//
// System.Text.RegularExpressions.MatchCollection
//
// Authors:
// Dan Lewis (dlewis@gmx.co.uk)
// Dick Porter (dick@ximian.com)
//
// (C) 2002 Dan Lewis
// (C) 2004 Novell, Inc.
//
//
// 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.Collections;
namespace System.Text.RegularExpressions{
[Serializable]
public class MatchCollection: ICollection, IEnumerable {
private Match current;
// Stores all the matches before 'current'. If !current.Success, it has all the successful matches.
private ArrayList list;
/* No public constructor */
internal MatchCollection (Match start)
{
current = start;
list = new ArrayList ();
}
public int Count {
get { return FullList.Count; }
}
public bool IsReadOnly {
get { return true; }
}
public bool IsSynchronized {
get { return false; }
}
public virtual Match this [int i] {
get {
if (i < 0 || !TryToGet (i))
throw new ArgumentOutOfRangeException ("i");
return i < list.Count ? (Match) list [i] : current;
}
}
public object SyncRoot {
get { return list; }
}
public void CopyTo (Array array, int index)
{
FullList.CopyTo (array, index);
}
public IEnumerator GetEnumerator ()
{
// If !current.Success, the list is fully populated. So, just use it.
return current.Success ? new Enumerator (this) : list.GetEnumerator ();
}
// Returns true when: i < list.Count => this [i] == list [i]
// i == list.Count && current.Success => this [i] == current
private bool TryToGet (int i)
{
while (i > list.Count && current.Success) {
list.Add (current);
current = current.NextMatch ();
}
// Here we have: !(i > list.Count && current.Success)
// or in a slightly more useful form: i > list.Count => current.Success == false
return i < list.Count || current.Success;
}
private ICollection FullList {
get {
if (TryToGet (Int32.MaxValue)) {
// list.Count == Int32.MaxValue && current.Success
// i.e., we have more than Int32.MaxValue matches.
// We can't represent that number with Int32.
throw new SystemException ("too many matches");
}
return list;
}
}
class Enumerator : IEnumerator {
int index;
MatchCollection coll;
internal Enumerator (MatchCollection coll)
{
this.coll = coll;
index = -1;
}
void IEnumerator.Reset ()
{
index = -1;
}
object IEnumerator.Current {
get {
if (index < 0)
throw new InvalidOperationException ("'Current' called before 'MoveNext()'");
if (index > coll.list.Count)
throw new SystemException ("MatchCollection in invalid state");
if (index == coll.list.Count && !coll.current.Success)
throw new InvalidOperationException ("'Current' called after 'MoveNext()' returned false");
return index < coll.list.Count ? coll.list [index] : coll.current;
}
}
bool IEnumerator.MoveNext ()
{
if (index > coll.list.Count)
throw new SystemException ("MatchCollection in invalid state");
if (index == coll.list.Count && !coll.current.Success)
return false;
return coll.TryToGet (++index);
}
}
}
}
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