Constructors

Constructors and Factory Constructors

Master Dart's constructor forms, default, named, const, and factory constructors, and learn when each pattern is the right tool for building objects.

Pattern Matching in Haskell

Learn how Haskell lets you destructure values directly in function definitions and case expressions to write clear, exhaustive branching logic.

Constructors in Java

Understand Java constructors — default, parameterized, overloaded, and chained — with syntax rules and worked examples.

Constructors in Python

How __init__ initializes new objects, why it isn't really the constructor, and how default values work.

Constructors in JavaScript

How constructor functions and class constructors initialize new objects, run automatically with `new`, and support default parameters.

Constructors in Kotlin (Primary and Secondary)

Understand how primary and secondary constructors initialize Kotlin objects, including init blocks and constructor delegation.

Constructors and Initialization

Explore how constructors establish an object's initial state, including constructor overloading, chaining with 'this'/'base', field initializers, and object in…

Static Members

Learn how static fields, methods, and classes attach behavior and state to a type itself rather than to individual instances, and when that design choice makes…

What is a Copy Constructor?

A copy constructor is a special constructor that creates a new object as a duplicate of an existing object of the same class, copying its field values into the…

What is RAII (Resource Acquisition Is Initialization)?

RAII is a C++ idiom where a resource (memory, a file handle, a lock) is acquired in an object’s constructor and automatically released in its destructor, so th…

What is an Instance Initializer Block?

An instance initializer block is a plain `{ ... }` block (no `static` keyword) written directly in a Java class body that runs once every time a new object is…

What is a Private Constructor?

A private constructor is a constructor declared with the private access modifier so it can only be invoked from within its own class, preventing external code…

What is a Protected Constructor?

A protected constructor is a constructor accessible only to the class itself, its subclasses, and (in Java) other classes in the same package, so it can be use…