/// <summary>
/// Requires that the provided object is actually of the type required.
/// </summary>
/// <param name="actual">The object to verify.</param>
/// <param name="paramName">Name of the parameter as passed into the checking method.</param>
/// <param name="allowNull">
/// If <see langword="true"/> and <typeparamref name="T"/> can be null, returns null rather than throwing when <paramref name="actual"/> is null.
/// If <typeparamref name="T"/> cannot be null, this parameter is ignored.</param>
/// <typeparam name="T">The type to require.</typeparam>
public static T RequireActual <T>(object actual, string paramName, bool allowNull = false)
{
if (TypeHelper.TryCast(actual, out T result) && (allowNull || result != null))
{
return(result);
}
var actualDisplay = actual == null ? "null" : actual.GetType().Name;
throw new ArgumentException($"Expected: {typeof(T).Name} But was: {actualDisplay}", paramName);
}
