public static bool Exactly<T>(
	this IEnumerable<T> source,
	int count
)

<ExtensionAttribute>
Public Shared Function Exactly(Of T) ( 
	source As IEnumerable(Of T),
	count As Integer
) As Boolean

public:
[ExtensionAttribute]
generic<typename T>
static bool Exactly(
	IEnumerable<T>^ source, 
	int count
)

[<ExtensionAttribute>]
static member Exactly : 
        source : IEnumerable<'T> * 
        count : int -> bool 

var numbers = { 123, 456, 789 };
var result = numbers.Exactly(3);