsafeArray #-}
517 unsafeArray lu ies = runST (unsafeArrayUArray lu ies '\0')
518 {-# INLINE unsafeAt #-}
519 #ifdef __GLASGOW_HASKELL__
520 unsafeAt (UArray _ _ arr#) (I# i#) = C# (indexWideCharArray# arr# i#)
523 unsafeAt = unsafeAtBArray
525 {-# INLINE unsafeReplace #-}
526 unsafeReplace arr ies = runST (unsafeReplaceUArray arr ies)
527 {-# INLINE unsafeAccum #-}
528 unsafeAccum f arr ies = runST (unsafeAccumUArray f arr ies)
529 {-# INLINE unsafeAccumArray #-}
530 unsafeAccumArray f init lu ies = runST (unsafeAccumArrayUArray f init lu ies)
532 instance IArray UArray Int where
533 {-# INLINE unsafeArray #-}
534 unsafeArray lu ies = runST (unsafeArrayUArray lu ies 0)
535 #ifdef __GLASGOW_HASKELL__
536 {-# INLINE unsafeAt #-}
537 unsafeAt (UArray _ _ arr#) (I# i#) = I# (indexIntArray# arr# i#)
540 unsafeAt = unsafeAtBArray
542 {-# INLINE unsafeReplace #-}
543 unsafeReplace arr ies = runST (unsafeReplaceUArray arr ies)
544 {-# INLINE unsafeAccum #-}
545 unsafeAccum f arr ies = runST (unsafeAccumUArray f arr ies)
546 {-# INLINE unsafeAccumArray #-}
547 unsafeAccumArray f init lu ies = runST (unsafeAccumArrayUArray f init lu ies)
549 instance IArray UArray Word where
550 {-# INLINE unsafeArray #-}
551 unsafeArray lu ies = runST (unsafeArrayUArray lu ies 0)
552 #ifdef __GLASGOW_HASKELL__
553 {-# INLINE unsafeAt #-}
554 unsafeAt (UArray _ _ arr#) (I# i#) = W# (indexWordArray# arr# i#)
557 unsafeAt = unsafeAtBArray
559 {-# INLINE unsafeReplace #-}
560 unsafeReplace arr ies = runST (unsafeReplaceUArray arr ies)
561 {-# INLINE unsafeAccum #-}
562 unsafeAccum f arr ies = runST (unsafeAccumUArray f arr ies)
563 {-# INLINE unsafeAccumArray #-}
564 unsafeAccumArray f init lu ies = runST (unsafeAccumArrayUArray f init lu ies)
566 instance IArray UArray (Ptr a) where
567 {-# INLINE unsafeArray #-}
568 unsafeArray lu ies = runST (unsafeArrayUArray lu ies nullPtr)
569 {-# INLINE unsafeAt #-}
570 #ifdef __GLASGOW_HASKELL__
571 unsafeAt (UArray _ _ arr#) (I# i#) = Ptr (indexAddrArray# arr# i#)
574 unsafeAt = unsafeAtBArray
576 {-# INLINE unsafeReplace #-}
577 unsafeReplace arr ies = runST (unsafeReplaceUArray arr ies)
578 {-# INLINE unsafeAccum #-}
579 unsafeAccum f arr ies = runST (unsafeAccumUArray f arr ies)
580 {-# INLINE unsafeAccumArray #-}
581 unsafeAccumArray f init lu ies = runST (unsafeAccumArrayUArray f init lu ies)
583 instance IArray UArray (FunPtr a) where
584 {-# INLINE unsafeArray #-}
585 unsafeArray lu ies = runST (unsafeArrayUArray lu ies nullFunPtr)
586 #ifdef __GLASGOW_HASKELL__
587 {-# INLINE unsafeAt #-}
588 unsafeAt (UArray _ _ arr#) (I# i#) = FunPtr (indexAddrArray# arr# i#)
591 unsafeAt = unsafeAtBArray
593 {-# INLINE unsafeReplace #-}
594 unsafeReplace arr ies = runST (unsafeReplaceUArray arr ies)
595 {-# INLINE unsafeAccum #-}
596 unsafeAccum f arr ies = runST (unsafeAccumUArray f arr ies)
597 {-# INLINE unsafeAccumArray #-}
598 unsafeAccumArray f init lu ies = runST (unsafeAccumArrayUArray f init lu ies)
600 instance IArray UArray Float where
601 {-# INLINE unsafeArray #-}
602 unsafeArray lu ies = runST (unsafeArrayUArray lu ies 0)
603 #ifdef __GLASGOW_HASKELL__
604 {-# INLINE unsafeAt #-}
605 unsafeAt (UArray _ _ arr#) (I# i#) = F# (indexFloatArray# arr# i#)
608 unsafeAt = unsafeAtBArray
610 {-# INLINE unsafeReplace #-}
611 unsafeReplace arr ies = runST (unsafeReplaceUArray arr ies)
612 {-# INLINE unsafeAccum #-}
613 unsafeAccum f arr ies = runST (unsafeAccumUArray f arr ies)
614 {-# INLINE unsafeAccumArray #-}
615 unsafeAccumArray f init lu ies = runST (unsafeAccumArrayUArray f init lu ies)
617 instance IArray UArray Double where
618 {-# INLINE unsafeArray #-}
619 unsafeArray lu ies = runST (unsafeArrayUArray lu ies 0)
620 #ifdef __GLASGOW_HASKELL__
621 {-# INLINE unsafeAt #-}
622 unsafeAt (UArray _ _ arr#) (I# i#) = D# (indexDoubleArray# arr# i#)
625 unsafeAt = unsafeAtBArray
627 {-# INLINE unsafeReplace #-}
628 unsafeReplace arr ies = runST (unsafeReplaceUArray arr ies)
629 {-# INLINE unsafeAccum #-}
630 unsafeAccum f arr ies = runST (unsafeAccumUArray f arr ies)
631 {-# INLINE unsafeAccumArray #-}
632 unsafeAccumArray f init lu ies = runST (unsafeAccumArrayUArray f init lu ies)
634 instance IArray UArray (StablePtr a) where
635 {-# INLINE unsafeArray #-}
636 unsafeArray lu ies = runST (unsafeArrayUArray lu ies nullStablePtr)
637 #ifdef __GLASGOW_HASKELL__
638 {-# INLINE unsafeAt #-}
639 unsafeAt (UArray _ _ arr#) (I# i#) = StablePtr (indexStablePtrArray# arr# i#)
642 unsafeAt = unsafeAtBArray
644 {-# INLINE unsafeReplace #-}
645 unsafeReplace arr ies = runST (unsafeReplaceUArray arr ies)
646 {-# INLINE unsafeAccum #-}
647 unsafeAccum f arr ies = runST (unsafeAccumUArray f arr ies)
648 {-# INLINE unsafeAccumArray #-}
649 unsafeAccumArray f init lu ies = runST (unsafeAccumArrayUArray f init lu ies)
651 -- bogus StablePtr value for initialising a UArray of StablePtr.
