Subclause
[tuple] describes the tuple library that provides a tuple type as
the class template
tuple that can be instantiated with any number
of arguments
.Each template argument specifies
the type of an element in the
tuple.Consequently, tuples are
heterogeneous, fixed-size collections of values
.A specialization of
tuple with
two arguments behaves similarly to a specialization of
pair with the same two arguments
.