Useful IList Extensions for C#/.Net

ListExtensions.cs

using System;
using System.Collections.Generic;

public static class ListExtensions
{
    public static TList Populate<TList, TElem>(this TList list, TElem defaultValue) where TList : IList<TElem>
    {
        for (int i = 0; i < list.Count; i++) {
            list[i] = defaultValue;
        }

        return list;
    }

    public static TList KnuthShuffle<TList>(this TList list) where TList : IList
    {
        for (int i = list.Count - 1; i > 0; i--)
        {
            int n = Random.Range(0, i);
            list.Swap(i, n);
        }
        return list;
    }

    public static void Swap<T>(this T list, int i1, int i2) where T : IList
    {
        var temp = list[i1];
        list[i1] = list[i2];
        list[i2] = temp;
    }

    public static T GetClamped<T>(this IList<T> list, int index)
    {
        if (index >= list.Count) {
            index = list.Count - 1;
        } else if (index < 0) {
            index = 0;
        }

        return list[index];
    }

    public static int WrapIndex<T>(this IList<T> list, int index)
    {
        int len = list.Count;
        return ((index % len) + len) % len;
    }

    public static T GetWrapped<T>(this IList<T> list, int index)
    {
        return list[list.WrapIndex(index)];
    }

    public static T GetWrapped<T>(this IList<T> list, ref int index)
    {
        index = list.WrapIndex(index);
        return list[index];
    }

    public static T Pop<T>(this List<T> list)
    {
        int lastIndex = list.Count - 1;
        T top = list[lastIndex];
        list.RemoveAt(lastIndex);
        return top;
    }

    public static T SwapAndPop<T>(this List<T> list, int indexToRemove)
    {
        list.Swap(indexToRemove, list.Count - 1);
        return list.Pop();
    }
    public static T SwapAndPop<T>(this List<T> list, T item)
    {
        int indexToRemove = list.IndexOf(item);
        return list.SwapAndPop(indexToRemove);
    }
}