public static ValidateTarget<bool?> IsFalse([ValidatedNotNull] this ValidateTarget<bool?> target, Func<string> getErrorMessage = null)
{
if (!target.Value.HasValue || target.Value.Value)
{
ExceptionFactory.ThrowException(target.Traits.GenericFailureExceptionType, getErrorMessage != null ? getErrorMessage.Invoke() : ErrorMessageFactory.ShouldBeFalse(target));
}
return target;
}