652 #ifdef __GLASGOW_HASKELL__
653 nullStablePtr = StablePtr (unsafeCoerce# 0#)
656 nullStablePtr = castPtrToStablePtr nullPtr
659 instance IArray UArray Int8 where
660 {-# INLINE unsafeArray #-}
661 unsafeArray lu ies = runST (unsafeArrayUArray lu ies 0)
662 #ifdef __GLASGOW_HASKELL__
663 {-# INLINE unsafeAt #-}
664 unsafeAt (UArray _ _ arr#) (I# i#) = I8# (indexInt8Array# arr# i#)
667 unsafeAt = unsafeAtBArray
669 {-# INLINE unsafeReplace #-}
670 unsafeReplace arr ies = runST (unsafeReplaceUArray arr ies)
671 {-# INLINE unsafeAccum #-}
672 unsafeAccum f arr ies = runST (unsafeAccumUArray f arr ies)
673 {-# INLINE unsafeAccumArray #-}
674 unsafeAccumArray f init lu ies = runST (unsafeAccumArrayUArray f init lu ies)
676 instance IArray UArray Int16 where
677 {-# INLINE unsafeArray #-}
678 unsafeArray lu ies = runST (unsafeArrayUArray lu ies 0)
679 #ifdef __GLASGOW_HASKELL__
680 {-# INLINE unsafeAt #-}
681 unsafeAt (UArray _ _ arr#) (I# i#) = I16# (indexInt16Array# arr# i#)
684 unsafeAt = unsafeAtBArray
686 {-# INLINE unsafeReplace #-}
687 unsafeReplace arr ies = runST (unsafeReplaceUArray arr ies)
688 {-# INLINE unsafeAccum #-}
689 unsafeAccum f arr ies = runST (unsafeAccumUArray f arr ies)
690 {-# INLINE unsafeAccumArray #-}
691 unsafeAccumArray f init lu ies = runST (unsafeAccumArrayUArray f init lu ies)
693 instance IArray UArray Int32 where
694 {-# INLINE unsafeArray #-}
695 unsafeArray lu ies = runST (unsafeArrayUArray lu ies 0)
696 #ifdef __GLASGOW_HASKELL__
697 {-# INLINE unsafeAt #-}
698 unsafeAt (UArray _ _ arr#) (I# i#) = I32# (indexInt32Array# arr# i#)
701 unsafeAt = unsafeAtBArray
703 {-# INLINE unsafeReplace #-}
704 unsafeReplace arr ies = runST (unsafeReplaceUArray arr ies)
705 {-# INLINE unsafeAccum #-}
706 unsafeAccum f arr ies = runST (unsafeAccumUArray f arr ies)
707 {-# INLINE unsafeAccumArray #-}
708 unsafeAccumArray f init lu ies = runST (unsafeAccumArrayUArray f init lu ies)
710 instance IArray UArray Int64 where
711 {-# INLINE unsafeArray #-}
712 unsafeArray lu ies = runST (unsafeArrayUArray lu ies 0)
713 #ifdef __GLASGOW_HASKELL__
714 {-# INLINE unsafeAt #-}
715 unsafeAt (UArray _ _ arr#) (I# i#) = I64# (indexInt64Array# arr# i#)
718 unsafeAt = unsafeAtBArray
720 {-# INLINE unsafeReplace #-}
721 unsafeReplace arr ies = runST (unsafeReplaceUArray arr ies)
722 {-# INLINE unsafeAccum #-}
723 unsafeAccum f arr ies = runST (unsafeAccumUArray f arr ies)
724 {-# INLINE unsafeAccumArray #-}
725 unsafeAccumArray f init lu ies = runST (unsafeAccumArrayUArray f init lu ies)
727 instance IArray UArray Word8 where
728 {-# INLINE unsafeArray #-}
729 unsafeArray lu ies = runST (unsafeArrayUArray lu ies 0)
730 #ifdef __GLASGOW_HASKELL__
731 {-# INLINE unsafeAt #-}
732 unsafeAt (UArray _ _ arr#) (I# i#) = W8# (indexWord8Array# arr# i#)
735 unsafeAt = unsafeAtBArray
737 {-# INLINE unsafeReplace #-}
738 unsafeReplace arr ies = runST (unsafeReplaceUArray arr ies)
739 {-# INLINE unsafeAccum #-}
740 unsafeAccum f arr ies = runST (unsafeAccumUArray f arr ies)
741 {-# INLINE unsafeAccumArray #-}
742 unsafeAccumArray f init lu ies = runST (unsafeAccumArrayUArray f init lu ies)
744 instance IArray UArray Word16 where
745 {-# INLINE unsafeArray #-}
746 unsafeArray lu ies = runST (unsafeArrayUArray lu ies 0)
747 #ifdef __GLASGOW_HASKELL__
748 {-# INLINE unsafeAt #-}
749 unsafeAt (UArray _ _ arr#) (I# i#) = W16# (indexWord16Array# arr# i#)
752 unsafeAt = unsafeAtBArray
754 {-# INLINE unsafeReplace #-}
755 unsafeReplace arr ies = runST (unsafeReplaceUArray arr ies)
756 {-# INLINE unsafeAccum #-}
757 unsafeAccum f arr ies = runST (unsafeAccumUArray f arr ies)
758 {-# INLINE unsafeAccumArray #-}
759 unsafeAccumArray f init lu ies = runST (unsafeAccumArrayUArray f init lu ies)
761 instance IArray UArray Word32 where
762 {-# INLINE unsafeArray #-}
763 unsafeArray lu ies = runST (unsafeArrayUArray lu ies 0)
764 #ifdef __GLASGOW_HASKELL__
765 {-# INLINE unsafeAt #-}
766 unsafeAt (UArray _ _ arr#) (I# i#) = W32# (indexWord32Array# arr# i#)
769 unsafeAt = unsafeAtBArray
771 {-# INLINE unsafeReplace #-}
772 unsafeReplace arr ies = runST (unsafeReplaceUArray arr ies)
773 {-# INLINE unsafeAccum #-}
774 unsafeAccum f arr ies = runST (unsafeAccumUArray f arr ies)
775 {-# INLINE unsafeAccumArray #-}
776 unsafeAccumArray f init lu ies = runST (unsafeAccumArrayUArray f init lu ies)
778 instance IArray UArray Word64 where
779 {-# INLINE unsafeArray #-}
780 unsafeArray lu ies = runST (unsafeArrayUArray lu ies 0)
781 #ifdef __GLASGOW_HASKELL__
782 {-# INLINE unsafeAt #-}
783 unsafeAt (UArray _ _ arr#) (I# i#) = W64# (indexWord64Array# arr# i#)
786 unsafeAt = unsafeAtBArray
788 {-# INLINE unsafeReplace #-}
789 unsafeReplace arr ies = runST (unsafeReplaceUArray arr ies)
790 {-# INLINE unsafeAccum #-}
791 unsafeAccum f arr ies = runST (unsafeAccumUArray f arr ies)
792 {-# INLINE unsafeAccumArray #-}
793 unsafeAccumArray f init lu ies = runST (unsafeAccumArrayUArray f init lu ies)
795 instance Ix ix => Eq (UArray ix Bool) where
798 instance Ix ix => Eq (UArray ix Char) where
801 instance Ix ix => Eq (UArray ix Int) where
804 instance Ix ix => Eq (UArray ix Word) where
