MoreEnumerableFallbackIfEmptyT Method (IEnumerableT, T)

public static IEnumerable<T> FallbackIfEmpty<T>(
	this IEnumerable<T> source,
	T fallback
)

<ExtensionAttribute>
Public Shared Function FallbackIfEmpty(Of T) ( 
	source As IEnumerable(Of T),
	fallback As T
) As IEnumerable(Of T)

public:
[ExtensionAttribute]
generic<typename T>
static IEnumerable<T>^ FallbackIfEmpty(
	IEnumerable<T>^ source, 
	T fallback
)

[<ExtensionAttribute>]
static member FallbackIfEmpty : 
        source : IEnumerable<'T> * 
        fallback : 'T -> IEnumerable<'T> 

var numbers = new[] { 123, 456, 789 };
var result = numbers.Where(x => x == 100).FallbackIfEmpty(-1).Single();