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In computer science, abstract interpretation is a theory of sound approximation of the semantics of computer programs, based on monotonic functions over ordered sets, especially lattices. It can be viewed as a partial execution of a computer program which gains information about its semantics (e.g., control-flow , data-flow ) without performing ...
The abstract properties are those that are visible to client code that makes use of the data type—the interface to the data type—while the concrete implementation is kept entirely private, and indeed can change, for example to incorporate efficiency improvements over time. The idea is that such changes are not supposed to have any impact on ...
Abstraction is a process where general rules and concepts are derived from the use and classifying of specific examples, literal (real or concrete) signifiers, first principles, or other methods. "An abstraction" is the outcome of this process — a concept that acts as a common noun for all subordinate concepts and connects any related ...
For example, geometry has its origins in the calculation of distances and areas in the real world, and algebra started with methods of solving problems in arithmetic. Abstraction is an ongoing process in mathematics and the historical development of many mathematical topics exhibits a progression from the concrete to the abstract.
In object-oriented programming, the factory method pattern is a design pattern that uses factory methods to deal with the problem of creating objects without having to specify their exact classes. Rather than by calling a constructor , this is accomplished by invoking a factory method to create an object.
An abstract class is either labeled as such explicitly or it may simply specify abstract methods (or virtual methods). An abstract class may provide implementations of some methods, and may also specify virtual methods via signatures that are to be implemented by direct or indirect descendants of the abstract class. Before a class derived from ...
For example, when extending the definition of an abstract variable to include abstract records, operations upon a field F of a record variable R, clearly involve F, which is distinct from, but also a part of, R. A partial aliasing axiom would state that changing a field of one record variable does not affect any other records.
Often, abstract types will have one or more implementations provided separately, for example, in the form of concrete subtypes that can be instantiated. In object-oriented programming, an abstract class may include abstract methods or abstract properties [2] that are shared by its subclasses.