stellar-veritas/bundled/Basement/BoxedArray.hs
2026-01-25 02:27:22 +01:00

781 lines
25 KiB
Haskell

{-# LANGUAGE BangPatterns #-}
{-# LANGUAGE DeriveDataTypeable #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE RebindableSyntax #-}
{-# LANGUAGE NoImplicitPrelude #-}
-- |
-- Module : Basement.BoxedArray
-- License : BSD-style
-- Maintainer : Vincent Hanquez <vincent@snarc.org>
-- Stability : experimental
-- Portability : portable
--
-- Simple boxed array abstraction
--
{-# LANGUAGE MagicHash #-}
{-# LANGUAGE BangPatterns #-}
{-# LANGUAGE UnboxedTuples #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE TypeOperators #-}
module Basement.BoxedArray
( Array
, MArray
, empty
, length
, mutableLength
, copy
, unsafeCopyAtRO
, thaw
, new
, create
, unsafeFreeze
, unsafeThaw
, freeze
, unsafeWrite
, unsafeRead
, unsafeIndex
, write
, read
, index
, singleton
, replicate
, null
, take
, drop
, splitAt
, revTake
, revDrop
, revSplitAt
, splitOn
, sub
, intersperse
, span
, spanEnd
, break
, breakEnd
, mapFromUnboxed
, mapToUnboxed
, cons
, snoc
, uncons
, unsnoc
-- , findIndex
, sortBy
, filter
, reverse
, elem
, find
, foldl'
, foldr
, foldl1'
, foldr1
, all
, any
, isPrefixOf
, isSuffixOf
, builderAppend
, builderBuild
, builderBuild_
) where
import GHC.Prim
import GHC.Types
import GHC.ST
import Data.Proxy
import Basement.Numerical.Additive
import Basement.Numerical.Subtractive
import Basement.NonEmpty
import Basement.Compat.Base
import qualified Basement.Alg.Class as Alg
import qualified Basement.Alg.Mutable as Alg
import Basement.Compat.MonadTrans
import Basement.Compat.Semigroup
import Basement.Compat.Primitive
import Basement.Types.OffsetSize
import Basement.PrimType
import Basement.NormalForm
import Basement.Monad
import Basement.UArray.Base (UArray)
import qualified Basement.UArray.Base as UArray
import Basement.Exception
import Basement.MutableBuilder
import qualified Basement.Compat.ExtList as List
-- | Array of a
data Array a = Array {-# UNPACK #-} !(Offset a)
{-# UNPACK #-} !(CountOf a)
(Array# a)
deriving (Typeable)
instance Data ty => Data (Array ty) where
dataTypeOf _ = arrayType
toConstr _ = error "toConstr"
gunfold _ _ = error "gunfold"
arrayType :: DataType
arrayType = mkNoRepType "Foundation.Array"
instance NormalForm a => NormalForm (Array a) where
toNormalForm arr = loop 0
where
!sz = length arr
loop !i
| i .==# sz = ()
| otherwise = unsafeIndex arr i `seq` loop (i+1)
-- | Mutable Array of a
data MArray a st = MArray {-# UNPACK #-} !(Offset a)
{-# UNPACK #-} !(CountOf a)
(MutableArray# st a)
deriving (Typeable)
instance Functor Array where
fmap = map
instance Semigroup (Array a) where
(<>) = append
instance Monoid (Array a) where
mempty = empty
mconcat = concat
instance Show a => Show (Array a) where
show v = show (toList v)
instance Eq a => Eq (Array a) where
(==) = equal
instance Ord a => Ord (Array a) where
compare = vCompare
instance IsList (Array ty) where
type Item (Array ty) = ty
fromList = vFromList
fromListN len = vFromListN (CountOf len)
toList = vToList
-- | return the numbers of elements in a mutable array
mutableLength :: MArray ty st -> Int
mutableLength (MArray _ (CountOf len) _) = len
{-# INLINE mutableLength #-}
-- | return the numbers of elements in a mutable array
mutableLengthSize :: MArray ty st -> CountOf ty
mutableLengthSize (MArray _ size _) = size
{-# INLINE mutableLengthSize #-}
-- | Return the element at a specific index from an array.
