public ProjectionDefinition<TSource> ElemMatch<TItem>(
	Expression<Func<TSource, IEnumerable<TItem>>> field,
	Expression<Func<TItem, bool>> filter
)

Public Function ElemMatch(Of TItem) ( 
	field As Expression(Of Func(Of TSource, IEnumerable(Of TItem))),
	filter As Expression(Of Func(Of TItem, Boolean))
) As ProjectionDefinition(Of TSource)

member ElemMatch : 
        field : Expression<Func<'TSource, IEnumerable<'TItem>>> * 
        filter : Expression<Func<'TItem, bool>> -> ProjectionDefinition<'TSource>