Code Reuse

What is Inheritance in OOP?

Inheritance is the object-oriented mechanism by which a class (the subclass) acquires the fields and methods of another class (the superclass), enabling code r…

What is the Template Method Pattern?

The Template Method pattern is a behavioral design pattern where a base class defines the fixed skeleton of an algorithm in a single method, deferring specific…

What are Mixins in Object-Oriented Programming?

A mixin is a class designed to bundle a specific, reusable piece of behavior that is "mixed into" other classes, typically via multiple inheritance or composit…

What are Traits in Object-Oriented Programming?

A trait is a reusable, stateless unit of method implementations that can be composed into a class, similar in spirit to a mixin but with an explicit conflict-r…

Mixins vs Traits vs Interfaces: What is the Difference?

Interfaces declare a contract of method signatures with no implementation (in their classic form), mixins bundle reusable method implementations composed via i…

What is Delegation in OOP?

Delegation is an object-oriented technique where an object, instead of implementing a behavior itself, hands the request off to a second helper object that act…

What Does super Do in OOP?

"super" is a keyword used inside a subclass to call a method or constructor defined on its parent class, most commonly to invoke the parent constructor or to e…

What is a Trait Conflict?

A trait conflict occurs when a class composes two or more traits (or mixins) that each define a method with the same name and signature, leaving the compiler o…

What is an Extension Method?

An extension method is a language feature that lets you add a new method to an existing type from outside its definition, without modifying the type’s source c…

How Do You Design a Good Custom React Hook?

A well-designed custom hook extracts reusable stateful logic — not UI — behind a function starting with “use”, returning a small, purposeful API (values and fu…

What Are Higher-Order Components (HOCs) in React?

A higher-order component is a function that takes a component as an argument and returns a new component with added behavior or props, letting you reuse cross-…

What Is the Render Props Pattern in React?

The render props pattern is a technique where a component accepts a function as a prop — often literally named `render`, or passed as `children` — and calls th…

What Are TypeScript Utility Types Like Partial and Pick?

Utility types are built-in generic type transformations, such as Partial, Pick, Omit, and Readonly, that derive a new type from an existing one instead of forc…