introduction to web programming Inheritance in Perl Inheritance in Perl 5 is very simple. To do so, you simply declare a class array called @ISA. This array will be used to store the name and parent class(es) of the new species. Whenever the new class is used, it will have this reference to its lineage and be able to check there against method calls and properties.

For example, to define a subclass of Cat, you could use

     package NorthAmericanCat;
     @NorthAmericanCat::ISA = ("Cat");
     sub new {
             [. . . Code goes here . . .]
             }

Notice that in perl 5, package references are handled using the "::" notation. Finally, note that instantiation of an inherited class will work just the same as it did without inheritance.

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