--
-- If the index @n is out of bounds, an error is raised.
index :: Array ty -> Offset ty -> ty
index array n
| isOutOfBound n len = outOfBound OOB_Index n len
| otherwise = unsafeIndex array n
where len = length array
{-# INLINE index #-}
-- | Return the element at a specific index from an array without bounds checking.
--
-- Reading from invalid memory can return unpredictable and invalid values.
-- use 'index' if unsure.
unsafeIndex :: Array ty -> Offset ty -> ty
unsafeIndex (Array start _ a) ofs = primArrayIndex a (start+ofs)
{-# INLINE unsafeIndex #-}
-- | read a cell in a mutable array.
--
-- If the index is out of bounds, an error is raised.
read :: PrimMonad prim => MArray ty (PrimState prim) -> Offset ty -> prim ty
read array n
| isOutOfBound n len = primOutOfBound OOB_Read n len
| otherwise = unsafeRead array n
where len = mutableLengthSize array
{-# INLINE read #-}
-- | read from a cell in a mutable array without bounds checking.
--
-- Reading from invalid memory can return unpredictable and invalid values.
-- use 'read' if unsure.
unsafeRead :: PrimMonad prim => MArray ty (PrimState prim) -> Offset ty -> prim ty
unsafeRead (MArray start _ ma) i = primMutableArrayRead ma (start + i)
{-# INLINE unsafeRead #-}
-- | Write to a cell in a mutable array.
--
-- If the index is out of bounds, an error is raised.
write :: PrimMonad prim => MArray ty (PrimState prim) -> Offset ty -> ty -> prim ()
write array n val
| isOutOfBound n len = primOutOfBound OOB_Write n len
| otherwise = unsafeWrite array n val
where len = mutableLengthSize array
{-# INLINE write #-}
-- | write to a cell in a mutable array without bounds checking.
--
-- Writing with invalid bounds will corrupt memory and your program will
-- become unreliable. use 'write' if unsure.
unsafeWrite :: PrimMonad prim => MArray ty (PrimState prim) -> Offset ty -> ty -> prim ()
unsafeWrite (MArray start _ ma) ofs v =
primMutableArrayWrite ma (start + ofs) v
{-# INLINE unsafeWrite #-}
-- | Freeze a mutable array into an array.
--
-- the MArray must not be changed after freezing.
unsafeFreeze :: PrimMonad prim => MArray ty (PrimState prim) -> prim (Array ty)
unsafeFreeze (MArray ofs sz ma) = primitive $ \s1 ->
case unsafeFreezeArray# ma s1 of
(# s2, a #) -> (# s2, Array ofs sz a #)
{-# INLINE unsafeFreeze #-}
-- | Thaw an immutable array.
--
-- The Array must not be used after thawing.
unsafeThaw :: PrimMonad prim => Array ty -> prim (MArray ty (PrimState prim))
unsafeThaw (Array ofs sz a) = primitive $ \st -> (# st, MArray ofs sz (unsafeCoerce# a) #)
{-# INLINE unsafeThaw #-}
-- | Thaw an array to a mutable array.
--
-- the array is not modified, instead a new mutable array is created
-- and every values is copied, before returning the mutable array.
