Formal Languages and Computation

Formal Languages and Computation: Models and Their Applications gives a clear, comprehensive introduction to formal language theory and its applications in computer science. It covers all rudimental topics concerning formal languages and their models, especially grammars and automata, and sketches the basic ideas underlying the theory of computation, including computability, decidability, and computational complexity. Emphasizing the relationship between theory and application, the book describes many real-world applications, including computer science engineering techniques for language processing and their implementation. Covers the theory of formal languages and their models, including all essential concepts and properties Explains how language models underlie language processors Pays a special attention to programming language analyzers, such as scanners and parsers, based on four language models-regular expressions, finite automata, context-free grammars, and pushdown automata Discusses the mathematical notion of a Turing machine as a universally accepted formalization of the intuitive notion of a procedure Reviews the general theory of computation, particularly computability and decidability Considers problem-deciding algorithms in terms of their computational complexity measured according to time and space requirements Points out that some problems are decidable in principle, but they are, in fact, intractable problems for absurdly high computational requirements of the algorithms that decide them In short, this book represents a theoretically oriented treatment of formal languages and their models with a focus on their applications. It introduces all formalisms concerning them with enough rigors to make all results quite clear and valid. Every complicated mathematical passage is preceded by its intuitive explanation so that even the most complex parts of the book are easy to grasp. After studying this book, both student and professional should be able to understand the fundamental theory of formal languages and computation, write language processors, and confidently follow most advanced books on the subject.INTRODUCTION Mathematical Background Logic Sets and Sequences Relations Graphs Formal Languages and Rewriting Systems Formal Languages Rewriting systems Synopsis of the Book REGULAR LANGUAGES AND THEIR MODELS Models for Regular Languages Finite Automata Restricted Finite Automata Regular Expressions and their Equivalence with Finite Automata Implementation of Finite Automata Introduction to Lexical Analysis Implementation of a Scanner Properties of Regular Languages Pumping Lemma for Regular Languages Closure Properties CONTEXT-FREE LANGUAGES AND THEIR MODELS Models for Context-Free Languages Context-Free Grammars Restricted Context-Free Grammars Pushdown Automata Applications of Models for Context-Free Languages: Syntax Analysis Introduction to Syntax Analysis Top-Down Parsing Bottom-Up Parsing Properties of Context-Free Languages Pumping Lemma for Context-Free Languages Closure Properties TURING MACHINES AND COMPUTATION Turing Machines and Their Variants Turing Machines and Their Languages Restricted Turing Machines Universal Turing Machines Applications of Turing Machines: Theory of Computation Computability Decidability Turing Machines and General Grammars General Grammars and Their Equivalence with Turing Machines Context-Sensitive Grammars and Linear-Bounded Automata Relations between Language Families CONCLUSION Concluding and Bibliographical Remarks Summary Modern Trends Bibliographical and Historical Remarks