Written by the creator of the Unicon programming language, this book will show you how to implement programming languages to reduce the time and cost of creating applications for new or specialized areas of computing

• Reduce development time and solve pain points in your application domain by building a custom programming language
• Learn how to create parsers, code generators, file readers, analyzers, and interpreters
• Create an alternative to frameworks and libraries to solve domain-specific problems

The need for different types of computer languages is growing rapidly and developers prefer creating domain-specific languages for solving specific application domain problems. Building your own programming language has its advantages. It can be your antidote to the ever-increasing size and complexity of software.

In this book, you'll start with implementing the frontend of a compiler for your language, including a lexical analyzer and parser. The book covers a series of traversals of syntax trees, culminating with code generation for a bytecode virtual machine. Moving ahead, you'll learn how domain-specific language features are often best represented by operators and functions that are built into the language, rather than library functions. We'll conclude with how to implement garbage collection, including reference counting and mark-and-sweep garbage collection. Throughout the book, Dr. Jeffery weaves in his experience of building the Unicon programming language to give better context to the concepts where relevant examples are provided in both Unicon and Java so that you can follow the code of your choice of either a very high-level language with advanced features, or a mainstream language.

By the end of this book, you'll be able to build and deploy your own domain-specific languages, capable of compiling and running programs.

• Perform requirements analysis for the new language and design language syntax and semantics
• Write lexical and context-free grammar rules for common expressions and control structures
• Develop a scanner that reads source code and generate a parser that checks syntax
• Build key data structures in a compiler and use your compiler to build a syntax-coloring code editor
• Implement a bytecode interpreter and run bytecode generated by your compiler
• Write tree traversals that insert information into the syntax tree
• Implement garbage collection in your language

This book is for software developers interested in the idea of inventing their own language or developing a domain-specific language. Computer science students taking compiler construction courses will also find this book highly useful as a practical guide to language implementation to supplement more theoretical textbooks. Intermediate-level knowledge and experience working with a high-level language such as Java or the C++ language are expected to help you get the most out of this book.

1. Why Build Another Programming Language
2. Programming Language Design
3. Scanning Source Code
4. Parsing
5. Syntax Trees
6. Symbol Tables
7. Checking Base Types
8. Checking Types on Arrays, Method Calls, and Structure Accesses
9. Intermediate Code Generation
10. Syntax Cloning in an IDE
11. Bytecode Interpreters
12. Generating Bytecode
13. Native Code Generation
14. Implementing Operators and Built-In Functions
15. Domain Control Structures
16. Garbage Collection
17. Final Thoughts
18. Appendix A - Unicon Essentials