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
1075 INSTANCE_TYPEABLE3(STArray,sTArrayTc,"STArray")
1078 -----------------------------------------------------------------------------
1079 -- Flat unboxed mutable arrays (ST monad)
1081 -- | A mutable array with unboxed elements, that can be manipulated in
1082 -- the 'ST' monad. The type arguments are as follows:
1084 -- * @s@: the state variable argument for the 'ST' type
1086 -- * @i@: the index type of the array (should be an instance of @Ix@)
1088 -- * @e@: the element type of the array. Only certain element types
1091 -- An 'STUArray' will generally be more efficient (in terms of both time
1092 -- and space) than the equivalent boxed version ('STArray') with the same
1093 -- element type. However, 'STUArray' is strict in its elements - so
1094 -- don\'t use 'STUArray' if you require the non-strictness that
1095 -- 'STArray' provides.
1096 #ifdef __GLASGOW_HASKELL__
1097 data STUArray s i a = STUArray !i !i (MutableByteArray# s)
1100 data STUArray s i a = STUArray !i !i !(MutableByteArray s)
1103 INSTANCE_TYPEABLE3(STUArray,stUArrayTc,"STUArray")
1105 instance HasBounds (STUArray s) where
1106 {-# INLINE bounds #-}
1107 bounds (STUArray l u _) = (l,u)
1109 #ifdef __GLASGOW_HASKELL__
1110 instance MArray (STUArray s) Bool (ST s) where
1111 {-# INLINE newArray #-}
1112 newArray (l,u) init = ST $ \s1# ->
1113 case rangeSize (l,u) of { I# n# ->
1114 case newByteArray# (bOOL_SCALE n#) s1# of { (# s2#, marr# #) ->
1115 case bOOL_WORD_SCALE n# of { n'# ->
1116 let loop i# s3# | i# ==# n'# = s3#
1118 case writeWordArray# marr# i# e# s3# of { s4# ->
1119 loop (i# +# 1#) s4# } in
1120 case loop 0# s2# of { s3# ->
1121 (# s3#, STUArray l u marr# #) }}}}
1123 W# e# = if init then maxBound else 0
1124 {-# INLINE newArray_ #-}
1125 newArray_ (l,u) = ST $ \s1# ->
1126 case rangeSize (l,u) of { I# n# ->
1127 case newByteArray# (bOOL_SCALE n#) s1# of { (# s2#, marr# #) ->
1128 (# s2#, STUArray l u marr# #) }}
1129 {-# INLINE unsafeRead #-}
1130 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1131 case readWordArray# marr# (bOOL_INDEX i#) s1# of { (# s2#, e# #) ->
1132 (# s2#, (e# `and#` bOOL_BIT i#) `neWord#` int2Word# 0# #) }
1133 {-# INLINE unsafeWrite #-}
1134 unsafeWrite (STUArray _ _ marr#) (I# i#) e = ST $ \s1# ->
1135 case bOOL_INDEX i# of { j# ->
1136 case readWordArray# marr# j# s1# of { (# s2#, old# #) ->
1137 case if e then old# `or#` bOOL_BIT i#
1138 else old# `and#` bOOL_NOT_BIT i# of { e# ->
1139 case writeWordArray# marr# j# e# s2# of { s3# ->
1142 instance MArray (STUArray s) Char (ST s) where
1143 {-# INLINE newArray_ #-}
1144 newArray_ (l,u) = ST $ \s1# ->
1145 case rangeSize (l,u) of { I# n# ->
1146 case newByteArray# (n# *# 4#) s1# of { (# s2#, marr# #) ->
1147 (# s2#, STUArray l u marr# #) }}
1148 {-# INLINE unsafeRead #-}
1149 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1150 case readWideCharArray# marr# i# s1# of { (# s2#, e# #) ->
