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Merge pull request #434 from haskell/access-to-vector-internal
Add `unsafeToArray` function for getting the underlying boxed `Array`
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‎.github/workflows/ci.yml

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@@ -18,28 +18,28 @@ jobs:
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matrix:
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include:
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# Linux
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- { cabal: "3.4", os: ubuntu-latest, ghc: "8.0.2" }
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- { cabal: "3.4", os: ubuntu-latest, ghc: "8.2.2" }
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- { cabal: "3.4", os: ubuntu-latest, ghc: "8.4.4" }
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- { cabal: "3.4", os: ubuntu-latest, ghc: "8.6.5" }
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- { cabal: "3.4", os: ubuntu-latest, ghc: "8.8.4" }
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- { cabal: "3.4", os: ubuntu-latest, ghc: "8.10.7" }
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- { cabal: "3.4", os: ubuntu-latest, ghc: "9.0.1" }
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- { cabal: "3.4", os: ubuntu-latest, ghc: "9.2.1" }
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- { cabal: "3.6", os: ubuntu-latest, ghc: "8.0.2" }
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- { cabal: "3.6", os: ubuntu-latest, ghc: "8.2.2" }
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- { cabal: "3.6", os: ubuntu-latest, ghc: "8.4.4" }
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- { cabal: "3.6", os: ubuntu-latest, ghc: "8.6.5" }
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- { cabal: "3.6", os: ubuntu-latest, ghc: "8.8.4" }
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- { cabal: "3.6", os: ubuntu-latest, ghc: "8.10.7" }
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- { cabal: "3.6", os: ubuntu-latest, ghc: "9.0.1" }
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- { cabal: "3.6", os: ubuntu-latest, ghc: "9.2.1" }
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# Win
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- { cabal: "3.2", os: windows-latest, ghc: "8.4.4" }
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- { cabal: "3.2", os: windows-latest, ghc: "8.6.5" }
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- { cabal: "3.6", os: windows-latest, ghc: "8.4.4" }
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# OOM when building tests
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# - { cabal: "3.4", os: windows-latest, ghc: "8.8.4" }
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# - { cabal: "3.4", os: windows-latest, ghc: "8.10.4" }
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# - { cabal: "3.6", os: windows-latest, ghc: "8.6.5" }
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# - { cabal: "3.6", os: windows-latest, ghc: "8.8.4" }
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# - { cabal: "3.6", os: windows-latest, ghc: "8.10.4" }
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# Too flaky:
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# - { cabal: "3.4", os: windows-latest, ghc: "9.0.1" }
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# - { cabal: "3.6", os: windows-latest, ghc: "9.0.1" }
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# MacOS
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- { cabal: "3.2", os: macOS-latest, ghc: "8.4.4" }
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- { cabal: "3.2", os: macOS-latest, ghc: "8.6.5" }
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- { cabal: "3.2", os: macOS-latest, ghc: "8.8.4" }
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- { cabal: "3.2", os: macOS-latest, ghc: "8.10.7" }
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- { cabal: "3.4", os: macOS-latest, ghc: "9.0.1" }
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- { cabal: "3.6", os: macOS-latest, ghc: "8.4.4" }
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- { cabal: "3.6", os: macOS-latest, ghc: "8.6.5" }
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- { cabal: "3.6", os: macOS-latest, ghc: "8.8.4" }
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- { cabal: "3.6", os: macOS-latest, ghc: "8.10.7" }
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- { cabal: "3.6", os: macOS-latest, ghc: "9.0.1" }
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fail-fast: false
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steps:

‎vector/changelog.md

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@@ -47,6 +47,8 @@
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* Add `groupBy` and `group` for `Data.Vector.Generic` and the specialized
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version in `Data.Vector`, `Data.Vector.Unboxed`, `Data.Vector.Storable` and
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`Data.Vector.Primitive`.
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* Add `toArraySlice` and `unsafeFromArraySlice` functions for conversion to and
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from the underlying boxed `Array`.
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# Changes in version 0.12.3.1
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‎vector/src/Data/Vector.hs

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@@ -163,7 +163,7 @@ module Data.Vector (
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toList, Data.Vector.fromList, Data.Vector.fromListN,
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-- ** Arrays
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fromArray, toArray,
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toArray, fromArray, toArraySlice, unsafeFromArraySlice,
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-- ** Other vector types
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G.convert,
@@ -2136,16 +2136,43 @@ fromListN = G.fromListN
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-- @since 0.12.2.0
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fromArray :: Array a -> Vector a
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{-# INLINE fromArray #-}
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fromArray x = Vector 0 (sizeofArray x) x
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fromArray arr = Vector 0 (sizeofArray arr) arr
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-- | /O(n)/ Convert a vector to an array.
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--
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-- @since 0.12.2.0
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toArray :: Vector a -> Array a
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{-# INLINE toArray #-}
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toArray (Vector offset size arr)
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| offset == 0 && size == sizeofArray arr = arr
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| otherwise = cloneArray arr offset size
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toArray (Vector offset len arr)
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| offset == 0 && len == sizeofArray arr = arr
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| otherwise = cloneArray arr offset len
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-- | /O(1)/ Extract the underlying `Array`, offset where vector starts and the
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-- total number of elements in the vector. Below property always holds:
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--
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-- > let (array, offset, len) = toArraySlice v
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-- > v === unsafeFromArraySlice len offset array
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--
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-- @since 0.13.0.0
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toArraySlice :: Vector a -> (Array a, Int, Int)
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{-# INLINE toArraySlice #-}
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toArraySlice (Vector offset len arr) = (arr, offset, len)
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-- | /O(1)/ Convert an array slice to a vector. This function is very unsafe,
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-- because constructing an invalid vector can yield almost all other safe
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-- functions in this module unsafe. These are equivalent:
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--
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-- > unsafeFromArraySlice len offset === unsafeTake len . unsafeDrop offset . fromArray
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--
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-- @since 0.13.0.0
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unsafeFromArraySlice ::
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Array a -- ^ Immutable boxed array.
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-> Int -- ^ Offset
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-> Int -- ^ Length
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-> Vector a
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{-# INLINE unsafeFromArraySlice #-}
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unsafeFromArraySlice arr offset len = Vector offset len arr
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-- Conversions - Mutable vectors
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-- -----------------------------

‎vector/tests/Tests/Vector/UnitTests.hs

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@@ -91,6 +91,8 @@ tests =
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, testGroup "Data.Vector"
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[ testCase "MonadFix" checkMonadFix
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, testCase "toFromArray" toFromArray
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, testCase "toFromArraySlice" toFromArraySlice
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, testCase "toFromArraySliceUnsafe" toFromArraySliceUnsafe
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, testCase "toFromMutableArray" toFromMutableArray
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]
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]
@@ -202,6 +204,22 @@ toFromArray =
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mkArrayRoundtrip $ \name v ->
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assertEqual name v $ Boxed.fromArray (Boxed.toArray v)
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toFromArraySlice :: Assertion
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toFromArraySlice =
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mkArrayRoundtrip $ \name v ->
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case Boxed.toArraySlice v of
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(arr, off, n) ->
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assertEqual name v $
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Boxed.take n (Boxed.drop off (Boxed.fromArray arr))
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toFromArraySliceUnsafe :: Assertion
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toFromArraySliceUnsafe =
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mkArrayRoundtrip $ \name v ->
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case Boxed.toArraySlice v of
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(arr, off, n) ->
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assertEqual name v $
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Boxed.unsafeFromArraySlice arr off n
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toFromMutableArray :: Assertion
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toFromMutableArray = mkArrayRoundtrip assetRoundtrip
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where

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