Dotty is the project name for technologies that are considered for inclusion in Scala 3. Scala has pioneered the fusion of object-oriented and functional programming in a typed setting. Scala 3 will be a big step towards realizing the full potential of these ideas. Its main objectives are to

• become more opinionated by promoting programming idioms we found to work well,
• simplify where possible,
• eliminate inconsistencies and surprising behaviors,
• build on strong foundations to ensure the design hangs well together,
• consolidate language constructs to improve the language’s consistency, safety, ergonomics, and performance.

In this documentation you will find information on how to use the Dotty compiler on your machine, navigate through the code, setup Dotty with your favorite IDE and more!

Table of Contents

• Blog

• Usage

  • Getting Started

  • sbt-projects

  • IDE support for Dotty

  • Worksheet mode in Dotty IDE

  • cbt-projects

  • Dottydoc

• Reference

  • Overview

  • New Types

    • Intersection types

    • Union types

    • Type lambdas

    • Match types

    • Dependent Function Types

  • Enums

    • Enumerations

    • Algebraic Data Types

    • Translation

  • Contextual Abstractions

    • Overview

    • Given Instances

    • Using Clauses

    • Context Bounds

    • Given Imports

    • Extension Methods

    • Implementing Typeclasses

    • Typeclass Derivation

    • Multiversal Equality

    • Context Functions

    • Implicit Conversions

    • By-Name Context Parameters

    • Relationship with Scala 2 Implicits

  • Metaprogramming

    • Overview

    • Inline

    • Macros

    • Staging

    • TASTy Reflection

    • TASTy Inspection

  • Other New Features

    • Trait Parameters

    • Creator Applications

    • Export Clauses

    • Opaque Type Aliases

    • Open Classes

    • Parameter Untupling

    • Kind Polymorphism

    • Tupled Function

    • threadUnsafe Annotation

    • New Control Syntax

    • Optional Braces

    • Explicit Nulls

    • Safe Initialization

  • Other Changed Features

    • Numeric Literals

    • Structural Types

    • Operators

    • Wildcard Types

    • Type Checking

    • Type Inference

    • Implicit Resolution

    • Implicit Conversions

    • Overload Resolution

    • Match Expressions

    • Vararg Patterns

    • Pattern Bindings

    • Pattern Matching

    • Eta Expansion

    • Compiler Plugins

    • Lazy Vals initialization

    • Main Functions

  • Dropped Features

    • DelayedInit

    • Macros

    • Existential Types

    • Type Projection

    • Do-While

    • Procedure Syntax

    • Package Objects

    • Early Initializers

    • Class Shadowing

    • Limit 22

    • XML literals

    • Symbol Literals

    • Auto-Application

    • Weak Conformance

    • Nonlocal Returns

    • [this] Qualifier

• Contributing

  • Contribute Knowledge

  • Getting Started

  • Workflow

  • Testing

  • Debugging

  • IDEs and Tools

    • Mill

    • Scalafix

  • Procedures

    • Release Model

    • Modifying the Test Framework

• Internals

  • Backend

  • Classpaths

  • Core Data Structrues

  • Contexts

  • Dotc vs Scalac

  • Higher-Kinded Types

  • Overall Structure

  • Periods

  • Syntax

  • Type System

  • Dotty Internals 1: Trees & Symbols (Meeting Notes)

  • Debug Macros

• Resources

  • Talks