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Just like most other object-oriented languages, Pike has classes,
objects, inheritance, constructors, and so on. In Pike, a source file
can be used as a class definition. Class and program are
synonyms.
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Programs Within Programs: Object-Oriented Pike
As we have said before, a class is a description of a type
of thing. You can clone the class to create objects.
Each object is a clone (sometimes called instance) of
the class.
A class contains some variables, which are sometimes called
member variables. The variables are attributes or
characteristics of the objects, and each object will have its own set
of the member variables. For example, if the class animal has
the member variables name and weight, then each
animal will have those two variables, so each animal can have a name
and a weight.
A class also contains some methods. (C++ programmers would call
them "member functions".) The methods describe things that the objects
can do.
For example, if the class "animal" has the method eat,
then you can call that method in any animal, to make it eat. Well, of
course it won't really eat, since it's just some data in the computer
and not a real animal. But the method can change the member variables,
for example by increasing the value of weight for that
animal.