thaw :: PrimMonad prim => Array ty -> prim (MArray ty (PrimState prim))
thaw array = do
m <- new (length array)
unsafeCopyAtRO m (Offset 0) array (Offset 0) (length array)
pure m
{-# INLINE thaw #-}
freeze :: PrimMonad prim => MArray ty (PrimState prim) -> prim (Array ty)
freeze marray = do
m <- new sz
copyAt m (Offset 0) marray (Offset 0) sz
unsafeFreeze m
where
sz = mutableLengthSize marray
-- | Copy the element to a new element array
copy :: Array ty -> Array ty
copy a = runST (unsafeThaw a >>= freeze)
-- | Copy a number of elements from an array to another array with offsets
copyAt :: PrimMonad prim
=> MArray ty (PrimState prim) -- ^ destination array
-> Offset ty -- ^ offset at destination
-> MArray ty (PrimState prim) -- ^ source array
-> Offset ty -- ^ offset at source
-> CountOf ty -- ^ number of elements to copy
-> prim ()
copyAt dst od src os n = loop od os
where -- !endIndex = os `offsetPlusE` n
loop d s
| s .==# n = pure ()
| otherwise = unsafeRead src s >>= unsafeWrite dst d >> loop (d+1) (s+1)
-- | Copy @n@ sequential elements from the specified offset in a source array
-- to the specified position in a destination array.
--
-- This function does not check bounds. Accessing invalid memory can return
-- unpredictable and invalid values.
unsafeCopyAtRO :: PrimMonad prim
=> MArray ty (PrimState prim) -- ^ destination array
-> Offset ty -- ^ offset at destination
-> Array ty -- ^ source array
-> Offset ty -- ^ offset at source
-> CountOf ty -- ^ number of elements to copy
-> prim ()
unsafeCopyAtRO (MArray (Offset (I# dstart)) _ da) (Offset (I# dofs))
(Array (Offset (I# sstart)) _ sa) (Offset (I# sofs))
(CountOf (I# n)) =
primitive $ \st ->
(# copyArray# sa (sstart +# sofs) da (dstart +# dofs) n st, () #)
-- | Allocate a new array with a fill function that has access to the elements of
-- the source array.
unsafeCopyFrom :: Array ty -- ^ Source array
-> CountOf ty -- ^ Length of the destination array
-> (Array ty -> Offset ty -> MArray ty s -> ST s ())
-- ^ Function called for each element in the source array
-> ST s (Array ty) -- ^ Returns the filled new array
unsafeCopyFrom v' newLen f = new newLen >>= fill (Offset 0) f >>= unsafeFreeze
where len = length v'
endIdx = Offset 0 `offsetPlusE` len
fill i f' r'
| i == endIdx = pure r'
| otherwise = do f' v' i r'
fill (i + Offset 1) f' r'
-- | Create a new mutable array of size @n.
--
-- all the cells are uninitialized and could contains invalid values.
--
-- All mutable arrays are allocated on a 64 bits aligned addresses
-- and always contains a number of bytes multiples of 64 bits.
new :: PrimMonad prim => CountOf ty -> prim (MArray ty (PrimState prim))
new sz@(CountOf (I# n)) = primitive $ \s1 ->
case newArray# n (error "vector: internal error uninitialized vector") s1 of
(# s2, ma #) -> (# s2, MArray (Offset 0) sz ma #)
-- | Create a new array of size @n by settings each cells through the
-- function @f.
create :: forall ty . CountOf ty -- ^ the size of the array
-> (Offset ty -> ty) -- ^ the function that set the value at the index
-> Array ty -- ^ the array created
create n initializer = runST (new n >>= iter initializer)
where
iter :: PrimMonad prim => (Offset ty -> ty) -> MArray ty (PrimState prim) -> prim (Array ty)
iter f ma = loop 0
where
loop s
| s .==# n = unsafeFreeze ma
| otherwise = unsafeWrite ma s (f s) >> loop (s+1)
{-# INLINE loop #-}
{-# INLINE iter #-}
-----------------------------------------------------------------------
-- higher level collection implementation
-----------------------------------------------------------------------
equal :: Eq a => Array a -> Array a -> Bool
equal a b = (len == length b) && eachEqual 0
where
len = length a
eachEqual !i
| i .==# len = True
| unsafeIndex a i /= unsafeIndex b i = False
| otherwise = eachEqual (i+1)
vCompare :: Ord a => Array a -> Array a -> Ordering
vCompare a b = loop 0
where
!la = length a
!lb = length b
loop n
| n .==# la = if la == lb then EQ else LT
| n .==# lb = GT
| otherwise =
case unsafeIndex a n `compare` unsafeIndex b n of
EQ -> loop (n+1)
r -> r
empty :: Array a
empty = runST $ onNewArray 0 (\_ s -> s)
length :: Array a -> CountOf a
length (Array _ sz _) = sz
vFromList :: [a] -> Array a
vFromList l = runST (new len >>= loop 0 l)
where
len = List.length l
loop _ [] ma = unsafeFreeze ma
loop i (x:xs) ma = unsafeWrite ma i x >> loop (i+1) xs ma
-- | just like vFromList but with a length hint.