1152 {-# INLINE unsafeWrite #-}
1153 unsafeWrite (STUArray _ _ marr#) (I# i#) (C# e#) = ST $ \s1# ->
1154 case writeWideCharArray# marr# i# e# s1# of { s2# ->
1157 instance MArray (STUArray s) Int (ST s) where
1158 {-# INLINE newArray_ #-}
1159 newArray_ (l,u) = ST $ \s1# ->
1160 case rangeSize (l,u) of { I# n# ->
1161 case newByteArray# (wORD_SCALE n#) s1# of { (# s2#, marr# #) ->
1162 (# s2#, STUArray l u marr# #) }}
1163 {-# INLINE unsafeRead #-}
1164 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1165 case readIntArray# marr# i# s1# of { (# s2#, e# #) ->
1167 {-# INLINE unsafeWrite #-}
1168 unsafeWrite (STUArray _ _ marr#) (I# i#) (I# e#) = ST $ \s1# ->
1169 case writeIntArray# marr# i# e# s1# of { s2# ->
1172 instance MArray (STUArray s) Word (ST s) where
1173 {-# INLINE newArray_ #-}
1174 newArray_ (l,u) = ST $ \s1# ->
1175 case rangeSize (l,u) of { I# n# ->
1176 case newByteArray# (wORD_SCALE n#) s1# of { (# s2#, marr# #) ->
1177 (# s2#, STUArray l u marr# #) }}
1178 {-# INLINE unsafeRead #-}
1179 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1180 case readWordArray# marr# i# s1# of { (# s2#, e# #) ->
1182 {-# INLINE unsafeWrite #-}
1183 unsafeWrite (STUArray _ _ marr#) (I# i#) (W# e#) = ST $ \s1# ->
1184 case writeWordArray# marr# i# e# s1# of { s2# ->
1187 instance MArray (STUArray s) (Ptr a) (ST s) where
1188 {-# INLINE newArray_ #-}
1189 newArray_ (l,u) = ST $ \s1# ->
1190 case rangeSize (l,u) of { I# n# ->
1191 case newByteArray# (wORD_SCALE n#) s1# of { (# s2#, marr# #) ->
1192 (# s2#, STUArray l u marr# #) }}
1193 {-# INLINE unsafeRead #-}
1194 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1195 case readAddrArray# marr# i# s1# of { (# s2#, e# #) ->
1197 {-# INLINE unsafeWrite #-}
1198 unsafeWrite (STUArray _ _ marr#) (I# i#) (Ptr e#) = ST $ \s1# ->
1199 case writeAddrArray# marr# i# e# s1# of { s2# ->
1202 instance MArray (STUArray s) (FunPtr a) (ST s) where
1203 {-# INLINE newArray_ #-}
1204 newArray_ (l,u) = ST $ \s1# ->
1205 case rangeSize (l,u) of { I# n# ->
1206 case newByteArray# (wORD_SCALE n#) s1# of { (# s2#, marr# #) ->
1207 (# s2#, STUArray l u marr# #) }}
1208 {-# INLINE unsafeRead #-}
1209 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1210 case readAddrArray# marr# i# s1# of { (# s2#, e# #) ->
1211 (# s2#, FunPtr e# #) }
1212 {-# INLINE unsafeWrite #-}
1213 unsafeWrite (STUArray _ _ marr#) (I# i#) (FunPtr e#) = ST $ \s1# ->
1214 case writeAddrArray# marr# i# e# s1# of { s2# ->
1217 instance MArray (STUArray s) Float (ST s) where
1218 {-# INLINE newArray_ #-}
1219 newArray_ (l,u) = ST $ \s1# ->
1220 case rangeSize (l,u) of { I# n# ->
1221 case newByteArray# (fLOAT_SCALE n#) s1# of { (# s2#, marr# #) ->
1222 (# s2#, STUArray l u marr# #) }}
1223 {-# INLINE unsafeRead #-}
1224 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1225 case readFloatArray# marr# i# s1# of { (# s2#, e# #) ->
