=== Object Oriented Reuse ===

=== [[SuperVsInner|Object Oriented Reuse]] ===

{{:SuperVsInner}}

{{:SuperVsInner}}

Last but not least the [http://www.cs.utexas.edu/~wcook/Drafts/2009/essay.pdf essay] mentions the [[expression problem]] which I also analysed in [[TheAPIBook]]'s chapter 18: [[Chapter 18|Extensible Visitor Pattern Case Study]].

Last but not least the [http://www.cs.utexas.edu/~wcook/Drafts/2009/essay.pdf essay] mentions the [[expression problem]] which I also analysed in [[TheAPIBook]]'s chapter 18: [[Chapter 18|Extensible Visitor Pattern Case Study]].

=== History ===

=== History ===

* In functional world (when using algebraic types) the person that defines a type can inspect internals of all instances of the same type

* In functional world (when using algebraic types) the person that defines a type can inspect internals of all instances of the same type

The above characteristic of [[OOP]] leads to an interesting conclussion: [[OOP]] needs [http://projectfortress.sun.com/Projects/Community/blog/ObjectOrientedTailRecursion tail recursion]!

The above characteristic of [[OOP]] leads to an interesting conclussion: [[OOP]] needs [http://projectfortress.sun.com/Projects/Community/blog/ObjectOrientedTailRecursion tail calls]!

Last but not least the [http://www.cs.utexas.edu/~wcook/Drafts/2009/essay.pdf essay] mentions the [[expression problem]] which I also analysed in [[TheAPIBook]]'s chapter 18: [[Chapter 18|Extensible Visitor Pattern Case Study]].

Last but not least the [http://www.cs.utexas.edu/~wcook/Drafts/2009/essay.pdf essay] mentions the [[expression problem]] which I also analysed in [[TheAPIBook]]'s chapter 18: [[Chapter 18|Extensible Visitor Pattern Case Study]].

* In classical [[OOP]] one only knows own identity. Identity (and implementation) of others can be inspected only by calling their methods (sending them messages)

* In classical [[OOP]] one only knows own identity. Identity (and implementation) of others can be inspected only by calling their methods (sending them messages)

* In functional world (when using algebraic types) the person that defines a type can inspect internals of all instances of the same type

* In functional world (when using algebraic types) the person that defines a type can inspect internals of all instances of the same type

Last but not least the [http://www.cs.utexas.edu/~wcook/Drafts/2009/essay.pdf essay] mentions the [[expression problem]] which I also analysed in [[TheAPIBook]]'s chapter 18: [[Chapter 18|Extensible Visitor Pattern Case Study]].

Last but not least the [http://www.cs.utexas.edu/~wcook/Drafts/2009/essay.pdf essay] mentions the [[expression problem]] which I also analysed in [[TheAPIBook]]'s chapter 18: [[Chapter 18|Extensible Visitor Pattern Case Study]].

Let me point you to [http://www.cs.utexas.edu/~wcook/Drafts/2009/essay.pdf an essay] explaining [[OOP]] in completely revolutionary view. I especially like statements like:

Let me point you to [http://www.cs.utexas.edu/~wcook/Drafts/2009/essay.pdf an essay] explaining [[OOP]] in completely revolutionary view. I especially like statements like:

* ''Typical object oriented program relies on functions more than many functional programs.''

* ''Typical object oriented program relies on functions more than many functional programs.''

* ''λ-calculus was the first [[OOP]] language''

* ''[[λ-calculus]] was the first [[OOP]] language''

Excellent explanation of the differences between [[OOP]] approach and the ''functional'' one can be summarized into:

Excellent explanation of the differences between [[OOP]] approach and the ''functional'' one can be summarized into:

Excellent explanation of the differences between [[OOP]] approach and the ''functional'' one can be summarized into:

Excellent explanation of the differences between [[OOP]] approach and the ''functional'' one can be summarized into:

* In classical [[OOP]] one only knows own identity. Identity (and implementation) of others can be inspected only calling their methods (sending them messages)

* In classical [[OOP]] one only knows own identity. Identity (and implementation) of others can be inspected only by calling their methods (sending them messages)

* In functional world (when using algebraic types) the person that defines a type can inspect internals of all instances of the same type

* In functional world (when using algebraic types) the person that defines a type can inspect internals of all instances of the same type

[[OOP]] is no longer what it used to be. Somehow the original great visions diluted and instead we have ''class''/''object''/''inheritance'' as present in [[Java]] and other [[OOP]] languages of these days. The daily experience we have with these languages is so strong, so defining that we sometimes tend to forget that the roots of [[OOP]] used to be driven by visions and not technical concepts.

[[OOP]] is no longer what it used to be. Somehow the original great visions diluted and instead we have ''class''/''object''/''inheritance'' as present in [[Java]] and other [[OOP]] languages of these days. The daily experience we have with these languages is so strong, so defining that we sometimes tend to forget that the roots of [[OOP]] used to be driven by visions and not technical concepts.

I was reminded about that recently when I read [http://www.artima.com/articles/dci_vision.html Motivation for DCI] at artima website. Just few quotes:

I was reminded about that recently when I read [[DCI]] introduction [http://www.artima.com/articles/dci_vision.html paper] at artima website. Just few quotes:

:''Object oriented programming grew out as vision of the computer''

:''Object oriented programming grew out as vision of the computer''

Excellent explanation of the differences between [[OOP]] approach and the ''functional'' one can be summarized into:

Excellent explanation of the differences between [[OOP]] approach and the ''functional'' one can be summarized into:

* In classical [[OOP]] one only knows own identity. Identity (and implementation) of others can be inspected only calling their methods (sending them messages)

* In classical [[OOP]] one only knows own identity. Identity (and implementation) of others can be inspected only calling their methods (sending them messages)

* In functional world (when using algebraic types) the person that defines a type can inspects and rely on internals of all instances of the same type

* In functional world (when using algebraic types) the person that defines a type can inspect internals of all instances of the same type

Last but not least the [http://www.cs.utexas.edu/~wcook/Drafts/2009/essay.pdf essay] mentions the [[expression problem]] which I also analysed in [[TheAPIBook]]'s chapter 18: [[Chapter 18|Extensible Visitor Pattern Case Study]].

Last but not least the [http://www.cs.utexas.edu/~wcook/Drafts/2009/essay.pdf essay] mentions the [[expression problem]] which I also analysed in [[TheAPIBook]]'s chapter 18: [[Chapter 18|Extensible Visitor Pattern Case Study]].

* In functional world (when using algebraic types) the person that defines a type can inspects and rely on internals of all instances of the same type

* In functional world (when using algebraic types) the person that defines a type can inspects and rely on internals of all instances of the same type

Last but not least the [http://www.cs.utexas.edu/~wcook/Drafts/2009/essay.pdf essay] mentions the [[expression problem]] which I also analysed in [[TheAPIBook]]'s chapter 18: [Chapter 18|Extensible Visitor Pattern Case Study].

Last but not least the [http://www.cs.utexas.edu/~wcook/Drafts/2009/essay.pdf essay] mentions the [[expression problem]] which I also analysed in [[TheAPIBook]]'s chapter 18: [[Chapter 18|Extensible Visitor Pattern Case Study]].

=== History ===

=== History ===

This is my personal take on [[OOP]]. In case you are searching for objective view, then rather see official [[wikipedia::Object_oriented_programming|wikipedia's explanation]].

This is my personal take on [[OOP]]. In case you are searching for objective view, then rather see official [[wikipedia::Object_oriented_programming|wikipedia's explanation]].

=== History ===

=== History ===