public static class EnumerableFns

<ExtensionAttribute>
Public NotInheritable Class EnumerableFns

[ExtensionAttribute]
public ref class EnumerableFns abstract sealed

[<AbstractClassAttribute>]
[<SealedAttribute>]
[<ExtensionAttribute>]
type EnumerableFns =  class end

The EnumerableFns type exposes the following members.

	Name	Description
	AllEqualT(IEnumerableT)	Returns true if all items in a cached collection are equal.
	AllEqualT, U(IEnumerableT, FuncT, U)	Returns true if all items in a cached collection have the same projected value.
	DistinctTSource, TResult	Returns distinct elements from a sequence by using a specified selector function to project objects to compare.
	ExceptTSource, TResult	Produces the set difference of two sequences by using a specified selector function to compare values.
	ForEachT(IEnumerableT, ActionT)	Enumerate a cached collection performing the specified action on each item.
	ForEachT(IEnumerableT, ActionT, Int32)	Enumerate an indexed collection in cache performing the specified action on each item.
	GetAggregateHashCode	Returns a hashcode for a collection that uses a similar algorithm to that used by the .NET Tuple class. Order matters.
	IndexOfT	Returns the index of the first item in the sequence matching a condition, or -1 if no match found.
	IntersectTSource, TResult	Produces the set intersection of two sequences by using a specified selector function to project objects to compare.
	ToAggregateString	Concatenates the string version of each element in a collection using the delimiter provided.
	ToHashSetT	Returns a HashSetT of the specified collection.
	UnionTSource, TResult	Produces the set union of two sequences by using a specified selector function to project objects to compare.

Since the methods here are extensions, you cannot use them in queries which will be sent to the data source,

For more information on extension methods, see Extension Methods (C# Programming Guide) or Extension Methods (Visual Basic) in the Visual Studio documentation.

Reference