1227 {-# INLINE unsafeWrite #-}
1228 unsafeWrite (STUArray _ _ marr#) (I# i#) (F# e#) = ST $ \s1# ->
1229 case writeFloatArray# marr# i# e# s1# of { s2# ->
1232 instance MArray (STUArray s) Double (ST s) where
1233 {-# INLINE newArray_ #-}
1234 newArray_ (l,u) = ST $ \s1# ->
1235 case rangeSize (l,u) of { I# n# ->
1236 case newByteArray# (dOUBLE_SCALE n#) s1# of { (# s2#, marr# #) ->
1237 (# s2#, STUArray l u marr# #) }}
1238 {-# INLINE unsafeRead #-}
1239 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1240 case readDoubleArray# marr# i# s1# of { (# s2#, e# #) ->
1242 {-# INLINE unsafeWrite #-}
1243 unsafeWrite (STUArray _ _ marr#) (I# i#) (D# e#) = ST $ \s1# ->
1244 case writeDoubleArray# marr# i# e# s1# of { s2# ->
1247 instance MArray (STUArray s) (StablePtr a) (ST s) where
1248 {-# INLINE newArray_ #-}
1249 newArray_ (l,u) = ST $ \s1# ->
1250 case rangeSize (l,u) of { I# n# ->
1251 case newByteArray# (wORD_SCALE n#) s1# of { (# s2#, marr# #) ->
1252 (# s2#, STUArray l u marr# #) }}
1253 {-# INLINE unsafeRead #-}
1254 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1255 case readStablePtrArray# marr# i# s1# of { (# s2#, e# #) ->
1256 (# s2# , StablePtr e# #) }
1257 {-# INLINE unsafeWrite #-}
1258 unsafeWrite (STUArray _ _ marr#) (I# i#) (StablePtr e#) = ST $ \s1# ->
1259 case writeStablePtrArray# marr# i# e# s1# of { s2# ->
1262 instance MArray (STUArray s) Int8 (ST s) where
1263 {-# INLINE newArray_ #-}
1264 newArray_ (l,u) = ST $ \s1# ->
1265 case rangeSize (l,u) of { I# n# ->
1266 case newByteArray# n# s1# of { (# s2#, marr# #) ->
1267 (# s2#, STUArray l u marr# #) }}
1268 {-# INLINE unsafeRead #-}
1269 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1270 case readInt8Array# marr# i# s1# of { (# s2#, e# #) ->
1272 {-# INLINE unsafeWrite #-}
1273 unsafeWrite (STUArray _ _ marr#) (I# i#) (I8# e#) = ST $ \s1# ->
1274 case writeInt8Array# marr# i# e# s1# of { s2# ->
1277 instance MArray (STUArray s) Int16 (ST s) where
1278 {-# INLINE newArray_ #-}
1279 newArray_ (l,u) = ST $ \s1# ->
1280 case rangeSize (l,u) of { I# n# ->
1281 case newByteArray# (n# *# 2#) s1# of { (# s2#, marr# #) ->
1282 (# s2#, STUArray l u marr# #) }}
1283 {-# INLINE unsafeRead #-}
1284 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1285 case readInt16Array# marr# i# s1# of { (# s2#, e# #) ->
1286 (# s2#, I16# e# #) }
1287 {-# INLINE unsafeWrite #-}
1288 unsafeWrite (STUArray _ _ marr#) (I# i#) (I16# e#) = ST $ \s1# ->
1289 case writeInt16Array# marr# i# e# s1# of { s2# ->
1292 instance MArray (STUArray s) Int32 (ST s) where
1293 {-# INLINE newArray_ #-}
1294 newArray_ (l,u) = ST $ \s1# ->
1295 case rangeSize (l,u) of { I# n# ->
1296 case newByteArray# (n# *# 4#) s1# of { (# s2#, marr# #) ->
1297 (# s2#, STUArray l u marr# #) }}
1298 {-# INLINE unsafeRead #-}
1299 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1300 case readInt32Array# marr# i# s1# of { (# s2#, e# #) ->