--
-- The resulting array is guarantee to have been allocated to the length
-- specified, but the slice might point to the initialized cells only in
-- case the length is bigger than the list.
--
-- If the length is too small, then the list is truncated.
--
vFromListN :: forall a . CountOf a -> [a] -> Array a
vFromListN len l = runST $ do
ma <- new len
sz <- loop 0 l ma
unsafeFreezeShrink ma sz
where
-- TODO rewrite without ma as parameter
loop :: Offset a -> [a] -> MArray a s -> ST s (CountOf a)
loop i [] _ = return (offsetAsSize i)
loop i (x:xs) ma
| i .==# len = return (offsetAsSize i)
| otherwise = unsafeWrite ma i x >> loop (i+1) xs ma
vToList :: Array a -> [a]
vToList v
| len == 0 = []
| otherwise = fmap (unsafeIndex v) [0..sizeLastOffset len]
where !len = length v
-- | Append 2 arrays together by creating a new bigger array
append :: Array ty -> Array ty -> Array ty
append a b = runST $ do
r <- new (la+lb)
unsafeCopyAtRO r (Offset 0) a (Offset 0) la
unsafeCopyAtRO r (sizeAsOffset la) b (Offset 0) lb
unsafeFreeze r
where la = length a
lb = length b
concat :: [Array ty] -> Array ty
concat l = runST $ do
r <- new (mconcat $ fmap length l)
loop r (Offset 0) l
unsafeFreeze r
where loop _ _ [] = pure ()
loop r i (x:xs) = do
unsafeCopyAtRO r i x (Offset 0) lx
loop r (i `offsetPlusE` lx) xs
where lx = length x
{-
modify :: PrimMonad m
=> Array a
-> (MArray (PrimState m) a -> m ())
-> m (Array a)
modify (Array a) f = primitive $ \st -> do
case thawArray# a 0# (sizeofArray# a) st of
(# st2, mv #) ->
case internal_ (f $ MArray mv) st2 of
st3 ->
case unsafeFreezeArray# mv st3 of
(# st4, a' #) -> (# st4, Array a' #)
-}
-----------------------------------------------------------------------
-- helpers
onNewArray :: PrimMonad m
=> Int
-> (MutableArray# (PrimState m) a -> State# (PrimState m) -> State# (PrimState m))
-> m (Array a)
onNewArray len@(I# len#) f = primitive $ \st -> do
case newArray# len# (error "onArray") st of { (# st2, mv #) ->
case f mv st2 of { st3 ->
case unsafeFreezeArray# mv st3 of { (# st4, a #) ->
(# st4, Array (Offset 0) (CountOf len) a #) }}}
-----------------------------------------------------------------------
null :: Array ty -> Bool
null = (==) 0 . length
take :: CountOf ty -> Array ty -> Array ty
take nbElems a@(Array start len arr)
| nbElems <= 0 = empty
| n == len = a
| otherwise = Array start n arr
where
n = min nbElems len
drop :: CountOf ty -> Array ty -> Array ty
drop nbElems a@(Array start len arr)
| nbElems <= 0 = a
| Just nbTails <- len - nbElems, nbTails > 0 = Array (start `offsetPlusE` nbElems) nbTails arr
| otherwise = empty
splitAt :: CountOf ty -> Array ty -> (Array ty, Array ty)
splitAt nbElems a@(Array start len arr)
| nbElems <= 0 = (empty, a)
| Just nbTails <- len - nbElems, nbTails > 0 = ( Array start nbElems arr
, Array (start `offsetPlusE` nbElems) nbTails arr)
| otherwise = (a, empty)
-- inverse a CountOf that is specified from the end (e.g. take n elements from the end)
