Add ArrayDequeue #490
Add ArrayDequeue #490
Conversation
|
|
||
| def toQueue = new Queue(first0, last0, len) | ||
| @deprecated("Use to(Queue) instead", "2.13.0") | ||
| def toQueue: Queue[A] = to(Queue) |
There was a problem hiding this comment.
Queue used to be built on top of MutableList, but that’s not the case anymore with this PR. Consequently I’ve deprecated this method.
| with LinearSeqOps[A, Queue, Queue[A]] | ||
| class Queue[A] protected(array: Array[AnyRef], start: Int, end: Int) | ||
| extends ArrayDeque[A](array, start, end) | ||
| with IndexedSeqOps[A, Queue, Queue[A]] |
There was a problem hiding this comment.
Queue switches from being a LinearSeq to an IndexedSeq. This might break existing usage.
| this | ||
| } | ||
|
|
||
| override def slice(from: Int, until: Int): IterableCC[A] = { |
There was a problem hiding this comment.
This is a bit hacky: I’ve changed the return type to be IterableCC[A] so that when this operation is inherited by Queue its return type is refined accordingly.
There was a problem hiding this comment.
If Queue isn't supposed to override it, shouldn't ofArray return IterableCC, too?
There was a problem hiding this comment.
ofArray is supposed to be overridden.
julienrf
force-pushed
the
array-dequeue-squashed
branch
from
beb293a to
b15d7d4
Compare
|
@pathikrit I’d be happy to get your feedback on my changes. |
julienrf
force-pushed
the
array-dequeue-squashed
branch
from
4091af0 to
eed5130
Compare
julienrf
force-pushed
the
array-dequeue-squashed
branch
from
eed5130 to
2afd05c
Compare
julienrf
force-pushed
the
array-dequeue-squashed
branch
from
09e0508 to
124184d
Compare
|
I’ve tried running the benchmarks but for some reason that I ignore appending and prepending elements ot an |
| this | ||
| } | ||
|
|
||
| override def slice(from: Int, until: Int): IterableCC[A] = { |
There was a problem hiding this comment.
If Queue isn't supposed to override it, shouldn't ofArray return IterableCC, too?
| * @param destStart | ||
| * @param maxItems | ||
| */ | ||
| def copySliceToArray(srcStart: Int, dest: Array[_], destStart: Int, maxItems: Int): dest.type = { |
There was a problem hiding this comment.
Does this need to be public?
| requireBounds(srcStart) | ||
| val startIdx = start_+(srcStart) | ||
| val block1 = Math.min(toCopy, array.length - startIdx) | ||
| Array.copy(src = array, srcPos = startIdx, dest = dest, destPos = destStart, length = block1) |
There was a problem hiding this comment.
copySliceToArray is usually called with new array as dest and destStart = 0. This case could be optimized to avoid initializing the start of the array (where the copy of block1 goes).
There was a problem hiding this comment.
Where do we initialize the start of the array?
There was a problem hiding this comment.
When you create a new array and pass that to the method.
There was a problem hiding this comment.
Sorry but I don’t see what we could do instead.
There was a problem hiding this comment.
Create a different version of copySliceToArray (at least for internal use) that allocates the target array on its own using java.util.Arrays.copyOf. Anyway, this is a minor performance optimization (which we already did in ArrayOps) that can be done later. It shouldn't hold up this PR.
| decrementLength() | ||
| res | ||
| } | ||
| def enqueue(elem1: A, elem2: A, elems: A*): this.type = enqueue(elem1).enqueue(elem2).enqueueAll(elems.toStrawman) |
There was a problem hiding this comment.
This could force a resize to the correct target size before adding any elements if elems.knownSize >= 0
szeiger
left a comment
szeiger
left a comment
There was a problem hiding this comment.
The out of memory problem is worrying but since it also happens for ArrayBuffer it should be unrelated to the new implementation here. The other problems I commented on are minor and could be fixed later.
3 participants
I picked the content of #49, fixed the remaining compilation errors, and rebased on master.
In summary, the PR introduces the
ArrayDequecollection and implementsQueueon top of it.MutableListandLinkedListare removed.