1301 (# s2#, I32# e# #) }
1302 {-# INLINE unsafeWrite #-}
1303 unsafeWrite (STUArray _ _ marr#) (I# i#) (I32# e#) = ST $ \s1# ->
1304 case writeInt32Array# marr# i# e# s1# of { s2# ->
1307 instance MArray (STUArray s) Int64 (ST s) where
1308 {-# INLINE newArray_ #-}
1309 newArray_ (l,u) = ST $ \s1# ->
1310 case rangeSize (l,u) of { I# n# ->
1311 case newByteArray# (n# *# 8#) s1# of { (# s2#, marr# #) ->
1312 (# s2#, STUArray l u marr# #) }}
1313 {-# INLINE unsafeRead #-}
1314 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1315 case readInt64Array# marr# i# s1# of { (# s2#, e# #) ->
1316 (# s2#, I64# e# #) }
1317 {-# INLINE unsafeWrite #-}
1318 unsafeWrite (STUArray _ _ marr#) (I# i#) (I64# e#) = ST $ \s1# ->
1319 case writeInt64Array# marr# i# e# s1# of { s2# ->
1322 instance MArray (STUArray s) Word8 (ST s) where
1323 {-# INLINE newArray_ #-}
1324 newArray_ (l,u) = ST $ \s1# ->
1325 case rangeSize (l,u) of { I# n# ->
1326 case newByteArray# n# s1# of { (# s2#, marr# #) ->
1327 (# s2#, STUArray l u marr# #) }}
1328 {-# INLINE unsafeRead #-}
1329 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1330 case readWord8Array# marr# i# s1# of { (# s2#, e# #) ->
1332 {-# INLINE unsafeWrite #-}
1333 unsafeWrite (STUArray _ _ marr#) (I# i#) (W8# e#) = ST $ \s1# ->
1334 case writeWord8Array# marr# i# e# s1# of { s2# ->
1337 instance MArray (STUArray s) Word16 (ST s) where
1338 {-# INLINE newArray_ #-}
1339 newArray_ (l,u) = ST $ \s1# ->
1340 case rangeSize (l,u) of { I# n# ->
1341 case newByteArray# (n# *# 2#) s1# of { (# s2#, marr# #) ->
1342 (# s2#, STUArray l u marr# #) }}
1343 {-# INLINE unsafeRead #-}
1344 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1345 case readWord16Array# marr# i# s1# of { (# s2#, e# #) ->
1346 (# s2#, W16# e# #) }
1347 {-# INLINE unsafeWrite #-}
1348 unsafeWrite (STUArray _ _ marr#) (I# i#) (W16# e#) = ST $ \s1# ->
1349 case writeWord16Array# marr# i# e# s1# of { s2# ->
1352 instance MArray (STUArray s) Word32 (ST s) where
1353 {-# INLINE newArray_ #-}
1354 newArray_ (l,u) = ST $ \s1# ->
1355 case rangeSize (l,u) of { I# n# ->
1356 case newByteArray# (n# *# 4#) s1# of { (# s2#, marr# #) ->
1357 (# s2#, STUArray l u marr# #) }}
1358 {-# INLINE unsafeRead #-}
1359 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1360 case readWord32Array# marr# i# s1# of { (# s2#, e# #) ->
1361 (# s2#, W32# e# #) }
1362 {-# INLINE unsafeWrite #-}
1363 unsafeWrite (STUArray _ _ marr#) (I# i#) (W32# e#) = ST $ \s1# ->
1364 case writeWord32Array# marr# i# e# s1# of { s2# ->
1367 instance MArray (STUArray s) Word64 (ST s) where
1368 {-# INLINE newArray_ #-}
1369 newArray_ (l,u) = ST $ \s1# ->
1370 case rangeSize (l,u) of { I# n# ->
1371 case newByteArray# (n# *# 8#) s1# of { (# s2#, marr# #) ->
1372 (# s2#, STUArray l u marr# #) }}
1373 {-# INLINE unsafeRead #-}
1374 unsafeRead (STUArray _ _ marr#) (I# i#) = ST $ \s1# ->
