TYPE-CHECKING MECHANISM for PLS3 or PLAS ABSTRACT DATA TYPES
Original Publication Date: 1987-Oct-01
Included in the Prior Art Database: 2005-Feb-02
In order to avoid obscure results being given as a result of the inappropriate level of diagnostics being applied to supposed irregularities in the presentation of abstract data types, variables which are of abstract data types are declared by macros. An abstract data type can be implemented as a collection of macros. For instance, a set of macros to implement SET might include facilities to DECLARE A SET (as AUTOMATIC, STATIC, BASED, PARAMETER or "included in a structure") INITIALIZE A SET (i.e., establish any invariants). CLEAR A SET. ADD AN ELEMENT TO A SET. FORM THE UNION OF TWO SETS. TEST WHETHER AN ELEMENT IS IN A SET. DELETE AN ELEMENT FROM A SET. FORM THE DIFFERENCE OF TWO SETS. FORM THE INTERSECTION OF TWO SETS. ITERATE THROUGH THE ELEMENTS OF A SET.