countFromStart :: Array ty -> CountOf ty -> CountOf ty
countFromStart v sz@(CountOf sz')
| sz >= len = CountOf 0
| otherwise = CountOf (len' - sz')
where len@(CountOf len') = length v
revTake :: CountOf ty -> Array ty -> Array ty
revTake n v = drop (countFromStart v n) v
revDrop :: CountOf ty -> Array ty -> Array ty
revDrop n v = take (countFromStart v n) v
revSplitAt :: CountOf ty -> Array ty -> (Array ty, Array ty)
revSplitAt n v = (drop idx v, take idx v) where idx = countFromStart v n
splitOn :: (ty -> Bool) -> Array ty -> [Array ty]
splitOn predicate vec
| len == CountOf 0 = [mempty]
| otherwise = loop (Offset 0) (Offset 0)
where
!len = length vec
!endIdx = Offset 0 `offsetPlusE` len
loop prevIdx idx
| idx == endIdx = [sub vec prevIdx idx]
| otherwise =
let e = unsafeIndex vec idx
idx' = idx + 1
in if predicate e
then sub vec prevIdx idx : loop idx' idx'
else loop prevIdx idx'
sub :: Array ty -> Offset ty -> Offset ty -> Array ty
sub (Array start len a) startIdx expectedEndIdx
| startIdx == endIdx = empty
| otherwise = Array (start + startIdx) newLen a
where
newLen = endIdx - startIdx
endIdx = min expectedEndIdx (sizeAsOffset len)
break :: (ty -> Bool) -> Array ty -> (Array ty, Array ty)
break predicate v = findBreak 0
where
!len = length v
findBreak i
| i .==# len = (v, empty)
| otherwise =
if predicate (unsafeIndex v i)
then splitAt (offsetAsSize i) v
else findBreak (i+1)
breakEnd :: (ty -> Bool) -> Array ty -> (Array ty, Array ty)
breakEnd predicate v = findBreak (sizeAsOffset len)
where
!len = length v
findBreak !i
| i == 0 = (v, empty)
| predicate e = splitAt (offsetAsSize i) v
| otherwise = findBreak i'
where
e = unsafeIndex v i'
i' = i `offsetSub` 1
intersperse :: ty -> Array ty -> Array ty
intersperse sep v = case len - 1 of
Nothing -> v
Just 0 -> v
Just more -> runST $ unsafeCopyFrom v (len + more) (go (Offset 0 `offsetPlusE` more) sep)
where len = length v
-- terminate 1 before the end
go :: Offset ty -> ty -> Array ty -> Offset ty -> MArray ty s -> ST s ()
go endI sep' oldV oldI newV
| oldI == endI = unsafeWrite newV dst e
| otherwise = do
unsafeWrite newV dst e
unsafeWrite newV (dst + 1) sep'
where
e = unsafeIndex oldV oldI
dst = oldI + oldI
span :: (ty -> Bool) -> Array ty -> (Array ty, Array ty)
span p = break (not . p)
spanEnd :: (ty -> Bool) -> Array ty -> (Array ty, Array ty)
spanEnd p = breakEnd (not . p)
map :: (a -> b) -> Array a -> Array b
map f a = create (sizeCast Proxy $ length a) (\i -> f $ unsafeIndex a (offsetCast Proxy i))
mapFromUnboxed :: PrimType a => (a -> b) -> UArray a -> Array b
mapFromUnboxed f arr = vFromListN (sizeCast Proxy $ UArray.length arr) . fmap f . toList $ arr
mapToUnboxed :: PrimType b => (a -> b) -> Array a -> UArray b
mapToUnboxed f arr = UArray.vFromListN (sizeCast Proxy $ length arr) . fmap f . toList $ arr
{-
mapIndex :: (Int -> a -> b) -> Array a -> Array b
mapIndex f a = create (length a) (\i -> f i $ unsafeIndex a i)
-}
