public static IEnumerable<TSource> Assert<TSource>(
	this IEnumerable<TSource> source,
	Func<TSource, bool> predicate,
	Func<TSource, Exception> errorSelector
)

<ExtensionAttribute>
Public Shared Function Assert(Of TSource) ( 
	source As IEnumerable(Of TSource),
	predicate As Func(Of TSource, Boolean),
	errorSelector As Func(Of TSource, Exception)
) As IEnumerable(Of TSource)

public:
[ExtensionAttribute]
generic<typename TSource>
static IEnumerable<TSource>^ Assert(
	IEnumerable<TSource>^ source, 
	Func<TSource, bool>^ predicate, 
	Func<TSource, Exception^>^ errorSelector
)

[<ExtensionAttribute>]
static member Assert : 
        source : IEnumerable<'TSource> * 
        predicate : Func<'TSource, bool> * 
        errorSelector : Func<'TSource, Exception> -> IEnumerable<'TSource>