summary refs log tree commit diff stats
path: root/lib/pure/collections
diff options
context:
space:
mode:
Diffstat (limited to 'lib/pure/collections')
-rw-r--r--lib/pure/collections/deques.nim121
-rw-r--r--lib/pure/collections/hashcommon.nim5
-rw-r--r--lib/pure/collections/heapqueue.nim15
-rw-r--r--lib/pure/collections/lists.nim26
-rw-r--r--lib/pure/collections/tables.nim5
5 files changed, 118 insertions, 54 deletions
diff --git a/lib/pure/collections/deques.nim b/lib/pure/collections/deques.nim
index b07138e84..d2b0099f2 100644
--- a/lib/pure/collections/deques.nim
+++ b/lib/pure/collections/deques.nim
@@ -50,7 +50,7 @@ runnableExamples:
 
 import std/private/since
 
-import std/math
+import std/[assertions, hashes, math]
 
 type
   Deque*[T] = object
@@ -59,20 +59,29 @@ type
     ## To initialize an empty deque,
     ## use the `initDeque proc <#initDeque,int>`_.
     data: seq[T]
-    head, tail, count, mask: int
+
+    # `head` and `tail` are masked only when accessing an element of `data`
+    # so that `tail - head == data.len` when the deque is full.
+    # They are uint so that incrementing/decrementing them doesn't cause
+    # over/underflow. You can get a number of items with `tail - head`
+    # even if `tail` or `head` is wraps around and `tail < head`, because
+    # `tail - head == (uint.high + 1 + tail) - head` when `tail < head`.
+    head, tail: uint
 
 const
   defaultInitialSize* = 4
 
 template initImpl(result: typed, initialSize: int) =
   let correctSize = nextPowerOfTwo(initialSize)
-  result.mask = correctSize - 1
   newSeq(result.data, correctSize)
 
 template checkIfInitialized(deq: typed) =
-  if deq.mask == 0:
+  if deq.data.len == 0:
     initImpl(deq, defaultInitialSize)
 
+func mask[T](deq: Deque[T]): uint {.inline.} =
+  uint(deq.data.len) - 1
+
 proc initDeque*[T](initialSize: int = defaultInitialSize): Deque[T] =
   ## Creates a new empty deque.
   ##
@@ -85,22 +94,22 @@ proc initDeque*[T](initialSize: int = defaultInitialSize): Deque[T] =
   ## * `toDeque proc <#toDeque,openArray[T]>`_
   result.initImpl(initialSize)
 
-proc len*[T](deq: Deque[T]): int {.inline.} =
+func len*[T](deq: Deque[T]): int {.inline.} =
   ## Returns the number of elements of `deq`.
-  result = deq.count
+  int(deq.tail - deq.head)
 
 template emptyCheck(deq) =
   # Bounds check for the regular deque access.
   when compileOption("boundChecks"):
-    if unlikely(deq.count < 1):
+    if unlikely(deq.len < 1):
       raise newException(IndexDefect, "Empty deque.")
 
 template xBoundsCheck(deq, i) =
   # Bounds check for the array like accesses.
   when compileOption("boundChecks"): # `-d:danger` or `--checks:off` should disable this.
-    if unlikely(i >= deq.count): # x < deq.low is taken care by the Natural parameter
+    if unlikely(i >= deq.len): # x < deq.low is taken care by the Natural parameter
       raise newException(IndexDefect,
-                         "Out of bounds: " & $i & " > " & $(deq.count - 1))
+                         "Out of bounds: " & $i & " > " & $(deq.len - 1))
     if unlikely(i < 0): # when used with BackwardsIndex
       raise newException(IndexDefect,
                          "Out of bounds: " & $i & " < 0")
@@ -114,7 +123,7 @@ proc `[]`*[T](deq: Deque[T], i: Natural): lent T {.inline.} =
     doAssertRaises(IndexDefect, echo a[8])
 
   xBoundsCheck(deq, i)
-  return deq.data[(deq.head + i) and deq.mask]
+  return deq.data[(deq.head + i.uint) and deq.mask]
 
