Applications

• Regular expressions

  Regular expressions are a convenient ways to express patterns (i.e. for search). There are a number of tools which use regular expressions:

  • grep pattern matching program (UNIX)

  • sed stream editor (UNIX)

  • lex A generator for lexical analyzers (UNIX)

• Grammars for programming languages.

  See the appendix of the The Java Language Specification. This is a context free grammar.

  YACC is a tool which can be used to generate a C program (a parser) from a grammar. Parser generators now also exist for other languages, like Java CUP for Java.

• Specifying protocols

  See section 2.1 (pp 38 - 45) contains a simple example of how a protocol for electronic cash can be specified and analyzed using finite automata.