You can access a Unicode scalar representation of a String value by iterating over its
unicodeScalars property. This property is of type UnicodeScalarView, which is a collection of values
of type UnicodeScalar. A Unicode scalar is any 21-bit Unicode code point that is not a lead
surrogate or trail surrogate code point.
Each UnicodeScalar has a value property that returns the scalar’s 21-bit value, represented
within a UInt32 value: