/// <summary>
/// Returns the next element of <paramref name="elements"/> relative to <paramref name="index"/>, or the last element of <paramref name="elements"/> if <paramref name="index"/> is equal or greater than <see cref="ICollection{T}.Count"/>.
/// </summary>
/// <typeparam name="TSource">The type of elements in the <see cref="IList{T}"/>.</typeparam>
/// <param name="elements">The elements, relative to <paramref name="index"/>, to return the next element of.</param>
/// <param name="index">The index of which to advance to the next element from.</param>
/// <exception cref="ArgumentOutOfRangeException">
/// <paramref name="index"/> is less than 0.
/// </exception>
/// <returns>default(TSource) if <paramref name="index"/> is equal or greater than <see cref="ICollection{T}.Count"/>; otherwise the next element of <paramref name="elements"/> relative to <paramref name="index"/>.</returns>
public static TSource Next <TSource>(this IList <TSource> elements, int index)
{
return(ListUtility.Next(index, elements));
}
/// <summary>
/// Returns the previous element of <paramref name="elements"/> relative to <paramref name="index"/>, or the first or last element of <paramref name="elements"/> if <paramref name="index"/> is equal, greater or lower than <see cref="ICollection{T}.Count"/>.
/// </summary>
/// <typeparam name="TSource">The type of elements in the <see cref="IList{T}"/>.</typeparam>
/// <param name="elements">The elements, relative to <paramref name="index"/>, to return the previous element of.</param>
/// <param name="index">The index of which to advance to the previous element from.</param>
/// <exception cref="ArgumentOutOfRangeException">
/// <paramref name="index"/> is less than 0.
/// </exception>
/// <returns>default(TSource) if <paramref name="index"/> is equal, greater or lower than <see cref="ICollection{T}.Count"/>; otherwise the previous element of <paramref name="elements"/> relative to <paramref name="index"/>.</returns>
public static TSource Previous <TSource>(this IList <TSource> elements, int index)
{
return(ListUtility.Previous(index, elements));
}
/// <summary>
/// Determines whether the <paramref name="elements"/> of the <see cref="IList{T}"/> is within the range of the <paramref name="index"/>.
/// </summary>
/// <typeparam name="TSource">The type of elements in the <see cref="IList{T}"/>.</typeparam>
/// <param name="elements">The elements of the <see cref="IList{T}"/>.</param>
/// <param name="index">The index to find.</param>
/// <returns><c>true</c> if the specified <paramref name="index"/> is within the range of the <paramref name="elements"/>; otherwise, <c>false</c>.</returns>
/// <exception cref="System.ArgumentNullException">
/// <paramref name="elements"/> is null.
/// </exception>
public static bool HasIndex <TSource>(this IList <TSource> elements, int index)
{
return(ListUtility.HasIndex(index, elements));
}