1375 case readWord64Array# marr# i# s1# of { (# s2#, e# #) ->
1376 (# s2#, W64# e# #) }
1377 {-# INLINE unsafeWrite #-}
1378 unsafeWrite (STUArray _ _ marr#) (I# i#) (W64# e#) = ST $ \s1# ->
1379 case writeWord64Array# marr# i# e# s1# of { s2# ->
1382 -----------------------------------------------------------------------------
1383 -- Translation between elements and bytes
1385 bOOL_SCALE, bOOL_WORD_SCALE,
1386 wORD_SCALE, dOUBLE_SCALE, fLOAT_SCALE :: Int# -> Int#
1387 bOOL_SCALE n# = (n# +# last#) `uncheckedIShiftRA#` 3#
1388 where I# last# = SIZEOF_HSWORD * 8 - 1
1389 bOOL_WORD_SCALE n# = bOOL_INDEX (n# +# last#)
1390 where I# last# = SIZEOF_HSWORD * 8 - 1
1391 wORD_SCALE n# = scale# *# n# where I# scale# = SIZEOF_HSWORD
1392 dOUBLE_SCALE n# = scale# *# n# where I# scale# = SIZEOF_HSDOUBLE
1393 fLOAT_SCALE n# = scale# *# n# where I# scale# = SIZEOF_HSFLOAT
1395 bOOL_INDEX :: Int# -> Int#
1396 #if SIZEOF_HSWORD == 4
1397 bOOL_INDEX i# = i# `uncheckedIShiftRA#` 5#
1398 #elif SIZEOF_HSWORD == 8
1399 bOOL_INDEX i# = i# `uncheckedIShiftRA#` 6#
1402 bOOL_BIT, bOOL_NOT_BIT :: Int# -> Word#
1403 bOOL_BIT n# = int2Word# 1# `uncheckedShiftL#` (word2Int# (int2Word# n# `and#` mask#))
1404 where W# mask# = SIZEOF_HSWORD * 8 - 1
1405 bOOL_NOT_BIT n# = bOOL_BIT n# `xor#` mb# where W# mb# = maxBound
1406 #endif /* __GLASGOW_HASKELL__ */
1409 newMBArray_ :: (Ix i, Storable e) => (i,i) -> ST s (STUArray s i e)
1410 newMBArray_ = makeArray undefined
1412 makeArray :: (Ix i, Storable e) => e -> (i,i) -> ST s (STUArray s i e)
1413 makeArray dummy (l,u) = do
1414 marr <- newMutableByteArray (rangeSize (l,u) * sizeOf dummy)
1415 return (STUArray l u marr)
1417 unsafeReadMBArray :: Storable e => STUArray s i e -> Int -> ST s e
1418 unsafeReadMBArray (STUArray _ _ marr) = readMutableByteArray marr
1420 unsafeWriteMBArray :: Storable e => STUArray s i e -> Int -> e -> ST s ()
1421 unsafeWriteMBArray (STUArray _ _ marr) = writeMutableByteArray marr
1423 instance MArray (STUArray s) Bool (ST s) where
1424 newArray_ (l,u) = do
1425 marr <- newMutableByteArray (bOOL_SCALE (rangeSize (l,u)))
1426 return (STUArray l u marr)
1427 unsafeRead (STUArray _ _ marr) i = do
1428 let ix = bOOL_INDEX i
1429 bit = bOOL_SUBINDEX i
1430 w <- readMutableByteArray marr ix
1431 return (testBit (w::BitSet) bit)
1432 unsafeWrite (STUArray _ _ marr) i e = do
1433 let ix = bOOL_INDEX i
1434 bit = bOOL_SUBINDEX i
1435 w <- readMutableByteArray marr ix
1436 writeMutableByteArray marr ix
1437 (if e then setBit (w::BitSet) bit else clearBit w bit)
1439 instance MArray (STUArray s) Char (ST s) where
1440 newArray_ = newMBArray_
1441 unsafeRead = unsafeReadMBArray
1442 unsafeWrite = unsafeWriteMBArray
1444 instance MArray (STUArray s) Int (ST s) where
1445 newArray_ = newMBArray_
1446 unsafeRead = unsafeReadMBArray
1447 unsafeWrite = unsafeWriteMBArray
1449 instance MArray (STUArray s) Word (ST s) where
1450 newArray_ = newMBArray_