singleton :: ty -> Array ty
singleton e = runST $ do
a <- new 1
unsafeWrite a 0 e
unsafeFreeze a
replicate :: CountOf ty -> ty -> Array ty
replicate sz ty = create sz (const ty)
cons :: ty -> Array ty -> Array ty
cons e vec
| len == CountOf 0 = singleton e
| otherwise = runST $ do
mv <- new (len + CountOf 1)
unsafeWrite mv 0 e
unsafeCopyAtRO mv (Offset 1) vec (Offset 0) len
unsafeFreeze mv
where
!len = length vec
snoc :: Array ty -> ty -> Array ty
snoc vec e
| len == 0 = singleton e
| otherwise = runST $ do
mv <- new (len + 1)
unsafeCopyAtRO mv 0 vec 0 len
unsafeWrite mv (sizeAsOffset len) e
unsafeFreeze mv
where
!len = length vec
uncons :: Array ty -> Maybe (ty, Array ty)
uncons vec
| len == 0 = Nothing
| otherwise = Just (unsafeIndex vec 0, drop 1 vec)
where
!len = length vec
unsnoc :: Array ty -> Maybe (Array ty, ty)
unsnoc vec = case len - 1 of
Nothing -> Nothing
Just newLen -> Just (take newLen vec, unsafeIndex vec (sizeLastOffset len))
where
!len = length vec
elem :: Eq ty => ty -> Array ty -> Bool
elem !ty arr = loop 0
where
!sz = length arr
loop !i | i .==# sz = False
| t == ty = True
| otherwise = loop (i+1)
where t = unsafeIndex arr i
find :: (ty -> Bool) -> Array ty -> Maybe ty
find predicate vec = loop 0
where
!len = length vec
loop i
| i .==# len = Nothing
| otherwise =
let e = unsafeIndex vec i
in if predicate e then Just e else loop (i+1)
instance (PrimMonad prim, st ~ PrimState prim)
=> Alg.RandomAccess (MArray ty st) prim ty where
read (MArray _ _ mba) = primMutableArrayRead mba
write (MArray _ _ mba) = primMutableArrayWrite mba
sortBy :: forall ty . (ty -> ty -> Ordering) -> Array ty -> Array ty
sortBy xford vec
| len == 0 = empty
| otherwise = runST (thaw vec >>= doSort xford)
where
len = length vec
doSort :: PrimMonad prim => (ty -> ty -> Ordering) -> MArray ty (PrimState prim) -> prim (Array ty)
doSort ford ma = Alg.inplaceSortBy ford 0 len ma >> unsafeFreeze ma
filter :: forall ty . (ty -> Bool) -> Array ty -> Array ty
filter predicate vec = runST (new len >>= copyFilterFreeze predicate (unsafeIndex vec))
where
!len = length vec
copyFilterFreeze :: PrimMonad prim => (ty -> Bool) -> (Offset ty -> ty) -> MArray ty (PrimState prim) -> prim (Array ty)
copyFilterFreeze predi getVec mvec = loop (Offset 0) (Offset 0) >>= freezeUntilIndex mvec
where
loop d s
| s .==# len = pure d
| predi v = unsafeWrite mvec d v >> loop (d+1) (s+1)
| otherwise = loop d (s+1)
where
v = getVec s
freezeUntilIndex :: PrimMonad prim => MArray ty (PrimState prim) -> Offset ty -> prim (Array ty)
freezeUntilIndex mvec d = do
m <- new (offsetAsSize d)
copyAt m (Offset 0) mvec (Offset 0) (offsetAsSize d)
unsafeFreeze m
unsafeFreezeShrink :: PrimMonad prim => MArray ty (PrimState prim) -> CountOf ty -> prim (Array ty)
unsafeFreezeShrink (MArray start _ ma) n = unsafeFreeze (MArray start n ma)
reverse :: Array ty -> Array ty
reverse a = create len toEnd
where
len@(CountOf s) = length a
toEnd (Offset i) = unsafeIndex a (Offset (s - 1 - i))