807 instance Ix ix => Eq (UArray ix (Ptr a)) where
810 instance Ix ix => Eq (UArray ix (FunPtr a)) where
813 instance Ix ix => Eq (UArray ix Float) where
816 instance Ix ix => Eq (UArray ix Double) where
819 #ifdef __GLASGOW_HASKELL__
820 instance Ix ix => Eq (UArray ix (StablePtr a)) where
824 instance Ix ix => Eq (UArray ix Int8) where
827 instance Ix ix => Eq (UArray ix Int16) where
830 instance Ix ix => Eq (UArray ix Int32) where
833 instance Ix ix => Eq (UArray ix Int64) where
836 instance Ix ix => Eq (UArray ix Word8) where
839 instance Ix ix => Eq (UArray ix Word16) where
842 instance Ix ix => Eq (UArray ix Word32) where
845 instance Ix ix => Eq (UArray ix Word64) where
848 instance Ix ix => Ord (UArray ix Bool) where
851 instance Ix ix => Ord (UArray ix Char) where
854 instance Ix ix => Ord (UArray ix Int) where
857 instance Ix ix => Ord (UArray ix Word) where
860 instance Ix ix => Ord (UArray ix (Ptr a)) where
863 instance Ix ix => Ord (UArray ix (FunPtr a)) where
866 instance Ix ix => Ord (UArray ix Float) where
869 instance Ix ix => Ord (UArray ix Double) where
872 instance Ix ix => Ord (UArray ix Int8) where
875 instance Ix ix => Ord (UArray ix Int16) where
878 instance Ix ix => Ord (UArray ix Int32) where
881 instance Ix ix => Ord (UArray ix Int64) where
884 instance Ix ix => Ord (UArray ix Word8) where
887 instance Ix ix => Ord (UArray ix Word16) where
890 instance Ix ix => Ord (UArray ix Word32) where
893 instance Ix ix => Ord (UArray ix Word64) where
896 instance (Ix ix, Show ix) => Show (UArray ix Bool) where
897 showsPrec = showsIArray
899 instance (Ix ix, Show ix) => Show (UArray ix Char) where
900 showsPrec = showsIArray
902 instance (Ix ix, Show ix) => Show (UArray ix Int) where
903 showsPrec = showsIArray
905 instance (Ix ix, Show ix) => Show (UArray ix Word) where
906 showsPrec = showsIArray
908 instance (Ix ix, Show ix) => Show (UArray ix Float) where
909 showsPrec = showsIArray
911 instance (Ix ix, Show ix) => Show (UArray ix Double) where
912 showsPrec = showsIArray
914 instance (Ix ix, Show ix) => Show (UArray ix Int8) where
915 showsPrec = showsIArray
917 instance (Ix ix, Show ix) => Show (UArray ix Int16) where
918 showsPrec = showsIArray
920 instance (Ix ix, Show ix) => Show (UArray ix Int32) where
921 showsPrec = showsIArray
923 instance (Ix ix, Show ix) => Show (UArray ix Int64) where
924 showsPrec = showsIArray
926 instance (Ix ix, Show ix) => Show (UArray ix Word8) where
927 showsPrec = showsIArray
929 instance (Ix ix, Show ix) => Show (UArray ix Word16) where
930 showsPrec = showsIArray
932 instance (Ix ix, Show ix) => Show (UArray ix Word32) where
933 showsPrec = showsIArray
935 instance (Ix ix, Show ix) => Show (UArray ix Word64) where
936 showsPrec = showsIArray
938 -----------------------------------------------------------------------------
941 {-# NOINLINE arrEleBottom #-}
943 arrEleBottom = error "MArray: undefined array element"
945 {-| Class of mutable array types.
947 An array type has the form @(a i e)@ where @a@ is the array type
948 constructor (kind @* -> * -> *@), @i@ is the index type (a member of
949 the class 'Ix'), and @e@ is the element type.
951 The @MArray@ class is parameterised over both @a@ and @e@ (so that
952 instances specialised to certain element types can be defined, in the
953 same way as for 'IArray'), and also over the type of the monad, @m@,
954 in which the mutable array will be manipulated.
956 class (HasBounds a, Monad m) => MArray a e m where
958 -- | Builds a new array, with every element initialised to the supplied
960 newArray :: Ix i => (i,i) -> e -> m (a i e)
962 -- | Builds a new array, with every element initialised to undefined.
963 newArray_ :: Ix i => (i,i) -> m (a i e)
965 unsafeRead :: Ix i => a i e -> Int -> m e
966 unsafeWrite :: Ix i => a i e -> Int -> e -> m ()
968 {-# INLINE newArray #-}
969 -- The INLINE is crucial, because until we know at least which monad
970 -- we are in, the code below allocates like crazy. So inline it,
971 -- in the hope that the context will know the monad.
972 newArray (l,u) init = do
973 marr <- newArray_ (l,u)
974 sequence_ [unsafeWrite marr i init | i <- [0 .. rangeSize (l,u) - 1]]
977 newArray_ (l,u) = newArray (l,u) arrEleBottom
979 -- newArray takes an initialiser which all elements of
980 -- the newly created array are initialised to. newArray_ takes
981 -- no initialiser, it is assumed that the array is initialised with
982 -- "undefined" values.
984 -- why not omit newArray_? Because in the unboxed array case we would
985 -- like to omit the initialisation altogether if possible. We can't do
986 -- this for boxed arrays, because the elements must all have valid values
987 -- at all times in case of garbage collection.
989 -- why not omit newArray? Because in the boxed case, we can omit the
990 -- default initialisation with undefined values if we *do* know the
991 -- initial value and it is constant for all elements.
993 {-# INLINE newListArray #-}
994 -- | Constructs a mutable array from a list of initial elements.
995 -- The list gives the elements of the array in ascending order
996 -- beginning with the lowest index.
