Program Transformation: Language Design with the Visitor Pattern

Understanding how compilers and interpreters process code is one of the most powerful skills a developer can acquire. By breaking down source code into structured trees, you can analyze, modify, and translate programming languages from the inside out. In this text-only course, you will master the fundamentals of program transformation using the Visitor Pattern. You will progress from understanding core compiler terminology to manipulating Abstract Syntax Trees (ASTs) and implementing clean, maintainable code transformation pipelines. What you'll learn: Understand the foundational phases of compilers and interpreters, including parsing and code generation; Analyze Abstract Syntax Trees (ASTs) to map out code structure and relationships; Implement the Visitor Pattern to separate data structures from the algorithms operating on them; Perform program transformations to optimize, refactor, or translate source code; Apply modern type-safe design patterns to ensure robust tree traversal; Design a basic custom language pipeline that reads and transforms code steps. The course begins with essential compiler concepts and AST definitions before moving into step-by-step written explanations. You will read clear code examples demonstrating how to traverse and modify structured syntax trees to implement real-world transformations. This course is designed for curious developers and aspiring language creators who want to understand compilers from scratch, with no advanced mathematical background required. Start reading today to unlock the inner workings of programming languages and build your first code transformer.