foldr :: (ty -> a -> a) -> a -> Array ty -> a
foldr f initialAcc vec = loop 0
where
len = length vec
loop !i
| i .==# len = initialAcc
| otherwise = unsafeIndex vec i `f` loop (i+1)
foldl' :: (a -> ty -> a) -> a -> Array ty -> a
foldl' f initialAcc vec = loop 0 initialAcc
where
len = length vec
loop !i !acc
| i .==# len = acc
| otherwise = loop (i+1) (f acc (unsafeIndex vec i))
foldl1' :: (ty -> ty -> ty) -> NonEmpty (Array ty) -> ty
foldl1' f arr = let (initialAcc, rest) = splitAt 1 $ getNonEmpty arr
in foldl' f (unsafeIndex initialAcc 0) rest
foldr1 :: (ty -> ty -> ty) -> NonEmpty (Array ty) -> ty
foldr1 f arr = let (initialAcc, rest) = revSplitAt 1 $ getNonEmpty arr
in foldr f (unsafeIndex initialAcc 0) rest
all :: (ty -> Bool) -> Array ty -> Bool
all p ba = loop 0
where
len = length ba
loop !i
| i .==# len = True
| not $ p (unsafeIndex ba i) = False
| otherwise = loop (i + 1)
any :: (ty -> Bool) -> Array ty -> Bool
any p ba = loop 0
where
len = length ba
loop !i
| i .==# len = False
| p (unsafeIndex ba i) = True
| otherwise = loop (i + 1)
isPrefixOf :: Eq ty => Array ty -> Array ty -> Bool
isPrefixOf pre arr
| pLen > pArr = False
| otherwise = pre == take pLen arr
where
!pLen = length pre
!pArr = length arr
isSuffixOf :: Eq ty => Array ty -> Array ty -> Bool
isSuffixOf suffix arr
| pLen > pArr = False
| otherwise = suffix == revTake pLen arr
where
!pLen = length suffix
!pArr = length arr
builderAppend :: PrimMonad state => ty -> Builder (Array ty) (MArray ty) ty state err ()
builderAppend v = Builder $ State $ \(i, st, e) ->
if i .==# chunkSize st
then do
cur <- unsafeFreeze (curChunk st)
newChunk <- new (chunkSize st)
unsafeWrite newChunk 0 v
pure ((), (Offset 1, st { prevChunks = cur : prevChunks st
, prevChunksSize = chunkSize st + prevChunksSize st
, curChunk = newChunk
}, e))
else do
unsafeWrite (curChunk st) i v
pure ((), (i+1, st, e))
builderBuild :: PrimMonad m => Int -> Builder (Array ty) (MArray ty) ty m err () -> m (Either err (Array ty))
builderBuild sizeChunksI ab
| sizeChunksI <= 0 = builderBuild 64 ab
| otherwise = do
first <- new sizeChunks
(i, st, e) <- snd <$> runState (runBuilder ab) (Offset 0, BuildingState [] (CountOf 0) first sizeChunks, Nothing)
case e of
Just err -> pure (Left err)
Nothing -> do
cur <- unsafeFreezeShrink (curChunk st) (offsetAsSize i)
-- Build final array
let totalSize = prevChunksSize st + offsetAsSize i
bytes <- new totalSize >>= fillFromEnd totalSize (cur : prevChunks st) >>= unsafeFreeze
pure (Right bytes)
where
sizeChunks = CountOf sizeChunksI
fillFromEnd _ [] mua = pure mua
fillFromEnd !end (x:xs) mua = do
let sz = length x
let start = end `sizeSub` sz
unsafeCopyAtRO mua (sizeAsOffset start) x (Offset 0) sz
fillFromEnd start xs mua
builderBuild_ :: PrimMonad m => Int -> Builder (Array ty) (MArray ty) ty m () () -> m (Array ty)
builderBuild_ sizeChunksI ab = either (\() -> internalError "impossible output") id <$> builderBuild sizeChunksI ab