997 newListArray :: (MArray a e m, Ix i) => (i,i) -> [e] -> m (a i e)
998 newListArray (l,u) es = do
999 marr <- newArray_ (l,u)
1000 let n = rangeSize (l,u)
1001 let fillFromList i xs | i == n = return ()
1002 | otherwise = case xs of
1004 y:ys -> unsafeWrite marr i y >> fillFromList (i+1) ys
1008 {-# INLINE readArray #-}
1009 -- | Read an element from a mutable array
1010 readArray :: (MArray a e m, Ix i) => a i e -> i -> m e
1011 readArray marr i = case bounds marr of
1012 (l,u) -> unsafeRead marr (index (l,u) i)
1014 {-# INLINE writeArray #-}
1015 -- | Write an element in a mutable array
1016 writeArray :: (MArray a e m, Ix i) => a i e -> i -> e -> m ()
1017 writeArray marr i e = case bounds marr of
1018 (l,u) -> unsafeWrite marr (index (l,u) i) e
1020 {-# INLINE getElems #-}
1021 -- | Return a list of all the elements of a mutable array
1022 getElems :: (MArray a e m, Ix i) => a i e -> m [e]
1023 getElems marr = case bounds marr of
1024 (l,u) -> sequence [unsafeRead marr i | i <- [0 .. rangeSize (l,u) - 1]]
1026 {-# INLINE getAssocs #-}
1027 -- | Return a list of all the associations of a mutable array, in
1029 getAssocs :: (MArray a e m, Ix i) => a i e -> m [(i, e)]
1030 getAssocs marr = case bounds marr of
1031 (l,u) -> sequence [do e <- unsafeRead marr (index (l,u) i); return (i,e)
1034 {-# INLINE mapArray #-}
1035 -- | Constructs a new array derived from the original array by applying a
1036 -- function to each of the elements.
1037 mapArray :: (MArray a e' m, MArray a e m, Ix i) => (e' -> e) -> a i e' -> m (a i e)
1038 mapArray f marr = case bounds marr of
1040 marr' <- newArray_ (l,u)
1042 e <- unsafeRead marr i
1043 unsafeWrite marr' i (f e)
1044 | i <- [0 .. rangeSize (l,u) - 1]]
1047 {-# INLINE mapIndices #-}
1048 -- | Constructs a new array derived from the original array by applying a
1049 -- function to each of the indices.
1050 mapIndices :: (MArray a e m, Ix i, Ix j) => (i,i) -> (i -> j) -> a j e -> m (a i e)
1051 mapIndices (l,u) f marr = do
1052 marr' <- newArray_ (l,u)
1054 e <- readArray marr (f i)
1055 unsafeWrite marr' (unsafeIndex (l,u) i) e
1059 -----------------------------------------------------------------------------
1060 -- Polymorphic non-strict mutable arrays (ST monad)
1062 instance HasBounds (STArray s) where
1063 {-# INLINE bounds #-}
1064 bounds = ArrST.boundsSTArray
1066 instance MArray (STArray s) e (ST s) where
1067 {-# INLINE newArray #-}
1068 newArray = ArrST.newSTArray
1069 {-# INLINE unsafeRead #-}
1070 unsafeRead = ArrST.unsafeReadSTArray
1071 {-# INLINE unsafeWrite #-}
1072 unsafeWrite = ArrST.unsafeWriteSTArray
1074 -----------------------------------------------------------------------------
1075 -- Flat unboxed mutable arrays (ST monad)
1077 -- | A mutable array with unboxed elements, that can be manipulated in
1078 -- the 'ST' monad. The type arguments are as follows:
1080 -- * @s@: the state variable argument for the 'ST' type
1082 -- * @i@: the index type of the array (should be an instance of @Ix@)
1084 -- * @e@: the element type of the array. Only certain element types
1087 -- An 'STUArray' will generally be more efficient (in terms of both time
1088 -- and space) than the equivalent boxed version ('STArray') with the same
1089 -- element type. However, 'STUArray' is strict in its elements - so
1090 -- don\'t use 'STUArray' if you require the non-strictness that
1091 -- 'STArray' provides.
1092 #ifdef __GLASGOW_HASKELL__
1093 data STUArray s i a = STUArray !i !i (MutableByteArray# s)
1096 data STUArray s i a = STUArray !i !i !(MutableByteArray s)
1099 INSTANCE_TYPEABLE3(STUArray,stUArrayTc,"STUArray")
1101 instance HasBounds (STUArray s) where
1102 {-# INLINE bounds #-}
1103 bounds (STUArray l u _) = (l,u)
1105 #ifdef __GLASGOW_HASKELL__
1106 instance MArray (STUArray s) Bool (ST s) where
1107 {-# INLINE newArray #-}
1108 newArray (l,u) init = ST $ \s1# ->
1109 case rangeSize (l,u) of { I# n# ->
1110 case newByteArray# (bOOL_SCALE n#) s1# of { (# s2#, marr# #) ->
1111 case bOOL_WORD_SCALE n# of { n'# ->
1112 let loop i# s3# | i# ==# n'# = s3#
1114 case writeWordArray# marr# i# e# s3# of { s4# ->
1115 loop (i# +# 1#) s4# } in
1116 case loop 0# s2# of { s3# ->
1117 (# s3#, STUArray l u marr# #) }}}}
1119 W# e# = if init then maxBound else 0
1120 {-# INLINE newArray_ #-}
1121 newArray_ (l,u) = ST $ \s1# ->
1122 case rangeSize (l,u) of { I# n# ->
1123 case newByteArray# (bOOL_SCALE n#) s1# of { (# s2#, marr# #) ->
1124 (# s2#, STUArray l u marr# #) }}
1125 {-# INLINE unsafeRead #-}
1126 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1127 case readWordArray# marr# (bOOL_INDEX i#) s1# of { (# s2#, e# #) ->
1128 (# s2#, (e# `and#` bOOL_BIT i#) `neWord#` int2Word# 0# #) }
1129 {-# INLINE unsafeWrite #-}
1130 unsafeWrite (STUArray _ _ marr#) (I# i#) e = ST $ \s1# ->
1131 case bOOL_INDEX i# of { j# ->
1132 case readWordArray# marr# j# s1# of { (# s2#, old# #) ->
1133 case if e then old# `or#` bOOL_BIT i#
1134 else old# `and#` bOOL_NOT_BIT i# of { e# ->
1135 case writeWordArray# marr# j# e# s2# of { s3# ->
1138 instance MArray (STUArray s) Char (ST s) where
1139 {-# INLINE newArray_ #-}
1140 newArray_ (l,u) = ST $ \s1# ->
1141 case rangeSize (l,u) of { I# n# ->