 proc `[]`*[T](deq: var Deque[T], i: Natural): var T {.inline.} =
   ## Accesses the `i`-th element of `deq` and returns a mutable
@@ -125,7 +134,7 @@ proc `[]`*[T](deq: var Deque[T], i: Natural): var T {.inline.} =
     assert a[0] == 11
 
   xBoundsCheck(deq, i)
-  return deq.data[(deq.head + i) and deq.mask]
+  return deq.data[(deq.head + i.uint) and deq.mask]
 
 proc `[]=`*[T](deq: var Deque[T], i: Natural, val: sink T) {.inline.} =
   ## Sets the `i`-th element of `deq` to `val`.
@@ -137,7 +146,7 @@ proc `[]=`*[T](deq: var Deque[T], i: Natural, val: sink T) {.inline.} =
 
   checkIfInitialized(deq)
   xBoundsCheck(deq, i)
-  deq.data[(deq.head + i) and deq.mask] = val
+  deq.data[(deq.head + i.uint) and deq.mask] = val
 
 proc `[]`*[T](deq: Deque[T], i: BackwardsIndex): lent T {.inline.} =
   ## Accesses the backwards indexed `i`-th element.
@@ -190,10 +199,8 @@ iterator items*[T](deq: Deque[T]): lent T =
     let a = [10, 20, 30, 40, 50].toDeque
     assert toSeq(a.items) == @[10, 20, 30, 40, 50]
 
-  var i = deq.head
-  for c in 0 ..< deq.count:
-    yield deq.data[i]
-    i = (i + 1) and deq.mask
+  for c in 0 ..< deq.len:
+    yield deq.data[(deq.head + c.uint) and deq.mask]
 
 iterator mitems*[T](deq: var Deque[T]): var T =
   ## Yields every element of `deq`, which can be modified.
@@ -207,10 +214,8 @@ iterator mitems*[T](deq: var Deque[T]): var T =
       x = 5 * x - 1
     assert $a == "[49, 99, 149, 199, 249]"
 
-  var i = deq.head
-  for c in 0 ..< deq.count:
-    yield deq.data[i]
-    i = (i + 1) and deq.mask
+  for c in 0 ..< deq.len:
+    yield deq.data[(deq.head + c.uint) and deq.mask]
 
 iterator pairs*[T](deq: Deque[T]): tuple[key: int, val: T] =
   ## Yields every `(position, value)`-pair of `deq`.
@@ -220,10 +225,8 @@ iterator pairs*[T](deq: Deque[T]): tuple[key: int, val: T] =
     let a = [10, 20, 30].toDeque
     assert toSeq(a.pairs) == @[(0, 10), (1, 20), (2, 30)]
 
-  var i = deq.head
-  for c in 0 ..< deq.count:
-    yield (c, deq.data[i])
-    i = (i + 1) and deq.mask
+  for c in 0 ..< deq.len:
+    yield (c, deq.data[(deq.head + c.uint) and deq.mask])
 
 proc contains*[T](deq: Deque[T], item: T): bool {.inline.} =
   ## Returns true if `item` is in `deq` or false if not found.
@@ -242,8 +245,9 @@ proc contains*[T](deq: Deque[T], item: T): bool {.inline.} =
 
 proc expandIfNeeded[T](deq: var Deque[T]) =
   checkIfInitialized(deq)
-  var cap = deq.mask + 1
-  if unlikely(deq.count >= cap):
+  let cap = deq.data.len
+  assert deq.len <= cap
+  if unlikely(deq.len == cap):
     var n = newSeq[T](cap * 2)
     var i = 0
     for x in mitems(deq):
@@ -251,8 +255,7 @@ proc expandIfNeeded[T](deq: var Deque[T]) =
       else: n[i] = move(x)
       inc i
     deq.data = move(n)
-    deq.mask = cap * 2 - 1
-    deq.tail = deq.count
+    deq.tail = cap.uint
     deq.head = 0
 
 proc addFirst*[T](deq: var Deque[T], item: sink T) =
@@ -267,9 +270,8 @@ proc addFirst*[T](deq: var Deque[T], item: sink T) =
     assert $a == "[50, 40, 30, 20, 10]"
 
