Inheritance

A class inherits from another using the extends keyword.

// Base class
  ╰╴No statement matched
class Animal(var String name)
{
  pub fun say_name()
  {
      print($name)
  }
}

// Child class
class Cat(String name, Int lives)
extends Animal(name) {}

Cat("Michi", 9).say_name()
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The call to the parent constructor is done right there, after the parent class name.

class Dog(String name) 
╰╴No statement matched
extends Animal(name) {}
//            |----|
//  This is the call to the parent constructor
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You must always call super, even if the parent doesn’t define any parameters:

class Parent() {}
╰╴No statement matched

class Child()
extends Parent() {}
thp