1142 case newByteArray# (n# *# 4#) s1# of { (# s2#, marr# #) ->
1143 (# s2#, STUArray l u marr# #) }}
1144 {-# INLINE unsafeRead #-}
1145 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1146 case readWideCharArray# marr# i# s1# of { (# s2#, e# #) ->
1148 {-# INLINE unsafeWrite #-}
1149 unsafeWrite (STUArray _ _ marr#) (I# i#) (C# e#) = ST $ \s1# ->
1150 case writeWideCharArray# marr# i# e# s1# of { s2# ->
1153 instance MArray (STUArray s) Int (ST s) where
1154 {-# INLINE newArray_ #-}
1155 newArray_ (l,u) = ST $ \s1# ->
1156 case rangeSize (l,u) of { I# n# ->
1157 case newByteArray# (wORD_SCALE n#) s1# of { (# s2#, marr# #) ->
1158 (# s2#, STUArray l u marr# #) }}
1159 {-# INLINE unsafeRead #-}
1160 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1161 case readIntArray# marr# i# s1# of { (# s2#, e# #) ->
1163 {-# INLINE unsafeWrite #-}
1164 unsafeWrite (STUArray _ _ marr#) (I# i#) (I# e#) = ST $ \s1# ->
1165 case writeIntArray# marr# i# e# s1# of { s2# ->
1168 instance MArray (STUArray s) Word (ST s) where
1169 {-# INLINE newArray_ #-}
1170 newArray_ (l,u) = ST $ \s1# ->
1171 case rangeSize (l,u) of { I# n# ->
1172 case newByteArray# (wORD_SCALE n#) s1# of { (# s2#, marr# #) ->
1173 (# s2#, STUArray l u marr# #) }}
1174 {-# INLINE unsafeRead #-}
1175 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1176 case readWordArray# marr# i# s1# of { (# s2#, e# #) ->
1178 {-# INLINE unsafeWrite #-}
1179 unsafeWrite (STUArray _ _ marr#) (I# i#) (W# e#) = ST $ \s1# ->
1180 case writeWordArray# marr# i# e# s1# of { s2# ->
1183 instance MArray (STUArray s) (Ptr a) (ST s) where
1184 {-# INLINE newArray_ #-}
1185 newArray_ (l,u) = ST $ \s1# ->
1186 case rangeSize (l,u) of { I# n# ->
1187 case newByteArray# (wORD_SCALE n#) s1# of { (# s2#, marr# #) ->
1188 (# s2#, STUArray l u marr# #) }}
1189 {-# INLINE unsafeRead #-}
1190 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1191 case readAddrArray# marr# i# s1# of { (# s2#, e# #) ->
1193 {-# INLINE unsafeWrite #-}
1194 unsafeWrite (STUArray _ _ marr#) (I# i#) (Ptr e#) = ST $ \s1# ->
1195 case writeAddrArray# marr# i# e# s1# of { s2# ->
1198 instance MArray (STUArray s) (FunPtr a) (ST s) where
1199 {-# INLINE newArray_ #-}
1200 newArray_ (l,u) = ST $ \s1# ->
1201 case rangeSize (l,u) of { I# n# ->
1202 case newByteArray# (wORD_SCALE n#) s1# of { (# s2#, marr# #) ->
1203 (# s2#, STUArray l u marr# #) }}
1204 {-# INLINE unsafeRead #-}
1205 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1206 case readAddrArray# marr# i# s1# of { (# s2#, e# #) ->
1207 (# s2#, FunPtr e# #) }
1208 {-# INLINE unsafeWrite #-}
1209 unsafeWrite (STUArray _ _ marr#) (I# i#) (FunPtr e#) = ST $ \s1# ->
1210 case writeAddrArray# marr# i# e# s1# of { s2# ->
1213 instance MArray (STUArray s) Float (ST s) where
1214 {-# INLINE newArray_ #-}
1215 newArray_ (l,u) = ST $ \s1# ->
1216 case rangeSize (l,u) of { I# n# ->
1217 case newByteArray# (fLOAT_SCALE n#) s1# of { (# s2#, marr# #) ->
1218 (# s2#, STUArray l u marr# #) }}
1219 {-# INLINE unsafeRead #-}
1220 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1221 case readFloatArray# marr# i# s1# of { (# s2#, e# #) ->
1223 {-# INLINE unsafeWrite #-}
1224 unsafeWrite (STUArray _ _ marr#) (I# i#) (F# e#) = ST $ \s1# ->
1225 case writeFloatArray# marr# i# e# s1# of { s2# ->
1228 instance MArray (STUArray s) Double (ST s) where
1229 {-# INLINE newArray_ #-}
1230 newArray_ (l,u) = ST $ \s1# ->
1231 case rangeSize (l,u) of { I# n# ->
1232 case newByteArray# (dOUBLE_SCALE n#) s1# of { (# s2#, marr# #) ->
1233 (# s2#, STUArray l u marr# #) }}
1234 {-# INLINE unsafeRead #-}
1235 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1236 case readDoubleArray# marr# i# s1# of { (# s2#, e# #) ->
1238 {-# INLINE unsafeWrite #-}
1239 unsafeWrite (STUArray _ _ marr#) (I# i#) (D# e#) = ST $ \s1# ->
1240 case writeDoubleArray# marr# i# e# s1# of { s2# ->
1243 instance MArray (STUArray s) (StablePtr a) (ST s) where
1244 {-# INLINE newArray_ #-}
1245 newArray_ (l,u) = ST $ \s1# ->
1246 case rangeSize (l,u) of { I# n# ->
1247 case newByteArray# (wORD_SCALE n#) s1# of { (# s2#, marr# #) ->
1248 (# s2#, STUArray l u marr# #) }}
1249 {-# INLINE unsafeRead #-}
1250 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1251 case readStablePtrArray# marr# i# s1# of { (# s2#, e# #) ->
1252 (# s2# , StablePtr e# #) }
1253 {-# INLINE unsafeWrite #-}
1254 unsafeWrite (STUArray _ _ marr#) (I# i#) (StablePtr e#) = ST $ \s1# ->
1255 case writeStablePtrArray# marr# i# e# s1# of { s2# ->
1258 instance MArray (STUArray s) Int8 (ST s) where
1259 {-# INLINE newArray_ #-}
1260 newArray_ (l,u) = ST $ \s1# ->
1261 case rangeSize (l,u) of { I# n# ->
1262 case newByteArray# n# s1# of { (# s2#, marr# #) ->
1263 (# s2#, STUArray l u marr# #) }}
1264 {-# INLINE unsafeRead #-}
1265 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1266 case readInt8Array# marr# i# s1# of { (# s2#, e# #) ->
1268 {-# INLINE unsafeWrite #-}
1269 unsafeWrite (STUArray _ _ marr#) (I# i#) (I8# e#) = ST $ \s1# ->
1270 case writeInt8Array# marr# i# e# s1# of { s2# ->
1273 instance MArray (STUArray s) Int16 (ST s) where
1274 {-# INLINE newArray_ #-}
1275 newArray_ (l,u) = ST $ \s1# ->
1276 case rangeSize (l,u) of { I# n# ->
