Object-oriented programming
Significant object-oriented languages include Ada, ActionScript, C++, Common Lisp, C#, Dart, Eiffel, Fortran 2003, Haxe, Java,[4] JavaScript, Kotlin, Logo, MATLAB, Objective-C, Object Pascal, Perl, PHP, Python, R, Raku, Ruby, Scala, SIMSCRIPT, Simula, Smalltalk, Swift, Vala and Visual Basic.NET.
Terminology invoking "objects" in the modern sense of object-oriented programming made its first appearance at the artificial intelligence group at MIT in the late 1950s and early 1960s.
[7] Also, in 1968, an MIT ALGOL version, AED-0, established a direct link between data structures ("plexes", in that dialect) and procedures, prefiguring what were later termed "messages", "methods", and "member functions".
[8] Simula introduced important concepts that are today an essential part of object-oriented programming, such as class and object, inheritance, and dynamic binding.
[1] A 1976 MIT memo co-authored by Barbara Liskov lists Simula 67, CLU, and Alphard as object-oriented languages, but does not mention Smalltalk.
[13] In the 1970s, the first version of the Smalltalk programming language was developed at Xerox PARC by Alan Kay, Dan Ingalls and Adele Goldberg.
[17] In 1981, Goldberg edited the August issue of Byte Magazine, introducing Smalltalk and object-oriented programming to a wide audience.
[19] In 1986, the Association for Computing Machinery organized the first Conference on Object-Oriented Programming, Systems, Languages, and Applications (OOPSLA), which was attended by 1,000 people.
In the mid-1980s Objective-C was developed by Brad Cox, who had used Smalltalk at ITT Inc.. Bjarne Stroustrup, who had used Simula for his PhD thesis, created the object-oriented C++.
[20] Essential to the quality focus of Eiffel is Meyer's reliability mechanism, design by contract, which is an integral part of both the method and language.
Its dominance was further enhanced by the rising popularity of graphical user interfaces, which rely heavily upon object-oriented programming techniques.
Inheritance is not obvious in Wirth's design since his nomenclature looks in the opposite direction: It is called type extension and the viewpoint is from the parent down to the inheritor.
Probably the most commercially important recent object-oriented languages are Java, developed by Sun Microsystems, as well as C# and Visual Basic.NET (VB.NET), both designed for Microsoft's .NET platform.
The features listed below are common among languages considered to be strongly class- and object-oriented (or multi-paradigm with OOP support), with notable exceptions mentioned.
It's a strangely skewed perspective.Rich Hickey, creator of Clojure, described object systems as overly simplistic models of the real world.
[32] Alexander Stepanov compares object orientation unfavourably to generic programming:[31] I find OOP technically unsound.
Even if it is true it is not very interesting — saying that everything is an object is saying nothing at all.OOP languages typically allow inheritance for code reuse and extensibility in the form of either classes or prototypes.
Procedures and variables can be specific to either the class or the instance; this leads to the following terms: Depending on the definition of the language, subclasses may or may not be able to override the methods defined by superclasses.
In C#, Swift & Kotlin languages, internal keyword permits access only to files present in the same assembly, package, or module as that of the class.
[43] The latter point is reiterated by Joe Armstrong, the principal inventor of Erlang, who is quoted as saying:[44] The problem with object-oriented languages is they've got all this implicit environment that they carry around with them.
Concerning the degree of object orientation, the following distinctions can be made: Many widely used languages, such as C++, Java, and Python, provide object-oriented features.
[55] Eric S. Raymond, a Unix programmer and open-source software advocate, has been critical of claims that present object-oriented programming as the "One True Solution".
[49] Richard Feldman argues that these languages may have improved their modularity by adding OO features, but they became popular for reasons other than being object-oriented.
Design Patterns: Elements of Reusable Object-Oriented Software is an influential book published in 1994 by Erich Gamma, Richard Helm, Ralph Johnson, and John Vlissides, often referred to humorously as the "Gang of Four".
The book describes the following patterns: Both object-oriented programming and relational database management systems (RDBMSs) are extremely common in software today[update].
Since relational databases do not store objects directly (though some RDBMSs have object-oriented features to approximate this), there is a general need to bridge the two worlds.
[60] One of the most common approaches is object-relational mapping, as found in IDE languages such as Visual FoxPro and libraries such as Java Data Objects and Ruby on Rails' ActiveRecord.
However, Niklaus Wirth (who popularized the adage now known as Wirth's law: "Software is getting slower more rapidly than hardware becomes faster") said of OOP in his paper, "Good Ideas through the Looking Glass", "This paradigm closely reflects the structure of systems in the real world and is therefore well suited to model complex systems with complex behavior"[63] (contrast KISS principle).
Steve Yegge and others noted that natural languages lack the OOP approach of strictly prioritizing things (objects/nouns) before actions (methods/verbs).
With the increasing relevance of parallel hardware and multithreaded coding, developing transparent control flow becomes more important, something hard to achieve with OOP.