1451 unsafeRead = unsafeReadMBArray
1452 unsafeWrite = unsafeWriteMBArray
1454 instance MArray (STUArray s) (Ptr a) (ST s) where
1455 newArray_ = newMBArray_
1456 unsafeRead = unsafeReadMBArray
1457 unsafeWrite = unsafeWriteMBArray
1459 instance MArray (STUArray s) (FunPtr a) (ST s) where
1460 newArray_ = newMBArray_
1461 unsafeRead = unsafeReadMBArray
1462 unsafeWrite = unsafeWriteMBArray
1464 instance MArray (STUArray s) Float (ST s) where
1465 newArray_ = newMBArray_
1466 unsafeRead = unsafeReadMBArray
1467 unsafeWrite = unsafeWriteMBArray
1469 instance MArray (STUArray s) Double (ST s) where
1470 newArray_ = newMBArray_
1471 unsafeRead = unsafeReadMBArray
1472 unsafeWrite = unsafeWriteMBArray
1474 instance MArray (STUArray s) (StablePtr a) (ST s) where
1475 newArray_ = newMBArray_
1476 unsafeRead = unsafeReadMBArray
1477 unsafeWrite = unsafeWriteMBArray
1479 instance MArray (STUArray s) Int8 (ST s) where
1480 newArray_ = newMBArray_
1481 unsafeRead = unsafeReadMBArray
1482 unsafeWrite = unsafeWriteMBArray
1484 instance MArray (STUArray s) Int16 (ST s) where
1485 newArray_ = newMBArray_
1486 unsafeRead = unsafeReadMBArray
1487 unsafeWrite = unsafeWriteMBArray
1489 instance MArray (STUArray s) Int32 (ST s) where
1490 newArray_ = newMBArray_
1491 unsafeRead = unsafeReadMBArray
1492 unsafeWrite = unsafeWriteMBArray
1494 instance MArray (STUArray s) Int64 (ST s) where
1495 newArray_ = newMBArray_
1496 unsafeRead = unsafeReadMBArray
1497 unsafeWrite = unsafeWriteMBArray
1499 instance MArray (STUArray s) Word8 (ST s) where
1500 newArray_ = newMBArray_
1501 unsafeRead = unsafeReadMBArray
1502 unsafeWrite = unsafeWriteMBArray
1504 instance MArray (STUArray s) Word16 (ST s) where
1505 newArray_ = newMBArray_
1506 unsafeRead = unsafeReadMBArray
1507 unsafeWrite = unsafeWriteMBArray
1509 instance MArray (STUArray s) Word32 (ST s) where
1510 newArray_ = newMBArray_
1511 unsafeRead = unsafeReadMBArray
1512 unsafeWrite = unsafeWriteMBArray
1514 instance MArray (STUArray s) Word64 (ST s) where
1515 newArray_ = newMBArray_
1516 unsafeRead = unsafeReadMBArray
1517 unsafeWrite = unsafeWriteMBArray
1521 bitSetSize = bitSize (0::BitSet)
1523 bOOL_SCALE :: Int -> Int
1524 bOOL_SCALE n = (n + bitSetSize - 1) `div` bitSetSize
1526 bOOL_INDEX :: Int -> Int
1527 bOOL_INDEX i = i `div` bitSetSize
1529 bOOL_SUBINDEX :: Int -> Int
1530 bOOL_SUBINDEX i = i `mod` bitSetSize
1531 #endif /* __HUGS__ */
1533 -----------------------------------------------------------------------------
1536 -- | Converts a mutable array (any instance of 'MArray') to an
1537 -- immutable array (any instance of 'IArray') by taking a complete
1539 freeze :: (Ix i, MArray a e m, IArray b e) => a i e -> m (b i e)
1540 freeze marr = case bounds marr of
1542 ies <- sequence [do e <- unsafeRead marr i; return (i,e)
1543 | i <- [0 .. rangeSize (l,u) - 1]]
1544 return (unsafeArray (l,u) ies)
1546 #ifdef __GLASGOW_HASKELL__