1277 case newByteArray# (n# *# 2#) s1# of { (# s2#, marr# #) ->
1278 (# s2#, STUArray l u marr# #) }}
1279 {-# INLINE unsafeRead #-}
1280 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1281 case readInt16Array# marr# i# s1# of { (# s2#, e# #) ->
1282 (# s2#, I16# e# #) }
1283 {-# INLINE unsafeWrite #-}
1284 unsafeWrite (STUArray _ _ marr#) (I# i#) (I16# e#) = ST $ \s1# ->
1285 case writeInt16Array# marr# i# e# s1# of { s2# ->
1288 instance MArray (STUArray s) Int32 (ST s) where
1289 {-# INLINE newArray_ #-}
1290 newArray_ (l,u) = ST $ \s1# ->
1291 case rangeSize (l,u) of { I# n# ->
1292 case newByteArray# (n# *# 4#) s1# of { (# s2#, marr# #) ->
1293 (# s2#, STUArray l u marr# #) }}
1294 {-# INLINE unsafeRead #-}
1295 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1296 case readInt32Array# marr# i# s1# of { (# s2#, e# #) ->
1297 (# s2#, I32# e# #) }
1298 {-# INLINE unsafeWrite #-}
1299 unsafeWrite (STUArray _ _ marr#) (I# i#) (I32# e#) = ST $ \s1# ->
1300 case writeInt32Array# marr# i# e# s1# of { s2# ->
1303 instance MArray (STUArray s) Int64 (ST s) where
1304 {-# INLINE newArray_ #-}
1305 newArray_ (l,u) = ST $ \s1# ->
1306 case rangeSize (l,u) of { I# n# ->
1307 case newByteArray# (n# *# 8#) s1# of { (# s2#, marr# #) ->
1308 (# s2#, STUArray l u marr# #) }}
1309 {-# INLINE unsafeRead #-}
1310 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1311 case readInt64Array# marr# i# s1# of { (# s2#, e# #) ->
1312 (# s2#, I64# e# #) }
1313 {-# INLINE unsafeWrite #-}
1314 unsafeWrite (STUArray _ _ marr#) (I# i#) (I64# e#) = ST $ \s1# ->
1315 case writeInt64Array# marr# i# e# s1# of { s2# ->
1318 instance MArray (STUArray s) Word8 (ST s) where
1319 {-# INLINE newArray_ #-}
1320 newArray_ (l,u) = ST $ \s1# ->
1321 case rangeSize (l,u) of { I# n# ->
1322 case newByteArray# n# s1# of { (# s2#, marr# #) ->
1323 (# s2#, STUArray l u marr# #) }}
1324 {-# INLINE unsafeRead #-}
1325 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1326 case readWord8Array# marr# i# s1# of { (# s2#, e# #) ->
1328 {-# INLINE unsafeWrite #-}
1329 unsafeWrite (STUArray _ _ marr#) (I# i#) (W8# e#) = ST $ \s1# ->
1330 case writeWord8Array# marr# i# e# s1# of { s2# ->
1333 instance MArray (STUArray s) Word16 (ST s) where
1334 {-# INLINE newArray_ #-}
1335 newArray_ (l,u) = ST $ \s1# ->
1336 case rangeSize (l,u) of { I# n# ->
1337 case newByteArray# (n# *# 2#) s1# of { (# s2#, marr# #) ->
1338 (# s2#, STUArray l u marr# #) }}
1339 {-# INLINE unsafeRead #-}
1340 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1341 case readWord16Array# marr# i# s1# of { (# s2#, e# #) ->
1342 (# s2#, W16# e# #) }
1343 {-# INLINE unsafeWrite #-}
1344 unsafeWrite (STUArray _ _ marr#) (I# i#) (W16# e#) = ST $ \s1# ->
1345 case writeWord16Array# marr# i# e# s1# of { s2# ->
1348 instance MArray (STUArray s) Word32 (ST s) where
1349 {-# INLINE newArray_ #-}
1350 newArray_ (l,u) = ST $ \s1# ->
1351 case rangeSize (l,u) of { I# n# ->
1352 case newByteArray# (n# *# 4#) s1# of { (# s2#, marr# #) ->
1353 (# s2#, STUArray l u marr# #) }}
1354 {-# INLINE unsafeRead #-}
1355 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1356 case readWord32Array# marr# i# s1# of { (# s2#, e# #) ->
1357 (# s2#, W32# e# #) }
1358 {-# INLINE unsafeWrite #-}
1359 unsafeWrite (STUArray _ _ marr#) (I# i#) (W32# e#) = ST $ \s1# ->
1360 case writeWord32Array# marr# i# e# s1# of { s2# ->
1363 instance MArray (STUArray s) Word64 (ST s) where
1364 {-# INLINE newArray_ #-}
1365 newArray_ (l,u) = ST $ \s1# ->
1366 case rangeSize (l,u) of { I# n# ->
1367 case newByteArray# (n# *# 8#) s1# of { (# s2#, marr# #) ->
1368 (# s2#, STUArray l u marr# #) }}
1369 {-# INLINE unsafeRead #-}
1370 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1371 case readWord64Array# marr# i# s1# of { (# s2#, e# #) ->
1372 (# s2#, W64# e# #) }
1373 {-# INLINE unsafeWrite #-}
1374 unsafeWrite (STUArray _ _ marr#) (I# i#) (W64# e#) = ST $ \s1# ->
1375 case writeWord64Array# marr# i# e# s1# of { s2# ->
1378 -----------------------------------------------------------------------------
1379 -- Translation between elements and bytes
1381 bOOL_SCALE, bOOL_WORD_SCALE,
1382 wORD_SCALE, dOUBLE_SCALE, fLOAT_SCALE :: Int# -> Int#
1383 bOOL_SCALE n# = (n# +# last#) `uncheckedIShiftRA#` 3#
1384 where I# last# = SIZEOF_HSWORD * 8 - 1
1385 bOOL_WORD_SCALE n# = bOOL_INDEX (n# +# last#)
1386 where I# last# = SIZEOF_HSWORD * 8 - 1
1387 wORD_SCALE n# = scale# *# n# where I# scale# = SIZEOF_HSWORD
1388 dOUBLE_SCALE n# = scale# *# n# where I# scale# = SIZEOF_HSDOUBLE
1389 fLOAT_SCALE n# = scale# *# n# where I# scale# = SIZEOF_HSFLOAT
1391 bOOL_INDEX :: Int# -> Int#
1392 #if SIZEOF_HSWORD == 4
1393 bOOL_INDEX i# = i# `uncheckedIShiftRA#` 5#
1394 #elif SIZEOF_HSWORD == 8
1395 bOOL_INDEX i# = i# `uncheckedIShiftRA#` 6#
1398 bOOL_BIT, bOOL_NOT_BIT :: Int# -> Word#
1399 bOOL_BIT n# = int2Word# 1# `uncheckedShiftL#` (word2Int# (int2Word# n# `and#` mask#))
1400 where W# mask# = SIZEOF_HSWORD * 8 - 1
1401 bOOL_NOT_BIT n# = bOOL_BIT n# `xor#` mb# where W# mb# = maxBound
1402 #endif /* __GLASGOW_HASKELL__ */
1405 newMBArray_ :: (Ix i, Storable e) => (i,i) -> ST s (STUArray s i e)
1406 newMBArray_ = makeArray undefined
