/*
[The "BSD licence"]
Copyright (c) 2005 Kunle Odutola
Copyright (c) 2003-2005 Terence Parr
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
3. The name of the author may not be used to endorse or promote products
derived from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
namespace Antlr.StringTemplate.Collections{
using System;
using IList = System.Collections.IList;
using IDictionary = System.Collections.IDictionary;
using DictionaryEntry = System.Collections.DictionaryEntry;
using IEnumerator = System.Collections.IEnumerator;
using StringBuilder = System.Text.StringBuilder;
internal class CollectionUtils
{
/// <summary>
/// Returns a string representation of this IList.
/// </summary>
/// <remarks>
/// The string representation is a list of the collection's elements in the order
/// they are returned by its IEnumerator, enclosed in square brackets ("[]").
/// The separator is a comma followed by a space i.e. ", ".
/// </remarks>
/// <param name="coll">Collection whose string representation will be returned</param>
/// <returns>A string representation of the specified collection or "null"</returns>
public static string ListToString(IList coll)
{
StringBuilder sb = new StringBuilder();
if (coll != null)
{
sb.Append("[");
for (int i = 0; i < coll.Count; i++)
{
if (i > 0)
sb.Append(", ");
if (coll[i] == null)
sb.Append("null");
else
sb.Append(coll[i].ToString());
}
sb.Append("]");
}
else
sb.Insert(0, "null");
return sb.ToString();
}
/// <summary>
/// Returns a string representation of this IList.
/// </summary>
/// <remarks>
/// The string representation is a list of the collection's elements in the order
/// they are returned by its IEnumerator, enclosed in square brackets ("[]").
/// The separator is a comma followed by a space i.e. ", ".
/// </remarks>
/// <param name="coll">Collection whose string representation will be returned</param>
/// <returns>A string representation of the specified collection or "null"</returns>
public static string DictionaryToString(IDictionary dict)
{
StringBuilder sb = new StringBuilder();
if (dict != null)
{
sb.Append("{");
int i = 0;
foreach (DictionaryEntry e in dict)
{
if (i > 0)
{
sb.Append(", ");
}
sb.AppendFormat("{0}={1}", e.Key.ToString(), e.Value.ToString());
i++;
}
sb.Append("}");
}
else
sb.Insert(0, "null");
return sb.ToString();
}
/// <summary>
/// Tests whether an IEnumerator is "empty", leaving IEnumerator at same position
/// </summary>
/// <param name="enumerator">IEnumerator instance to test</param>
/// <returns>True if enumerator is empty, false otherwise</returns>
public static bool IsEmptyEnumerator(IEnumerator enumerator)
{
try
{
object o = enumerator.Current;
return false;
}
catch (InvalidOperationException)
{
// We are either at the start of a collection or, lumbered with an invalid enumerator
try
{
if (enumerator.MoveNext())
{
// put it back to start of list
enumerator.Reset();
return false;
}
}
catch (InvalidOperationException)
{
// lumbered with a dead duck
}
}
return true;
}
}
}
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