1547 freezeSTUArray :: Ix i => STUArray s i e -> ST s (UArray i e)
1548 freezeSTUArray (STUArray l u marr#) = ST $ \s1# ->
1549 case sizeofMutableByteArray# marr# of { n# ->
1550 case newByteArray# n# s1# of { (# s2#, marr'# #) ->
1551 case unsafeCoerce# memcpy marr'# marr# n# s2# of { (# s3#, () #) ->
1552 case unsafeFreezeByteArray# marr'# s3# of { (# s4#, arr# #) ->
1553 (# s4#, UArray l u arr# #) }}}}
1556 "freeze/STArray" freeze = ArrST.freezeSTArray
1557 "freeze/STUArray" freeze = freezeSTUArray
1559 #endif /* __GLASGOW_HASKELL__ */
1561 -- In-place conversion of mutable arrays to immutable ones places
1562 -- a proof obligation on the user: no other parts of your code can
1563 -- have a reference to the array at the point where you unsafely
1564 -- freeze it (and, subsequently mutate it, I suspect).
1567 Converts an mutable array into an immutable array. The
1568 implementation may either simply cast the array from
1569 one type to the other without copying the array, or it
1570 may take a full copy of the array.
1572 Note that because the array is possibly not copied, any subsequent
1573 modifications made to the mutable version of the array may be
1574 shared with the immutable version. It is safe to use, therefore, if
1575 the mutable version is never modified after the freeze operation.
1577 The non-copying implementation is supported between certain pairs
1578 of array types only; one constraint is that the array types must
1579 have identical representations. In GHC, The following pairs of
1580 array types have a non-copying O(1) implementation of
1581 'unsafeFreeze'. Because the optimised versions are enabled by
1582 specialisations, you will need to compile with optimisation (-O) to
1585 * 'Data.Array.IO.IOUArray' -> 'Data.Array.Unboxed.UArray'
1587 * 'Data.Array.ST.STUArray' -> 'Data.Array.Unboxed.UArray'
1589 * 'Data.Array.IO.IOArray' -> 'Data.Array.Array'
1591 * 'Data.Array.ST.STArray' -> 'Data.Array.Array'
1593 {-# INLINE unsafeFreeze #-}
1594 unsafeFreeze :: (Ix i, MArray a e m, IArray b e) => a i e -> m (b i e)
1595 unsafeFreeze = freeze
1598 "unsafeFreeze/STArray" unsafeFreeze = ArrST.unsafeFreezeSTArray
1599 "unsafeFreeze/STUArray" unsafeFreeze = unsafeFreezeSTUArray
1602 -----------------------------------------------------------------------------
1605 -- | Converts an immutable array (any instance of 'IArray') into a
1606 -- mutable array (any instance of 'MArray') by taking a complete copy
1608 thaw :: (Ix i, IArray a e, MArray b e m) => a i e -> m (b i e)
1609 thaw arr = case bounds arr of
1611 marr <- newArray_ (l,u)
1612 sequence_ [unsafeWrite marr i (unsafeAt arr i)
1613 | i <- [0 .. rangeSize (l,u) - 1]]
1616 #ifdef __GLASGOW_HASKELL__
1617 thawSTUArray :: Ix i => UArray i e -> ST s (STUArray s i e)
1618 thawSTUArray (UArray l u arr#) = ST $ \s1# ->
1619 case sizeofByteArray# arr# of { n# ->
1620 case newByteArray# n# s1# of { (# s2#, marr# #) ->
