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Prototype Pattern
The prototype pattern is a creational design pattern (computer science), design pattern in software development. It is used when the types of object (computer science), objects to create is determined by a prototype, prototypical instance (computer science), instance, which is cloned to produce new objects. This pattern is used to avoid subclass (computer science), subclasses of an object creator in the client application, like the factory method pattern does, and to avoid the inherent cost of creating a new object in the standard way (e.g., using the 'new (C++), new' keyword) when it is prohibitively expensive for a given application. To implement the pattern, the client declares an abstract base class that specifies a virtual method#Abstract classes and pure virtual functions, pure virtual ''clone()'' method. Any class that needs a "polymorphism (computer science), polymorphic constructor (computer science), constructor" capability derives itself from the abstract base class, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Design Pattern (computer Science)
In software engineering, a software design pattern or design pattern is a general, reusable solution to a commonly occurring problem in many contexts in software design. A design pattern is not a rigid structure to be transplanted directly into source code. Rather, it is a description or a template for solving a particular type of problem that can be deployed in many different situations. Design patterns can be viewed as formalized best practices that the programmer may use to solve common problems when designing a software application or system. Object-oriented design patterns typically show relationships and interactions between classes or objects, without specifying the final application classes or objects that are involved. Patterns that imply mutable state may be unsuited for functional programming languages. Some patterns can be rendered unnecessary in languages that have built-in support for solving the problem they are trying to solve, and object-oriented patterns are no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C++23
C++23, formally ISO/IEC 14882:2024, is the current open standard for the C++ programming language that follows C++20. The final draft of this version is N4950. In February 2020, at the final meeting for C++20 in Prague, an overall plan for C++23 was adopted: planned features for C++23 were library support for coroutines, a modular standard library, executors, and networking. The first WG21 meeting focused on C++23 was intended to take place in Varna in early June 2020, but was cancelled due to the COVID-19 pandemic, as was the November 2020 meeting in New York and the February 2021 meeting in Kona, Hawaii. All meetings until November 2022 were virtual while the November 2022 meeting until the final meeting in February 2023 was hybrid. The standard was technically finalized by WG21 at the hybrid meeting in Issaquah in February 2023. Modern "Hello, world" Example After many library changes applied to the working draft, the new "Hello, world" program will be import std; ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Decorator Pattern
In object-oriented programming, the decorator pattern is a design pattern that allows behavior to be added to an individual object, dynamically, without affecting the behavior of other instances of the same class. The decorator pattern is often useful for adhering to the Single Responsibility Principle, as it allows functionality to be divided between classes with unique areas of concern as well as to the Open-Closed Principle, by allowing the functionality of a class to be extended without being modified. Decorator use can be more efficient than subclassing, because an object's behavior can be augmented without defining an entirely new object. Overview The ''decorator'' design pattern is one of the twenty-three well-known ''design patterns''; these describe how to solve recurring design problems and design flexible and reusable object-oriented software—that is, objects which are easier to implement, change, test, and reuse. The decorator pattern provides a flexible alterna ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Composite Pattern
In software engineering, the composite pattern is a partitioning design pattern (computer science), design pattern. The composite pattern describes a group of objects that are treated the same way as a single instance of the same type of object. The intent of a composite is to "compose" objects into tree structures to represent part-whole hierarchies. Implementing the composite pattern lets clients treat individual objects and compositions uniformly. Overview The Composite design pattern is one of the twenty-three well-known ''Design Patterns, GoF design patterns'' that describe how to solve recurring design problems to design flexible and reusable object-oriented software, that is, objects that are easier to implement, change, test, and reuse. Problems the Composite design pattern can solve * Represent a part-whole hierarchy so that clients can treat part and whole objects uniformly. * Represent a part-whole hierarchy as tree structure. When defining (1) Part objects and (2) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delegation (programming)
In computing or computer programming, delegation refers generally to one entity passing something to another entity,Barry Wilkinson, ''Grid Computing: Techniques and Applications'' (2009), p. 164, . and narrowly to various specific forms of relationships. These include: * Delegation (object-oriented programming), evaluating a member of one object (the receiver) in the context of another, original object (the sender). ** Delegation pattern, a design pattern implementing this feature. ** Forwarding (object-oriented programming), an often-confused technique where a sending object uses the corresponding member of another object, without the receiving object having any knowledge of the original, sending object. ** Object aggregation or consultation, general term for one object using another. * Delegation (computer security), one user or process allowing another user or process to use their credentials or permissions. * Delegate (CLI), a form of type-safe function pointer used by t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inheritance (object-oriented Programming)
In object-oriented programming, inheritance is the mechanism of basing an Object (computer science), object or Class (computer programming), class upon another object (Prototype-based programming, prototype-based inheritance) or class (Class-based programming, class-based inheritance), retaining similar implementation. Also defined as deriving new classes (#Subclasses and superclasses, sub classes) from existing ones such as super class or Fragile base class, base class and then forming them into a hierarchy of classes. In most class-based object-oriented languages like C++, an object created through inheritance, a "child object", acquires all the properties and behaviors of the "parent object", with the exception of: Constructor (object-oriented programming), constructors, destructors, operator overloading, overloaded operators and friend functions of the base class. Inheritance allows programmers to create classes that are built upon existing classes, to specify a new implementat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Singleton Pattern
In object-oriented programming, the singleton pattern is a software design pattern that restricts the instantiation of a class to a singular instance. It is one of the well-known "Gang of Four" design patterns, which describe how to solve recurring problems in object-oriented software. The pattern is useful when exactly one object is needed to coordinate actions across a system. More specifically, the singleton pattern allows classes to: * Ensure they only have one instance * Provide easy access to that instance * Control their instantiation (for example, hiding the constructors of a class) The term comes from the mathematical concept of a singleton. Common uses Singletons are often preferred to global variables because they do not pollute the global namespace (or their containing namespace). Additionally, they permit lazy allocation and initialization, whereas global variables in many languages will always consume resources. The singleton pattern can also be used as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Builder Pattern
The builder pattern is a design pattern that provides a flexible solution to various object creation problems in object-oriented programming. The builder pattern separates the construction of a complex object from its representation. It is one of the 23 classic design patterns described in the book ''Design Patterns'' and is sub-categorized as a creational pattern. Overview The builder design pattern solves problems like: * How can a class (the same construction process) create different representations of a complex object? * How can a class that includes creating a complex object be simplified? Creating and assembling the parts of a complex object directly within a class is inflexible. It commits the class to creating a particular representation of the complex object and makes it impossible to change the representation later independently from (without having to change) the class. The builder design pattern describes how to solve such problems: * Encapsulate creating and assemb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abstract Factory Pattern
The abstract factory pattern in software engineering is a design pattern that provides a way to create families of related objects without imposing their concrete classes, by encapsulating a group of individual factories that have a common theme without specifying their concrete classes. According to this pattern, a client software component creates a concrete implementation of the abstract factory and then uses the generic interface of the factory to create the concrete objects that are part of the family. The client does not know which concrete objects it receives from each of these internal factories, as it uses only the generic interfaces of their products. This pattern separates the details of implementation of a set of objects from their general usage and relies on object composition, as object creation is implemented in methods exposed in the factory interface. Use of this pattern enables interchangeable concrete implementations without changing the code that uses them, ev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Creational Pattern
In software engineering, creational design patterns are design patterns that deal with object creation Object may refer to: General meanings * Object (philosophy), a thing, being, or concept ** Object (abstract), an object which does not exist at any particular time or place ** Physical object, an identifiable collection of matter * Goal, an a ... mechanisms, trying to create objects in a manner suitable to the situation. The basic form of object creation could result in design problems or in added complexity to the design due to inflexibility in the creation procedures. Creational design patterns solve this problem by somehow controlling this object creation. Overview Creational design patterns are composed of two dominant ideas. One is encapsulating knowledge about which concrete classes the system uses. Another is hiding how instances of these concrete classes are created and combined. Creational design patterns are further categorized into object-creational patterns ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prototype UML
A prototype is an early sample, model, or release of a product built to test a concept or process. It is a term used in a variety of contexts, including semantics, design, electronics, and software programming. A prototype is generally used to evaluate a new design to enhance precision by system analysts and users. Prototyping serves to provide specifications for a real, working system rather than a theoretical one. Physical prototyping has a long history, and paper prototyping and virtual prototyping now extensively complement it. In some design workflow models, creating a prototype (a process sometimes called materialization) is the step between the formalization and the evaluation of an idea. A prototype can also mean a typical example of something such as in the use of the derivation prototypical. This is a useful term in identifying objects, behaviours and concepts which are considered the accepted norm and is analogous with terms such as stereotypes and archetypes. The w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
