The at-views of the form T@L for types T and addresses L are building blocks for constructing other forms of views. One mechanism for putting together such building blocks is by declaring dataviews, which is mostly identical to declaring dataprops. I now present in this chapter some commonly encountered dataviews and their uses.
Please find on-line the code presented for illustration in this chapter.
The dataview option_v is declared as follows:
As an example, the following function interface involves a typical use of optional view: