Learn Scala by Examples
Scala 3Scala combines object-oriented and functional programming in one high-level language. Static types help avoid bugs in complex applications, and its JVM runtimes let you build high-performance systems with easy access to huge ecosystems of libraries.
These examples cover the core concepts of Scala, from its powerful type system and functional programming features to its concise syntax for object-oriented design.
Variables
Understanding Scala variable declarations with this sample code demonstrating immutable val for functional programming, mutable var for state changes, lazy evaluation for deferred computation, type inference capabilities, and string interpolation syntax.
Functions
Exploring Scala functions as first-class citizens with this code example showing standard function definitions, concise single-expression syntax, higher-order functions accepting function parameters, anonymous lambda expressions, placeholder syntax, and nested helper functions.
Classes
Defining object blueprints with this sample code demonstrating primary constructor parameters in class signature, val for immutable and var for mutable properties, method definitions, auxiliary constructors, and mandatory override keyword for parent method overriding.
Traits
Implementing code reuse through mixin composition with this code example showing trait definitions with concrete and abstract methods, multiple trait mixing using with keyword, trait implementation requirements, and instance-level trait mixing for dynamic behavior modification.
Case Classes
Modeling immutable data structures with this sample code demonstrating case class auto-generated methods, instantiation without new keyword, structural equality comparison, copy method for creating modified instances, built-in toString implementation, and seamless pattern matching support.
Objects
Creating singletons and static-like members with this code example showing object definitions for single instances, companion objects sharing class names, factory methods using apply, private member access between companions, and lazy singleton initialization.
Collections
Working with Scala collections library through this sample code demonstrating immutable List, Map, and Set data structures, functional operations like map filter and reduce, getOrElse for safe access, unique element enforcement, and for-comprehension syntax for transformations.
Pattern Matching
Leveraging powerful pattern matching with this code example showing value matching, type matching, list destructuring with wildcards, case class deconstruction, guard conditions using if clauses, and default catch-all patterns for comprehensive control flow.
Options
Eliminating null pointer exceptions with this code example demonstrating Option type for representing optional values, Some and None variants, pattern matching for safe unwrapping, functional operations like map and getOrElse, and for-comprehension chaining for optional value processing.
Futures
Managing asynchronous computation with this code example showing Future creation for non-blocking operations, ExecutionContext for thread pool management, callback registration with onComplete, Success and Failure handling, and composing multiple futures using for-comprehensions.