Editing Multiple inheritance (section)

{{Short description|In software, to have several parent classes}}
{{More citations needed|date=August 2012}}
'''Multiple inheritance''' is a feature of some [[object-oriented programming|object-oriented]] computer [[programming language]]s in which an object or [[class (computer programming)|class]] can [[inheritance (object-oriented programming)|inherit]] features from more than one parent object or [[superclass (computer science)|parent class]]. It is distinct from single inheritance, where an object or class may only inherit from one particular object or class.

Multiple inheritance has been a controversial issue for many years,<ref>{{cite journal |last=Cargill |first=T. A. |date=Winter 1991 |title=Controversy: The Case Against Multiple Inheritance in C++ |journal=Computing Systems |volume=4 |number=1 |pages=69–82}}</ref><ref>{{cite journal |last=Waldo |first=Jim |date=Spring 1991 |title=Controversy: The Case For Multiple Inheritance in C++ |journal=Computing Systems |volume=4 |number=2 |pages=157–171}}</ref> with opponents pointing to its increased complexity and ambiguity in situations such as the "diamond problem", where it may be ambiguous as to which parent class a particular feature is inherited from if more than one parent class implements said feature. This can be addressed in various ways, including using [[virtual inheritance]].<ref>{{cite web |last1=Schärli |first1=Nathanael |last2=Ducasse |first2=Stéphane |last3=Nierstrasz |first3=Oscar |last4=Black |first4=Andrew |title=Traits: Composable Units of Behavior |website=Web.cecs.pdx.edu |url=http://web.cecs.pdx.edu/~black/publications/TR_CSE_02-012.pdf |format=PDF |access-date=2016-10-21}}</ref> Alternate methods of [[object composition]] not based on inheritance such as [[mixin]]s and [[trait (computer programming)|traits]] have also been proposed to address the ambiguity.