59 lines
1.3 KiB
D
59 lines
1.3 KiB
D
module inheritance;
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// ****** interfaces ******
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// 1) its member functions are abstract (have no implementation)
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// 2) interfaces can inherit only form other interfaces
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// 3) inheritance syntax => interface/class Name: Inherit_Name {}
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interface IAnimal {
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void makeSound(); // abstract function ('abstract' keyword could be used in a class to achieve the same functionality)
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// ...
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//static/final type name() { ... } // static and final members do have an implementation, are inherited, and cannot be overriden
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}
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// ****** inheritance ******
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// 1) interfaces can inherit only from other interfaces
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// 2) classes can inherit from multiple interfaces
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// 3) interface members must be implemented, unless they are static or final
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class Cat: IAnimal { // Cat inherits from IAnimal interface
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this() { }
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void makeSound() { // implements makeSound function
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import std.stdio: writeln;
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writeln("Meow...");
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}
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}
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//--------------------------//
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class Dog: IAnimal { // Dog inherits from IAnimal interface
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this() { }
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void makeSound() { // implements makeSound function
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import std.stdio: writeln;
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writeln("Woof woof...");
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}
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}
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class Cow: IAnimal { // Cow inherits from IAnimal interface
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this() { }
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void makeSound() { // implements makeSound function
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import std.stdio: writeln;
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writeln("Moooo...");
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}
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}
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