python:python_misc:oo_fundamentals_with_python
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python:python_misc:oo_fundamentals_with_python [2018/08/23 17:07] – [Class-based object-orientation] mithat | python:python_misc:oo_fundamentals_with_python [2018/11/30 18:45] (current) – [Instantiation and use] mithat | ||
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==== Behavior ==== | ==== Behavior ==== | ||
- | A given microwave oven also has predefined **behavior**. | + | A given microwave oven also has predefined **behavior**: |
* //Push the " | * //Push the " | ||
- | * //Push the " | + | * //Push the " |
* //Push a magical combination of buttons// → set the internal clock. | * //Push a magical combination of buttons// → set the internal clock. | ||
* And so on. | * And so on. | ||
- | These operations are ones that happen to be public-facing (i.e., operations a user can engage). There might very well also be operations that go on inside the oven to support the oven's functioning | + | These operations are ones that happen to be public-facing (i.e., operations a user can engage). There might very well also be operations that go on inside the oven that the user will never be aware of to support |
==== Encapsulation and protection ==== | ==== Encapsulation and protection ==== | ||
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{{: | {{: | ||
- | Because OOP models itself after real-world objects, we're going to use a real-world | + | I have a Farberware 4241 microwave oven in my office. It's small, but it gets the job done. There is a factory somewhere making these by the thousand million. They make all the Farberware 4241s from a master plan, a plan that defines what the Farberware 4241 //is//. In object-oriented design terminology, we would call that master plan a **class**. A class contains all the specifications needed |
- | I have a Farberware 4241 microwave oven in my office. It's small, but it gets the job done. There is a factory somewhere making these by the thousand million, and they make all the Farberware 4241s from a master plan. That master plan defines what the Farberware 4241 //is//. In computing terminology, | + | Languages that support **class-based object-oriented programming** let you define classes at a very high level. Once you've defined |
- | Every Farberware 4241 begins its life identical to every other freshly-made Farberware 4241 because they were made using the same master plan. So, the one in my office that I pulled out of the box last month was identical to the one that I bought my best friend last week later because they were built from the same master plan, or, if you will, the same class. But as my best friend and I started using our ovens, the state of each changed. Note that while the behavior designed into the oven---the operations it's capable of---doesn' | + | Thus my oven is an instance of a Farberware 4241, and you might say the Farberware factory spends it's entire day instantiating 4241 ovens. |
- | + | ||
- | In **class-based object-oriented programming**, | + | |
==== Prototype-based object-orientation ==== | ==== Prototype-based object-orientation ==== | ||
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)) \\ {{..: | )) \\ {{..: | ||
- | In case you've never seen this bit of advanced technology before, it's a clicker-counter or tally-counter. It has two controls: a button you click to advance the counter by one and another you press to reset the count to zero. Our goal is to build one of these in software using object-orientation. | + | In case you've never seen one of these bits of advanced technology before, it's a clicker-counter or tally-counter. It has two controls: a button you click to advance the counter by one and another you press to reset the count to zero. Our goal is to build one of these in software using object-orientation. |
One way to start building a model for a class is to start listing the public-facing behavior (or the // | One way to start building a model for a class is to start listing the public-facing behavior (or the // | ||
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a.click(self) | a.click(self) | ||
</ | </ | ||
- | Python' | + | Python' |
==== Parameterized constructors and methods ==== | ==== Parameterized constructors and methods ==== | ||
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==== Next steps ==== | ==== Next steps ==== | ||
- | This just scratches the surface of what's possible with object-oriented programming. In particular, we haven' | + | This just scratches the surface of what's possible with object-oriented programming. In particular, we haven' |
Copyright © 2011-2018 Mithat Konar. All rights reserved. | Copyright © 2011-2018 Mithat Konar. All rights reserved. |
python/python_misc/oo_fundamentals_with_python.1535044070.txt.gz · Last modified: 2018/08/23 17:07 by mithat