diff options
| -rw-r--r-- | lib/pure/collections/queues.nim | 45 |
1 files changed, 18 insertions, 27 deletions
diff --git a/lib/pure/collections/queues.nim b/lib/pure/collections/queues.nim index 96c6c75d4..5ec1d05bf 100644 --- a/lib/pure/collections/queues.nim +++ b/lib/pure/collections/queues.nim @@ -34,26 +34,9 @@ ## while q.len > 0: # checking if the queue is empty ## echo q.pop() ## -## ## Note: For inter thread communication use ## a `Channel <channels.html>`_ instead. -proc englishOrdinal(n: SomeInteger): string = - # Temporary proc. Needs to be moved somewhere else as it can be reused in - # other places too. - # If this accepted number strings instead and only gave out the letters it - # would be more flexible, permitting things like 1.100.000th, 34,545,321st - # but it would be harder and more error prone to use. - let num = $n - if num.len > 1 and num[^2] == '1': - return num & "th" - else: - case num[^1] - of '1': return num & "st" - of '2': return num & "nd" - of '3': return num & "rd" - else: return num & "th" - import math type @@ -66,8 +49,12 @@ type proc initQueue*[T](initialSize: int = 4): Queue[T] = ## Create a new queue. ## Optionally, the initial capacity can be reserved via `initialSize` as a - ## performance optimization. `initialSize` needs to be a power of 2. - ## The lenght of a newly created queue will still be 0. + ## performance optimization. The length of a newly created queue will still + ## be 0. + ## + ## `initialSize` needs to be a power of two. If you need to accept runtime + ## values for this you could use the ``nextPowerOfTwo`` proc from the + ## `math <math.html>`_ module. assert isPowerOfTwo(initialSize) result.mask = initialSize-1 newSeq(result.data, initialSize) @@ -90,17 +77,13 @@ template emptyCheck(q) = when compileOption("boundChecks"): if unlikely(q.count < 1): raise newException(IndexError, "Empty queue.") - discard template xBoundsCheck(q, i) = # Bounds check for the array like accesses. when compileOption("boundChecks"): # d:release should disable this. if unlikely(i >= q.count): # x < q.low is taken care by the Natural parameter raise newException(IndexError, - "Tried to access the " & englishOrdinal(i+1) & - " element of the queue but it has only " & - $q.count & " elements.") - discard + "Out of bounds: " & $i & " > " & $(q.count - 1)) proc front*[T](q: Queue[T]): T {.inline.}= ## Return the oldest element of `q`. Equivalent to `q.pop()` but does not @@ -167,7 +150,7 @@ proc add*[T](q: var Queue[T], item: T) = ## Add an `item` to the end of the queue `q`. var cap = q.mask+1 if unlikely(q.count >= cap): - var n {.noinit.} = newSeq[T](cap*2) + var n = newSeq[T](cap*2) for i, x in q: shallowCopy(n[i], x) # does not use copyMem because the GC. shallowCopy(q.data, n) @@ -196,13 +179,13 @@ proc dequeue*[T](q: var Queue[T]): T = proc `$`*[T](q: Queue[T]): string = ## Turn a queue into its string representation. result = "[" - for x in q: + for x in items(q): # Don't remove the items here for reasons that don't fit in this margin. if result.len > 1: result.add(", ") result.add($x) result.add("]") when isMainModule: - var q = initQueue[int]() + var q = initQueue[int](1) q.add(123) q.add(9) q.enqueue(4) @@ -247,6 +230,14 @@ when isMainModule: except IndexError: discard + # grabs some types of resize error. + q = initQueue[int]() + for i in 1 .. 4: q.add i + q.pop() + q.pop() + for i in 5 .. 8: q.add i + assert $q == "[3, 4, 5, 6, 7, 8]" + # Similar to proc from the documentation example proc foo(a, b: Positive) = # assume random positive values for `a` and `b`. var q = initQueue[int]() |