   expandIfNeeded(deq)
-  inc deq.count
-  deq.head = (deq.head - 1) and deq.mask
-  deq.data[deq.head] = item
+  dec deq.head
+  deq.data[deq.head and deq.mask] = item
 
 proc addLast*[T](deq: var Deque[T], item: sink T) =
   ## Adds an `item` to the end of `deq`.
@@ -283,9 +285,8 @@ proc addLast*[T](deq: var Deque[T], item: sink T) =
     assert $a == "[10, 20, 30, 40, 50]"
 
   expandIfNeeded(deq)
-  inc deq.count
-  deq.data[deq.tail] = item
-  deq.tail = (deq.tail + 1) and deq.mask
+  deq.data[deq.tail and deq.mask] = item
+  inc deq.tail
 
 proc toDeque*[T](x: openArray[T]): Deque[T] {.since: (1, 3).} =
   ## Creates a new deque that contains the elements of `x` (in the same order).
@@ -314,7 +315,7 @@ proc peekFirst*[T](deq: Deque[T]): lent T {.inline.} =
     assert len(a) == 5
 
   emptyCheck(deq)
-  result = deq.data[deq.head]
+  result = deq.data[deq.head and deq.mask]
 
 proc peekLast*[T](deq: Deque[T]): lent T {.inline.} =
   ## Returns the last element of `deq`, but does not remove it from the deque.
@@ -344,7 +345,7 @@ proc peekFirst*[T](deq: var Deque[T]): var T {.inline, since: (1, 3).} =
     assert $a == "[99, 20, 30, 40, 50]"
 
   emptyCheck(deq)
-  result = deq.data[deq.head]
+  result = deq.data[deq.head and deq.mask]
 
 proc peekLast*[T](deq: var Deque[T]): var T {.inline, since: (1, 3).} =
   ## Returns a mutable reference to the last element of `deq`,
@@ -377,9 +378,8 @@ proc popFirst*[T](deq: var Deque[T]): T {.inline, discardable.} =
     assert $a == "[20, 30, 40, 50]"
 
   emptyCheck(deq)
-  dec deq.count
-  result = move deq.data[deq.head]
-  deq.head = (deq.head + 1) and deq.mask
+  result = move deq.data[deq.head and deq.mask]
+  inc deq.head
 
 proc popLast*[T](deq: var Deque[T]): T {.inline, discardable.} =
   ## Removes and returns the last element of the `deq`.
@@ -394,9 +394,8 @@ proc popLast*[T](deq: var Deque[T]): T {.inline, discardable.} =
     assert $a == "[10, 20, 30, 40]"
 
   emptyCheck(deq)
-  dec deq.count
-  deq.tail = (deq.tail - 1) and deq.mask
-  result = move deq.data[deq.tail]
+  dec deq.tail
+  result = move deq.data[deq.tail and deq.mask]
 
 proc clear*[T](deq: var Deque[T]) {.inline.} =
   ## Resets the deque so that it is empty.
@@ -410,7 +409,6 @@ proc clear*[T](deq: var Deque[T]) {.inline.} =
     assert len(a) == 0
 
   for el in mitems(deq): destroy(el)
-  deq.count = 0
   deq.tail = deq.head
 
 proc shrink*[T](deq: var Deque[T], fromFirst = 0, fromLast = 0) =
@@ -430,19 +428,17 @@ proc shrink*[T](deq: var Deque[T], fromFirst = 0, fromLast = 0) =
     a.shrink(fromFirst = 2, fromLast = 1)
     assert $a == "[30, 40]"
 
-  if fromFirst + fromLast > deq.count:
+  if fromFirst + fromLast > deq.len:
     clear(deq)
     return
 
   for i in 0 ..< fromFirst:
-    destroy(deq.data[deq.head])
-    deq.head = (deq.head + 1) and deq.mask
+    destroy(deq.data[deq.head and deq.mask])
+    inc deq.head
 
   for i in 0 ..< fromLast:
     destroy(deq.data[(deq.tail - 1) and deq.mask])
-    deq.tail = (deq.tail - 1) and deq.mask
-
-  dec deq.count, fromFirst + fromLast
+    dec deq.tail
 