1408 makeArray :: (Ix i, Storable e) => e -> (i,i) -> ST s (STUArray s i e)
1409 makeArray dummy (l,u) = do
1410 marr <- newMutableByteArray (rangeSize (l,u) * sizeOf dummy)
1411 return (STUArray l u marr)
1413 unsafeReadMBArray :: Storable e => STUArray s i e -> Int -> ST s e
1414 unsafeReadMBArray (STUArray _ _ marr) = readMutableByteArray marr
1416 unsafeWriteMBArray :: Storable e => STUArray s i e -> Int -> e -> ST s ()
1417 unsafeWriteMBArray (STUArray _ _ marr) = writeMutableByteArray marr
1419 instance MArray (STUArray s) Bool (ST s) where
1420 newArray_ (l,u) = do
1421 marr <- newMutableByteArray (bOOL_SCALE (rangeSize (l,u)))
1422 return (STUArray l u marr)
1423 unsafeRead (STUArray _ _ marr) i = do
1424 let ix = bOOL_INDEX i
1425 bit = bOOL_SUBINDEX i
1426 w <- readMutableByteArray marr ix
1427 return (testBit (w::BitSet) bit)
1428 unsafeWrite (STUArray _ _ marr) i e = do
1429 let ix = bOOL_INDEX i
1430 bit = bOOL_SUBINDEX i
1431 w <- readMutableByteArray marr ix
1432 writeMutableByteArray marr ix
1433 (if e then setBit (w::BitSet) bit else clearBit w bit)
1435 instance MArray (STUArray s) Char (ST s) where
1436 newArray_ = newMBArray_
1437 unsafeRead = unsafeReadMBArray
1438 unsafeWrite = unsafeWriteMBArray
1440 instance MArray (STUArray s) Int (ST s) where
1441 newArray_ = newMBArray_
1442 unsafeRead = unsafeReadMBArray
1443 unsafeWrite = unsafeWriteMBArray
1445 instance MArray (STUArray s) Word (ST s) where
1446 newArray_ = newMBArray_
1447 unsafeRead = unsafeReadMBArray
1448 unsafeWrite = unsafeWriteMBArray
1450 instance MArray (STUArray s) (Ptr a) (ST s) where
1451 newArray_ = newMBArray_
1452 unsafeRead = unsafeReadMBArray
1453 unsafeWrite = unsafeWriteMBArray
1455 instance MArray (STUArray s) (FunPtr a) (ST s) where
1456 newArray_ = newMBArray_
1457 unsafeRead = unsafeReadMBArray
1458 unsafeWrite = unsafeWriteMBArray
1460 instance MArray (STUArray s) Float (ST s) where
1461 newArray_ = newMBArray_
1462 unsafeRead = unsafeReadMBArray
1463 unsafeWrite = unsafeWriteMBArray
1465 instance MArray (STUArray s) Double (ST s) where
1466 newArray_ = newMBArray_
1467 unsafeRead = unsafeReadMBArray
1468 unsafeWrite = unsafeWriteMBArray
1470 instance MArray (STUArray s) (StablePtr a) (ST s) where
1471 newArray_ = newMBArray_
1472 unsafeRead = unsafeReadMBArray
1473 unsafeWrite = unsafeWriteMBArray
1475 instance MArray (STUArray s) Int8 (ST s) where
1476 newArray_ = newMBArray_
1477 unsafeRead = unsafeReadMBArray
1478 unsafeWrite = unsafeWriteMBArray
1480 instance MArray (STUArray s) Int16 (ST s) where
1481 newArray_ = newMBArray_
1482 unsafeRead = unsafeReadMBArray
1483 unsafeWrite = unsafeWriteMBArray
1485 instance MArray (STUArray s) Int32 (ST s) where
1486 newArray_ = newMBArray_
1487 unsafeRead = unsafeReadMBArray
1488 unsafeWrite = unsafeWriteMBArray
1490 instance MArray (STUArray s) Int64 (ST s) where
1491 newArray_ = newMBArray_
1492 unsafeRead = unsafeReadMBArray
1493 unsafeWrite = unsafeWriteMBArray
1495 instance MArray (STUArray s) Word8 (ST s) where
1496 newArray_ = newMBArray_
1497 unsafeRead = unsafeReadMBArray
1498 unsafeWrite = unsafeWriteMBArray
1500 instance MArray (STUArray s) Word16 (ST s) where
1501 newArray_ = newMBArray_
1502 unsafeRead = unsafeReadMBArray
1503 unsafeWrite = unsafeWriteMBArray
1505 instance MArray (STUArray s) Word32 (ST s) where
1506 newArray_ = newMBArray_
1507 unsafeRead = unsafeReadMBArray
1508 unsafeWrite = unsafeWriteMBArray
1510 instance MArray (STUArray s) Word64 (ST s) where
1511 newArray_ = newMBArray_
1512 unsafeRead = unsafeReadMBArray
1513 unsafeWrite = unsafeWriteMBArray
1517 bitSetSize = bitSize (0::BitSet)
1519 bOOL_SCALE :: Int -> Int
1520 bOOL_SCALE n = (n + bitSetSize - 1) `div` bitSetSize
1522 bOOL_INDEX :: Int -> Int
1523 bOOL_INDEX i = i `div` bitSetSize
1525 bOOL_SUBINDEX :: Int -> Int
1526 bOOL_SUBINDEX i = i `mod` bitSetSize
1527 #endif /* __HUGS__ */
1529 -----------------------------------------------------------------------------
1532 -- | Converts a mutable array (any instance of 'MArray') to an
1533 -- immutable array (any instance of 'IArray') by taking a complete
1535 freeze :: (Ix i, MArray a e m, IArray b e) => a i e -> m (b i e)
1536 freeze marr = case bounds marr of
1538 ies <- sequence [do e <- unsafeRead marr i; return (i,e)
1539 | i <- [0 .. rangeSize (l,u) - 1]]
1540 return (unsafeArray (l,u) ies)
1542 #ifdef __GLASGOW_HASKELL__
1543 freezeSTUArray :: Ix i => STUArray s i e -> ST s (UArray i e)
1544 freezeSTUArray (STUArray l u marr#) = ST $ \s1# ->
1545 case sizeofMutableByteArray# marr# of { n# ->
1546 case newByteArray# n# s1# of { (# s2#, marr'# #) ->
1547 case unsafeCoerce# memcpy marr'# marr# n# s2# of { (# s3#, () #) ->
1548 case unsafeFreezeByteArray# marr'# s3# of { (# s4#, arr# #) ->
1549 (# s4#, UArray l u arr# #) }}}}
1552 "freeze/STArray" freeze = ArrST.freezeSTArray
1553 "freeze/STUArray" freeze = freezeSTUArray
1555 #endif /* __GLASGOW_HASKELL__ */
1557 -- In-place conversion of mutable arrays to immutable ones places
1558 -- a proof obligation on the user: no other parts of your code can
1559 -- have a reference to the array at the point where you unsafely
1560 -- freeze it (and, subsequently mutate it, I suspect).
