public static IEnumerable<TSource> Except<TSource, TResult>(
	this IEnumerable<TSource> first,
	IEnumerable<TSource> second,
	Func<TSource, TResult> selector
)

<ExtensionAttribute>
Public Shared Function Except(Of TSource, TResult) ( 
	first As IEnumerable(Of TSource),
	second As IEnumerable(Of TSource),
	selector As Func(Of TSource, TResult)
) As IEnumerable(Of TSource)

public:
[ExtensionAttribute]
generic<typename TSource, typename TResult>
static IEnumerable<TSource>^ Except(
	IEnumerable<TSource>^ first, 
	IEnumerable<TSource>^ second, 
	Func<TSource, TResult>^ selector
)

[<ExtensionAttribute>]
static member Except : 
        first : IEnumerable<'TSource> * 
        second : IEnumerable<'TSource> * 
        selector : Func<'TSource, 'TResult> -> IEnumerable<'TSource>