//
// System.Collections.Generic.Stack
//
// Authors:
// Martin Baulig (martin@ximian.com)
// Ben Maurer (bmaurer@ximian.com)
//
// (C) 2003, 2004 Novell, Inc.
//
//
// Copyright (C) 2004 Novell, Inc (http://www.novell.com)
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
using System;
using System.Runtime.InteropServices;
using System.Diagnostics;
namespace System.Collections.Generic{
[ComVisible (false)]
[Serializable]
[DebuggerDisplay ("Count={Count}")]
[DebuggerTypeProxy (typeof (CollectionDebuggerView))]
public class Stack <T> : IEnumerable <T>, ICollection, IEnumerable
{
T [] _array;
int _size;
int _version;
private const int INITIAL_SIZE = 16;
public Stack ()
{
}
public Stack (int count)
{
if (count < 0)
throw new ArgumentOutOfRangeException ("count");
_array = new T [count];
}
public Stack (IEnumerable <T> collection)
{
if (collection == null)
throw new ArgumentNullException ("collection");
ICollection <T> col = collection as ICollection <T>;
if (col != null) {
_size = col.Count;
_array = new T [_size];
col.CopyTo (_array, 0);
} else {
foreach (T t in collection)
Push (t);
}
}
public void Clear ()
{
if (_array != null)
Array.Clear (_array, 0, _array.Length);
_size = 0;
_version ++;
}
public bool Contains (T t)
{
return _array != null && Array.IndexOf (_array, t, 0, _size) != -1;
}
public void CopyTo (T [] dest, int idx)
{
if (dest == null)
throw new ArgumentNullException ("dest");
if (idx < 0)
throw new ArgumentOutOfRangeException ("idx");
// this gets copied in the order that it is poped
if (_array != null) {
Array.Copy (_array, 0, dest, idx, _size);
Array.Reverse (dest, idx, _size);
}
}
public T Peek ()
{
if (_size == 0)
throw new InvalidOperationException ();
return _array [_size - 1];
}
public T Pop ()
{
if (_size == 0)
throw new InvalidOperationException ();
_version ++;
T popped = _array [--_size];
// clear stuff out to make the GC happy
_array [_size] = default(T);
return popped;
}
public void Push (T t)
{
if (_array == null || _size == _array.Length)
Array.Resize <T> (ref _array, _size == 0 ? INITIAL_SIZE : 2 * _size);
_version ++;
_array [_size++] = t;
}
public T [] ToArray ()
{
T [] copy = new T [_size];
CopyTo (copy, 0);
return copy;
}
public void TrimExcess ()
{
if (_array != null && (_size < _array.Length * 0.9))
Array.Resize <T> (ref _array, _size);
_version ++;
}
public int Count {
get { return _size; }
}
bool ICollection.IsSynchronized {
get { return false; }
}
object ICollection.SyncRoot {
get { return this; }
}
void ICollection.CopyTo (Array dest, int idx)
{
try {
if (_array != null) {
_array.CopyTo (dest, idx);
Array.Reverse (dest, idx, _size);
}
} catch (ArrayTypeMismatchException) {
throw new ArgumentException ();
}
}
public Enumerator GetEnumerator ()
{
return new Enumerator (this);
}
IEnumerator <T> IEnumerable<T>.GetEnumerator ()
{
return GetEnumerator ();
}
IEnumerator IEnumerable.GetEnumerator ()
{
return GetEnumerator ();
}
[Serializable]
public struct Enumerator : IEnumerator <T>, IEnumerator, IDisposable {
const int NOT_STARTED = -2;
// this MUST be -1, because we depend on it in move next.
// we just decr the _size, so, 0 - 1 == FINISHED
const int FINISHED = -1;
Stack <T> parent;
int idx;
int _version;
internal Enumerator (Stack <T> t)
{
parent = t;
idx = NOT_STARTED;
_version = t._version;
}
// for some fucked up reason, MSFT added a useless dispose to this class
// It means that in foreach, we must still do a try/finally. Broken, very
// broken.
public void Dispose ()
{
idx = FINISHED;
}
public bool MoveNext ()
{
if (_version != parent._version)
throw new InvalidOperationException ();
if (idx == -2)
idx = parent._size;
return idx != FINISHED && -- idx != FINISHED;
}
public T Current {
get {
if (idx < 0)
throw new InvalidOperationException ();
return parent._array [idx];
}
}
void IEnumerator.Reset ()
{
if (_version != parent._version)
throw new InvalidOperationException ();
idx = NOT_STARTED;
}
object IEnumerator.Current {
get { return Current; }
}
}
}
}
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