Lesson 40 of 55
9 mins readClass Inheritance & Method Overriding
In Plain English
Inheritance in Lua is accomplished by making a subclass table delegate to its parent class via `setmetatable(Subclass, { __index = Superclass })`.
Deep Dive: How It Works
Subclass Declaration: `Subclass = Superclass:new()` creates a subclass table inheriting from `Superclass`.
Method Overriding: Redefining `function Subclass:method()` overrides the parent version for subclass instances.
Calling Super: Call parent method explicitly with `Superclass.method(self, ...)`.
Core Rules to Remember
Prototype Inheritance Chain: Instance -> Subclass -> Superclass lookup chain.
Method Overriding: Subclasses provide specialized implementations of base methods.
Live Interactive Example
Hit Run Code to see it liveInheritance Hierarchy in Lua
Python 3.12
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Output Console
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How it works: Dog inherited Animal constructor and overrode the speak method.
Your Turn: Micro Challenge
No pressure! Edit the starter code below and test your solution with instant feedback.
Micro Exercise
Override Worker Method
- Create `local Worker = {} Worker.__index = Worker function Worker:new(name) local o = {name=name} setmetatable(o, self) return o end function Worker:work() return self.name .. " is working" end`.
- Create `local Dev = Worker:new() Dev.__index = Dev function Dev:work() return self.name .. " is coding Lua" end`.
- Instantiate `local d = Dev:new("Alice")` and print(d:work()).
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Sandbox Output
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