1563 Converts an mutable array into an immutable array. The
1564 implementation may either simply cast the array from
1565 one type to the other without copying the array, or it
1566 may take a full copy of the array.
1568 Note that because the array is possibly not copied, any subsequent
1569 modifications made to the mutable version of the array may be
1570 shared with the immutable version. It is safe to use, therefore, if
1571 the mutable version is never modified after the freeze operation.
1573 The non-copying implementation is supported between certain pairs
1574 of array types only; one constraint is that the array types must
1575 have identical representations. In GHC, The following pairs of
1576 array types have a non-copying O(1) implementation of
1577 'unsafeFreeze'. Because the optimised versions are enabled by
1578 specialisations, you will need to compile with optimisation (-O) to
1581 * 'Data.Array.IO.IOUArray' -> 'Data.Array.Unboxed.UArray'
1583 * 'Data.Array.ST.STUArray' -> 'Data.Array.Unboxed.UArray'
1585 * 'Data.Array.IO.IOArray' -> 'Data.Array.Array'
1587 * 'Data.Array.ST.STArray' -> 'Data.Array.Array'
1589 {-# INLINE unsafeFreeze #-}
1590 unsafeFreeze :: (Ix i, MArray a e m, IArray b e) => a i e -> m (b i e)
1591 unsafeFreeze = freeze
1594 "unsafeFreeze/STArray" unsafeFreeze = ArrST.unsafeFreezeSTArray
1595 "unsafeFreeze/STUArray" unsafeFreeze = unsafeFreezeSTUArray
1598 -----------------------------------------------------------------------------
1601 -- | Converts an immutable array (any instance of 'IArray') into a
1602 -- mutable array (any instance of 'MArray') by taking a complete copy
1604 thaw :: (Ix i, IArray a e, MArray b e m) => a i e -> m (b i e)
1605 thaw arr = case bounds arr of
1607 marr <- newArray_ (l,u)
1608 sequence_ [unsafeWrite marr i (unsafeAt arr i)
1609 | i <- [0 .. rangeSize (l,u) - 1]]
1612 #ifdef __GLASGOW_HASKELL__
1613 thawSTUArray :: Ix i => UArray i e -> ST s (STUArray s i e)
1614 thawSTUArray (UArray l u arr#) = ST $ \s1# ->
1615 case sizeofByteArray# arr# of { n# ->
1616 case newByteArray# n# s1# of { (# s2#, marr# #) ->
1617 case unsafeCoerce# memcpy marr# arr# n# s2# of { (# s3#, () #) ->
1618 (# s3#, STUArray l u marr# #) }}}
1620 foreign import ccall unsafe "memcpy"
1621 memcpy :: MutableByteArray# RealWorld -> ByteArray# -> Int# -> IO ()
1624 "thaw/STArray" thaw = ArrST.thawSTArray
1625 "thaw/STUArray" thaw = thawSTUArray
1627 #endif /* __GLASGOW_HASKELL__ */
1630 thawSTUArray :: Ix i => UArray i e -> ST s (STUArray s i e)
1631 thawSTUArray (UArray l u arr) = do
1632 marr <- thawByteArray arr
1633 return (STUArray l u marr)
1636 -- In-place conversion of immutable arrays to mutable ones places
1637 -- a proof obligation on the user: no other parts of your code can
1638 -- have a reference to the array at the point where you unsafely
1639 -- thaw it (and, subsequently mutate it, I suspect).
1642 Converts an immutable array into a mutable array. The
1643 implementation may either simply cast the array from
1644 one type to the other without copying the array, or it
1645 may take a full copy of the array.
1647 Note that because the array is possibly not copied, any subsequent
1648 modifications made to the mutable version of the array may be
1649 shared with the immutable version. It is safe to use, therefore, if
1650 the immutable version is never referenced again.
1652 The non-copying implementation is supported between certain pairs
1653 of array types only; one constraint is that the array types must
1654 have identical representations. In GHC, The following pairs of
1655 array types have a non-copying O(1) implementation of
1656 'unsafeFreeze'. Because the optimised versions are enabled by
1657 specialisations, you will need to compile with optimisation (-O) to
1660 * 'Data.Array.Unboxed.UArray' -> 'Data.Array.IO.IOUArray'
1662 * 'Data.Array.Unboxed.UArray' -> 'Data.Array.ST.STUArray'
1664 * 'Data.Array.Array' -> 'Data.Array.IO.IOArray'
1666 * 'Data.Array.Array' -> 'Data.Array.ST.STArray'
1668 {-# INLINE unsafeThaw #-}
1669 unsafeThaw :: (Ix i, IArray a e, MArray b e m) => a i e -> m (b i e)
1672 #ifdef __GLASGOW_HASKELL__
1673 {-# INLINE unsafeThawSTUArray #-}
1674 unsafeThawSTUArray :: Ix i => UArray i e -> ST s (STUArray s i e)
1675 unsafeThawSTUArray (UArray l u marr#) =
1676 return (STUArray l u (unsafeCoerce# marr#))
1679 "unsafeThaw/STArray" unsafeThaw = ArrST.unsafeThawSTArray
1680 "unsafeThaw/STUArray" unsafeThaw = unsafeThawSTUArray
1682 #endif /* __GLASGOW_HASKELL__ */
1684 -- | Casts an 'STUArray' with one element type into one with a
1685 -- different element type. All the elements of the resulting array
1686 -- are undefined (unless you know what you\'re doing...).
1688 #ifdef __GLASGOW_HASKELL__
1689 castSTUArray :: STUArray s ix a -> ST s (STUArray s ix b)
1690 castSTUArray (STUArray l u marr#) = return (STUArray l u marr#)
1694 castSTUArray :: STUArray s ix a -> ST s (STUArray s ix b)
1695 castSTUArray (STUArray l u marr) = return (STUArray l u marr)