Ranges Without Actual Elements

Flexibility of not actually owning elements

The elements of the School objects were actually stored in the students member slices. So, School.front returned a reference to an existing Student object.

One of the powers of ranges is the flexibility of not actually owning elements. For example, front does not need to return an actual element of an actual container. The returned element can be calculated each time when popFront() is called, and it can be used as the value that is returned by front.

You have already seen a range without actual elements. Since char and wchar cannot represent all Unicode characters, the Unicode characters that appear as range elements cannot be actual elements of any char or wchar array. In the case of strings, front returns a dchar that is constructed from the corresponding UTF code units of arrays: