Explore why you might build a new programming language, which aspects influence runtime and language design choices, and how to implement a working first-version interpreter for that language in C++.

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Key Features

• Design a domain-specific language to solve focused problems and reduce complexity and bugs
• Follow a bottom-up approach, from runtime design to interpreter implementation
• Build an interpreter from scratch as a functional, minimum viable product

Book Description

Designing a custom programming language can be the most effective way to solve certain types of problems—especially when precision, safety, or domain-specific expressiveness matters. This book guides you through the full process of designing and implementing your own programming language and interpreter, from language design to execution, using modern C++.

You’ll start by exploring when and why building a domain-specific language is worth it, and how to design one to fit a specific problem domain. Along the way, you’ll examine real-world interpreter architectures and see how their design decisions affect language behavior, capabilities, and runtime trade-offs.

The book then walks through the entire process of interpreter implementation: defining syntax, building a lexer and parser, designing an abstract syntax tree, generating executable instructions, and implementing a runtime. All examples are in modern C++, with a focus on clean architecture and real-world usability.

By the end, you’ll have a fully working interpreter for a domain-specific language designed to handle network protocols—plus the knowledge and tools to design your own programming language from scratch.

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What you will learn

• Design a domain-specific language and interpreter from scratch
• Write an interpreter that can be embedded into existing environments
• Understand how runtime shapes language execution and interpreter design
• Reason about language design and runtime trade-offs
• Define and implement the execution model of an interpreted language
• Implement a lexer, parser, analyzer, and instruction emitter in C++

Who this book is for

This book is tailored for intermediate to advanced software developers, particularly those interested in language design and implementation. It’s ideal for programmers seeking to expand their skill set and tackle complex problems efficiently. Professionals working in roles such as software engineers, language designers, or system architects will benefit from the practical insights and hands-on experience provided in the book. Good understanding of C++ programming and basic understanding of language design concepts are recommended to fully grasp the content.

Table of Contents

1. Defining the Scope
2. The Blurred Lines Between Native Code, Virtual Machines, and Interpreters
3. Instructions, Concurrency, Inputs, and Outputs
4. Native Types, User Types, and Extension Points
5. Putting It All Together: Making Trade-Off Decisions
6. Review of Programming Language Paradigms
7. Values, Containers, and the Language Meta-model
8. Lexical Scopes
9. Putting It All Together and Creating a Coherent Vision
10. Initialization and Entry Point
11. Execution Frames, the Stack, and Continuations
12. Running and Testing Language Operators
13. Lexing: Turning Text into a Stream of Tokens
14. Parsing: Turning a Stream of Tokens into a Parse Tree

(N.B. Please use the Read Sample option to see further chapters)