On Algebraic Properties of Nominative Data and Functions

In the chapter basic properties of nominative data and functions over nominative data (nominative functions) are investigated from the perspective of abstract algebra. A set of all nominative data over arbitrary fixed sets of names and values together with basic operations which include naming, denaming, and overlapping is considered as an algebraic structure and its main properties are studied. Nominative data with complex names satisfy the principle of associative naming and processing. For such data a natural equivalence relation is introduced. Properties of nominative functions (mathematical models of programs over nominative data) and predicates are studied. A notion of nominative stability of nominative functions and predicates is considered. A two-sorted algebra of nominative functions and predicates which generalizes Glushkov algorithmic algebras is introduced and it is proved that the set of nominative stable functions and the set of nominative stable predicates constitute its sub-algebra. The obtained results form a mathematical basis for nominative program logic construction.