Abstract type: Difference between revisions

For example in [[object-oriented programming]] abstract types can be in some languages a partial implementation of other types, which are later derived from it. Abstract type may provide implementation of some operations and/or components. Abstract types without any implementation are called '''interfaces'''. In the languages that do not support multiple [[inheritance]] ([[Ada]], [[Java]]), interfaces are usually allowed to be multiply inherited from. The languages with multiple inheritance (like [[C++]]) usually make no distinction between partially implementable abstract types and interfaces. Because the abstract type's implementation is incomplete, if any, it makes no sense to have any instances (objects) of it. Therefore an [[object-oriented programming | OO]] language would prevent creation of such objects.

 

 

'''Task''': show how an abstract type can be declared in the language. If the language makes a distinction between interfaces and partially implemented types illustrate both.