 proc `$`*[T](deq: Deque[T]): string =
   ## Turns a deque into its string representation.
@@ -455,3 +451,30 @@ proc `$`*[T](deq: Deque[T]): string =
     if result.len > 1: result.add(", ")
     result.addQuoted(x)
   result.add("]")
+
+func `==`*[T](deq1, deq2: Deque[T]): bool =
+  ## The `==` operator for Deque.
+  ## Returns `true` if both deques contains the same values in the same order.
+  runnableExamples:
+    var a, b = initDeque[int]()
+    a.addFirst(2)
+    a.addFirst(1)
+    b.addLast(1)
+    b.addLast(2)
+    doAssert a == b
+
+  if deq1.len != deq2.len:
+    return false
+
+  for i in 0 ..< deq1.len:
+    if deq1.data[(deq1.head + i.uint) and deq1.mask] != deq2.data[(deq2.head + i.uint) and deq2.mask]:
+      return false
+
+  true
+
+func hash*[T](deq: Deque[T]): Hash =
+  ## Hashing of Deque.
+  var h: Hash = 0
+  for x in deq:
+    h = h !& hash(x)
+  !$h
diff --git a/lib/pure/collections/hashcommon.nim b/lib/pure/collections/hashcommon.nim
index 8fd4c6e08..17785c8c7 100644
--- a/lib/pure/collections/hashcommon.nim
+++ b/lib/pure/collections/hashcommon.nim
@@ -58,7 +58,10 @@ proc rawGetKnownHC[X, A](t: X, key: A, hc: Hash): int {.inline.} =
 template genHashImpl(key, hc: typed) =
   hc = hash(key)
   if hc == 0: # This almost never taken branch should be very predictable.
-    hc = 314159265 # Value doesn't matter; Any non-zero favorite is fine.
+    when sizeof(int) < 4:
+      hc = 31415 # Value doesn't matter; Any non-zero favorite is fine <= 16-bit.
+    else:
+      hc = 314159265 # Value doesn't matter; Any non-zero favorite is fine.
 
 template genHash(key: typed): Hash =
   var res: Hash
diff --git a/lib/pure/collections/heapqueue.nim b/lib/pure/collections/heapqueue.nim
index bcfdf37c2..96f9b4430 100644
--- a/lib/pure/collections/heapqueue.nim
+++ b/lib/pure/collections/heapqueue.nim
@@ -47,6 +47,9 @@ runnableExamples:
 
 import std/private/since
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 type HeapQueue*[T] = object
   ## A heap queue, commonly known as a priority queue.
   data: seq[T]
@@ -73,6 +76,13 @@ proc `[]`*[T](heap: HeapQueue[T], i: Natural): lent T {.inline.} =
   ## Accesses the i-th element of `heap`.
   heap.data[i]
 
+iterator items*[T](heap: HeapQueue[T]): lent T {.inline, since: (2, 1, 1).} =
+  ## Iterates over each item of `heap`.
+  let L = len(heap)
+  for i in 0 .. high(heap.data):
+    yield heap.data[i]
+    assert(len(heap) == L, "the length of the HeapQueue changed while iterating over it")
+
 proc heapCmp[T](x, y: T): bool {.inline.} = x < y
 
 proc siftup[T](heap: var HeapQueue[T], startpos, p: int) =
@@ -178,6 +188,11 @@ proc find*[T](heap: HeapQueue[T], x: T): int {.since: (1, 3).} =
   for i in 0 ..< heap.len:
     if heap[i] == x: return i
 
+proc contains*[T](heap: HeapQueue[T], x: T): bool {.since: (2, 1, 1).} =
+  ## Returns true if `x` is in `heap` or false if not found. This is a shortcut
+  ## for `find(heap, x) >= 0`.
+  result = find(heap, x) >= 0
+
 proc del*[T](heap: var HeapQueue[T], index: Natural) =
   ## Removes the element at `index` from `heap`, maintaining the heap invariant.
   runnableExamples:
diff --git a/lib/pure/collections/lists.nim b/lib/pure/collections/lists.nim
index b9d5c48eb..6b88747ef 100644
--- a/lib/pure/collections/lists.nim
+++ b/lib/pure/collections/lists.nim
@@ -384,9 +384,7 @@ proc prependMoved*[T: SomeLinkedList](a, b: var T) {.since: (1, 5, 1).} =
     assert s == [0, 1, 0, 1, 0, 1]
 
