Essentials of Programming Languages

What really happens when a program runs? "Essentials of Programming Languages" teaches the fundamental concepts of programming languages through numerous short programs, or "interpreters" that actually implement the features of a language. Nearly 300 exercises using these programs provide a hands-on undertanding of programming principles that is hard, if not impossible, to achieve by formal study alone. In an approach that is uniquely suited to mastering a new level of programming structure, the authors derive a sequence of interpreters that begins with a high-level operational specification (close to formal semantics) and ends with what is effectively assembly language - a process involving programming transformation techniques that should be in the toolbox of every programmer. The first four chapters provide that foundation for an in-depth study of programming languages, including most of the features of Scheme, needed to run the language-processing programs of the book. The next four chapters form the core of the book, deriving a sequence of interpreters ranging from very high- to very low-level. The authors then explore variations in programming language semantics, including various parameter-passing techniques for transforming interpreters that ultimately allow the interpreter to be implemented in any low-level language. They conclude by discussing scanners and parsers and the derivation of a compiler and virtual machine from an interpreter.