Compiler Design /Construction | Module 2: Lexical Analysis by Prakhar Chauhan | Learn Smarter
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Module 2: Lexical Analysis

Lexical Analysis is an essential phase of the compiler that transforms raw source code into structured tokens required for parsing. It involves the identification of tokens through a meticulous scanning of the input stream, employing techniques like regular expressions and deterministic finite automata for pattern recognition. This chapter explains the roles, responsibilities, and mechanisms involved in lexical analysis while also introducing tools such as LEX and Flex which automate the lexer generation process.

Sections

  • 2

    Lexical Analysis

    Lexical analysis is the initial phase of a compiler that converts unstructured source code into meaningful tokens, streamlining the parsing process.

    Learning Practice

  • 2.1

    The Role Of Lexical Analysis: Breaking Down The Raw Input

    Lexical analysis is the first phase of a compiler that transforms raw source code into meaningful tokens.

    Learning Practice

  • 2.2

    Token, Lexemes, And Token Codes: The Building Blocks

    This section introduces key concepts in lexical analysis, specifically focusing on tokens, lexemes, and token codes, which form the basis of how source code is interpreted by compilers.

    Learning Practice

  • 2.3

    Regular Expressions (Re) To Represent Tokens: Defining The Patterns

    This section discusses how regular expressions are used to define token patterns in lexical analysis, highlighting their role in simplifying the recognition of tokens.

    Learning Practice

  • 2.4

    Deterministic Finite Automata (Dfa): The Engine For Recognition

    Deterministic Finite Automata (DFA) are computational models that recognize patterns defined by regular expressions, serving as the engine behind lexical analyzers.

    Learning Practice

  • 2.5

    Traversing A Dfa For Recognizing Tokens: The Scanner's Algorithm

    This section explains how the scanner algorithm traverses a Deterministic Finite Automaton (DFA) to recognize tokens in the input stream by applying the longest match principle.

    Learning Practice

  • 2.6

    Generating A Lexical Analyzer Using Lex/flex: Automation And Practicality

    This section outlines how LEX and Flex simplify the creation of lexical analyzers through automation and optimization.

    Learning Practice

References

Untitled document (27).pdf

Class Notes

Memorization

What we have learnt

  • Lexical analysis serves as ...
  • Regular expressions and fin...
  • Tools like LEX and Flex str...

Final Test

Revision Tests