   b.addMoved(a)
-  when defined(js): # XXX: swap broken in js; bug #16771
-    (b, a) = (a, b)
-  else: swap a, b
+  swap a, b
 
 proc add*[T](L: var SinglyLinkedList[T], n: SinglyLinkedNode[T]) {.inline.} =
   ## Appends (adds to the end) a node `n` to `L`. Efficiency: O(1).
@@ -983,6 +981,17 @@ func toSinglyLinkedList*[T](elems: openArray[T]): SinglyLinkedList[T] {.since: (
   for elem in elems.items:
     result.add(elem)
 
+func toSinglyLinkedRing*[T](elems: openArray[T]): SinglyLinkedRing[T] =
+  ## Creates a new `SinglyLinkedRing` from the members of `elems`.
+  runnableExamples:
+    from std/sequtils import toSeq
+    let a = [1, 2, 3, 4, 5].toSinglyLinkedRing
+    assert a.toSeq == [1, 2, 3, 4, 5]
+
+  result = initSinglyLinkedRing[T]()
+  for elem in elems.items:
+    result.add(elem)
+
 func toDoublyLinkedList*[T](elems: openArray[T]): DoublyLinkedList[T] {.since: (1, 5, 1).} =
   ## Creates a new `DoublyLinkedList` from the members of `elems`.
   runnableExamples:
@@ -993,3 +1002,14 @@ func toDoublyLinkedList*[T](elems: openArray[T]): DoublyLinkedList[T] {.since: (
   result = initDoublyLinkedList[T]()
   for elem in elems.items:
     result.add(elem)
+
+func toDoublyLinkedRing*[T](elems: openArray[T]): DoublyLinkedRing[T] =
+  ## Creates a new `DoublyLinkedRing` from the members of `elems`.
+  runnableExamples:
+    from std/sequtils import toSeq
+    let a = [1, 2, 3, 4, 5].toDoublyLinkedRing
+    assert a.toSeq == [1, 2, 3, 4, 5]
+
+  result = initDoublyLinkedRing[T]()
+  for elem in elems.items:
+    result.add(elem)
diff --git a/lib/pure/collections/tables.nim b/lib/pure/collections/tables.nim
index 8e4a3c35f..d414caeed 100644
--- a/lib/pure/collections/tables.nim
+++ b/lib/pure/collections/tables.nim
@@ -278,6 +278,7 @@ proc initTable*[A, B](initialSize = defaultInitialSize): Table[A, B] =
     let
       a = initTable[int, string]()
       b = initTable[char, seq[int]]()
+  result = default(Table[A, B])
   initImpl(result, initialSize)
 
 proc `[]=`*[A, B](t: var Table[A, B], key: A, val: sink B) =
@@ -1346,6 +1347,7 @@ proc initOrderedTable*[A, B](initialSize = defaultInitialSize): OrderedTable[A,
     let
       a = initOrderedTable[int, string]()
       b = initOrderedTable[char, seq[int]]()
+  result = default(OrderedTable[A, B])
   initImpl(result, initialSize)
 
 proc `[]=`*[A, B](t: var OrderedTable[A, B], key: A, val: sink B) =
@@ -1437,7 +1439,7 @@ proc hasKey*[A, B](t: OrderedTable[A, B], key: A): bool =
     doAssert a.hasKey('a') == true
     doAssert a.hasKey('z') == false
 
-  var hc: Hash
+  var hc: Hash = default(Hash)
   result = rawGet(t, key, hc) >= 0
 
 proc contains*[A, B](t: OrderedTable[A, B], key: A): bool =
@@ -2336,6 +2338,7 @@ proc initCountTable*[A](initialSize = defaultInitialSize): CountTable[A] =
   ## * `toCountTable proc<#toCountTable,openArray[A]>`_
   ## * `newCountTable proc<#newCountTable>`_ for creating a
   ##   `CountTableRef`
+  result = default(CountTable[A])
   initImpl(result, initialSize)
 
 proc toCountTable*[A](keys: openArray[A]): CountTable[A] =