Add internal block type for use in the compiler. IncrementalBuilder only maintains two states
#11750
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TIHan
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block type for use in the compiler. IncrementalBuilder only maintains two states. block type for use in the compiler. IncrementalBuilder only maintains two states
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I did a review of the block api, I hope that's alright.
Also, sometimes there are reasons to get the underlying array cheaply. I'm using this, posted below, in our codebase here and there. Though going fully unsafe you could do Unsafe.As<Block<'T>, 'T[]> as it's the only field in the struct. I just prefer my code to die a little nicer than with a segfault in the very unlikely case ImmutableArray changes implementations 😅.
let unsafeGetArray(value: ImmutableArray<'T>) =
match MemoryMarshal.TryGetArray(value.AsMemory()) with
| false, _ -> failwith "Expected ImmutableArray to wrap a managed array but it didn't."
| true, seg -> seg.Array
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@NinoFloris of course! Thank you for reviewing :) |
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@NinoFloris This should be a lot better. :) I didn't realize how naïve my original impl was. |
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| let choose (chooser: 'T -> 'U option) (arr: block<'T>) : block<'U> = | ||
| let builder = ImmutableArray.CreateBuilder(arr.Length) | ||
| for i = 0 to arr.Length - 1 do | ||
| let result = chooser arr.[i] | ||
| if result.IsSome then | ||
| builder.Add(result.Value) | ||
| builder.ToImmutable() | ||
| builder.Capacity <- builder.Count |
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If you don't know the length it doesn't matter too much if you do ToImmutable. You'll do a copy by changing capacity anyway.
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Changing the capacity will only copy if the count is different.
| let builder = ImmutableArray.CreateBuilder(acc) | ||
| for i = 0 to arrs.Length - 1 do | ||
| builder.AddRange(arrs.[i]) | ||
| builder.MoveToImmutable() |
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Missing capacity <- count or ToImmutable here, as capacity could be anything.
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I think this is fine. acc is the total length of the final array.
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Ah I completely missed the the length summing loop, yep it's fine!
| ImmutableArray.Create(item) | ||
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| let filter predicate (arr: block<'T>) : block<'T> = | ||
| let builder = ImmutableArray.CreateBuilder(arr.Length) |
This is mostly a refactoring PR. It does add the
blocktype for internal compiler use; it is basicallyImmutableArray<'T>but with F# idiomatic collection functions.Incremental Builder changes:
IncrementalBuilderInitialStateto group the initial state when creating anIncrementalBuilderinternally.IncrementalBuilderto be top-level.IncrementalBuildernow manages only two states:IncrementalBuilderInitialStateandIncrementalBuilderState.