Learn D with Real Code Examples

D supports imperative, object-oriented, and functional programming paradigms.

It offers safe systems-level programming with modern abstractions.

Templates, mixins, and compile-time reflection enable advanced metaprogramming.

Strong static typing with type inference

Modules and package system

Function overloading, operator overloading

First-class functions and closures

Compile-time reflection and code generation

Variables, constants, and types

Functions and procedures

Control flow: if, while, for, switch

Structs, classes, and interfaces

Modules, packages, and imports

src/ - D source files

tests/ - unit and integration tests

dub.json - project configuration and dependencies

examples/ - sample programs

docs/ - project documentation

Write source code (.d files)

Compile using dmd, ldc, or gdc

Use Dub for dependencies and builds

Run unit tests with built-in test blocks

Deploy native binaries across platforms

Beginner: basic scripts, control flow, functions

Intermediate: classes, templates, operator overloading

Advanced: compile-time reflection, mixins, ranges

Expert: game engines, high-performance computing, concurrency

Research: DSLs, metaprogramming, compiler extensions

Similar performance to C++

Higher-level features than C/C++

Easier syntax than C++ templates

Smaller ecosystem than Rust or Go

Better compile-time metaprogramming than most mainstream languages

1999 – D initial design by Walter Bright

2001 – D1 language released

2007 – D2 language released with modern features

2010s – Growth of ecosystem and community

2020s – Active development and library expansion

Struct: value-type user-defined type

Class: reference-type user-defined type

Template: generic code construct

Mixin: compile-time code insertion

Range: iterable sequence abstraction