Module 2: Lexical Analysis

No. of lectures : 5

Topics Covered

1. Motivation
2. Basic Concepts and Issues
3. Handcoding a Lexical Analyser
4. Automatic generation of Lexical Analysers
5. Minimization of DFA
6. Efficient representation of DFA.

Objectives At the conclusion of the module, the student should be able to :

1. Understand the role of lexical analysis and the interface of a lexical analyser with the rest of the compiler.
2. Identify tokens in a language and the action to performed on discovery of a token.
3. Understand the issues involved in handcoding a lexical analyser.
4. Express tokens in a language through regular expressions and be able to specify action routines along with token specifications.
5. See a DFA as a recogniser of tokens. Understand the algorithms involved in converting regular expressions into a minimized DFA.
6. See clearly that the DFA, a driver routine and the action routines, combined appropriately, indeed constitute a lexical analyser.
7. Understand the need for an efficient representation of a DFA and see how it can be achieved by a particular representation using four arrays.