Add AsyncSeq.chunkBySize

[brianberns]

Just like Seq.chunkBySize. Possible implementation:

    let chunkBySize (chunkSize : int) (source: AsyncSeq<'a>) =
        asyncSeq {
            use enumerator = source.GetEnumerator()
            let mutable isFinished = false
            while not isFinished do
                let chunk = ResizeArray<'a>(chunkSize)
                while chunk.Count < chunkSize && not isFinished do
                    match! enumerator.MoveNext() with
                        | Some item -> chunk.Add(item)
                        | None -> isFinished <- true
                if chunk.Count > 0 then
                    yield chunk.ToArray()
        }

[njlr]

Provided by bufferByCount

FSharp.Control.AsyncSeq/src/FSharp.Control.AsyncSeq/AsyncSeq.fs

Lines 1547 to 1562 in 4bdcf15

	let bufferByCount (bufferSize:int) (source:AsyncSeq<'T>) : AsyncSeq<'T[]> =
	if (bufferSize < 1) then invalidArg "bufferSize" "must be positive"
	asyncSeq {
	let buffer = new ResizeArray<_>()
	use ie = source.GetEnumerator()
	let! move = ie.MoveNext()
	let b = ref move
	while b.Value.IsSome do
	buffer.Add b.Value.Value
	if buffer.Count = bufferSize then
	yield buffer.ToArray()
	buffer.Clear()
	let! moven = ie.MoveNext()
	b := moven
	if (buffer.Count > 0) then
	yield buffer.ToArray() }

Suggest closing this.

[brianberns]

Ah, that's good to know. Thank you. I would still suggest adding chunkBySize as a synonym, however, since that is now the standard F# name for a function with this behavior.

[njlr]

Related fsprojects/FSharp.Control.TaskSeq#265

@dsyme @abelbraaksma I think these should be aligned. Any preference?