1621 case unsafeCoerce# memcpy marr# arr# n# s2# of { (# s3#, () #) ->
1622 (# s3#, STUArray l u marr# #) }}}
1624 foreign import ccall unsafe "memcpy"
1625 memcpy :: MutableByteArray# RealWorld -> ByteArray# -> Int# -> IO ()
1628 "thaw/STArray" thaw = ArrST.thawSTArray
1629 "thaw/STUArray" thaw = thawSTUArray
1631 #endif /* __GLASGOW_HASKELL__ */
1634 thawSTUArray :: Ix i => UArray i e -> ST s (STUArray s i e)
1635 thawSTUArray (UArray l u arr) = do
1636 marr <- thawByteArray arr
1637 return (STUArray l u marr)
1640 -- In-place conversion of immutable arrays to mutable ones places
1641 -- a proof obligation on the user: no other parts of your code can
1642 -- have a reference to the array at the point where you unsafely
1643 -- thaw it (and, subsequently mutate it, I suspect).
1646 Converts an immutable array into a mutable array. The
1647 implementation may either simply cast the array from
1648 one type to the other without copying the array, or it
1649 may take a full copy of the array.
1651 Note that because the array is possibly not copied, any subsequent
1652 modifications made to the mutable version of the array may be
1653 shared with the immutable version. It is safe to use, therefore, if
1654 the immutable version is never referenced again.
1656 The non-copying implementation is supported between certain pairs
1657 of array types only; one constraint is that the array types must
1658 have identical representations. In GHC, The following pairs of
1659 array types have a non-copying O(1) implementation of
1660 'unsafeFreeze'. Because the optimised versions are enabled by
1661 specialisations, you will need to compile with optimisation (-O) to
1664 * 'Data.Array.Unboxed.UArray' -> 'Data.Array.IO.IOUArray'
1666 * 'Data.Array.Unboxed.UArray' -> 'Data.Array.ST.STUArray'
1668 * 'Data.Array.Array' -> 'Data.Array.IO.IOArray'
1670 * 'Data.Array.Array' -> 'Data.Array.ST.STArray'
1672 {-# INLINE unsafeThaw #-}
1673 unsafeThaw :: (Ix i, IArray a e, MArray b e m) => a i e -> m (b i e)
1676 #ifdef __GLASGOW_HASKELL__
1677 {-# INLINE unsafeThawSTUArray #-}
1678 unsafeThawSTUArray :: Ix i => UArray i e -> ST s (STUArray s i e)
1679 unsafeThawSTUArray (UArray l u marr#) =
1680 return (STUArray l u (unsafeCoerce# marr#))
1683 "unsafeThaw/STArray" unsafeThaw = ArrST.unsafeThawSTArray
1684 "unsafeThaw/STUArray" unsafeThaw = unsafeThawSTUArray
1686 #endif /* __GLASGOW_HASKELL__ */
1688 -- | Casts an 'STUArray' with one element type into one with a
1689 -- different element type. All the elements of the resulting array
1690 -- are undefined (unless you know what you\'re doing...).
1692 #ifdef __GLASGOW_HASKELL__
1693 castSTUArray :: STUArray s ix a -> ST s (STUArray s ix b)
1694 castSTUArray (STUArray l u marr#) = return (STUArray l u marr#)
1698 castSTUArray :: STUArray s ix a -> ST s (STUArray s ix b)
1699 castSTUArray (STUArray l u marr) = return (STUArray l u marr)