Common auxiliary method set-Enumerable

Here are some common auxiliary methods for the Enumerable type. For other types, see the Directory: Use the C #3.0 Extensions method-and common auxiliary method set.

The code is listed directly here.

public static class EnumerableExtension{    public static void ForEach<T>(this IEnumerable<T> enumerable, Action<T> action)    {        Expect.ArgumentNotNull(action, "action");        foreach (T t in enumerable)        {            action(t);        }    }    public static void ForEach<T>(this IEnumerable<T> enumerable, Action<T, int> action)    {        Expect.ArgumentNotNull(action, "action");        int i = 0;        foreach (T t in enumerable)        {            action(t, i++);        }    }    /// <summary> Join the enumerable to a string.</summary>    public static string Join<T>(this IEnumerable<T> enumerable, string start, string end, string seperator)    {        return Join<T>(enumerable, start, end, seperator, e => e);    }    /// <summary> Join the enumerable to a string.</summary>    public static string Join<T>(this IEnumerable<T> enumerable, string start, string end, string seperator, Func<T, object> converter)    {        Expect.ArgumentNotNull(converter, "converter");        StringBuilder sb = new StringBuilder();        sb.Append(start);        enumerable.ForEach((e, i) => sb.AppendFormat("{0}{1}", i == 0 ? string.Empty : seperator, converter(e)));        sb.Append(end);        return sb.ToString();    }    /// <summary>    /// Generate an enumerable by repeating the given delegate.    /// </summary>    public static IEnumerable<T> Repeat<T>(this Func<T> generateResultFunc, int count)    {        for (int i = 0; i < count; ++i)        {            yield return generateResultFunc();        }    }    public static IDictionary<TKey, TValue> Clone<TKey, TValue>(this IDictionary<TKey, TValue> source)    {        Dictionary<TKey, TValue> dict = source as Dictionary<TKey, TValue>;        if (dict != null)        {            return new Dictionary<TKey, TValue>(source, dict.Comparer);        }        SortedDictionary<TKey, TValue> sortedDict = source as SortedDictionary<TKey, TValue>;        if (sortedDict != null)        {            return new SortedDictionary<TKey, TValue>(source, sortedDict.Comparer);        }        SortedList<TKey, TValue> sortedList = source as SortedList<TKey, TValue>;        if (sortedList != null)        {            return new SortedList<TKey, TValue>(source, sortedList.Comparer);        }        return new Dictionary<TKey, TValue>(source);    }    public static IList<T> Clone<T>(this IList<T> source)    {        return new List<T>(source);    }    public static Stack<T> Clone<T>(this Stack<T> source)    {        return new Stack<T>(source.Reverse());    }    public static Queue<T> Clone<T>(this Queue<T> source)    {        return new Queue<T>(source);    }    /// <summary>Merge the two dictionary. </summary>    public static void Merge<TKey, TValue>(this IDictionary<TKey, TValue> left, IDictionary<TKey, TValue> right)    {        Expect.ArgumentNotNull(left, "left");        Expect.ArgumentNotNull(right, "right");        foreach (var kvp in right)        {            left[kvp.Key] = kvp.Value;        }    }}