Lexical Analyzer

Lexical analyzer in C language

Table of Contents

• Overview
• Features
• Getting Started
  • Prerequisites
  • Installation
• Usage
• Example
  • Example Input
  • Example Output
• State mahcine diagram
• Files in the Repository
• License
• Contributing
• Acknowledgments
• Contact

Overview

This project is a Lexical Analyzer (Lexer) using state machine implemented in JavaScript, designed to analyze C language code. It identifies and categorizes tokens from the input code, such as keywords, operators, literals, comments, preprocessors, pointers and delimiters. The output is displayed in a structured format, making it easy to understand the components of the code.

Features

• Token Recognition: Identifies various tokens including keywords, operators, literals, comments, preprocessors, pointers and delimiters.
• Scope Tracking: Maintains scope information for variables and functions.
• State Machine: Implemented with designed state machine.
• Error Handling: Detects and reports invalid tokens.
• User -Friendly Interface: A simple web interface for inputting C code and viewing results.

Getting Started

Prerequisites

• A modern web browser (Chrome, Firefox, etc.)
• Basic understanding of C programming language

Installation

1. Clone the repository:

   git clone https://github.com/Amizaa/Lexical-Analyzer.git
   cd code
   

Usage

1. In the text area provided, write or paste your C code.

2. Click the "Analyse the code" button.

3. The output will be displayed in a table format below the input area, showing the tokens identified along with their types, column numbers, line numbers, and scope.

Example

Input

You can use the following sample C code to test the analyzer:

#include <stdio.h>

int main() {
    int a = 5;
    float b = 2.5;
    if (a > b) {
        printf("a is greater than b");
    }
    return 0;
}

Output

Token	Type	Column	Line	Scope
#include	Preprocessor	1	1	global
<stdio.h>	Header File	10	1	global
int	Keyword	1	3	global
main	Identifier	5	3	global
(	Bracket	9	3	global
)	Bracket	10	3	global
{	Bracket	12	3	1
int	Keyword	5	4	1
a	Identifier	9	4	1
=	Assignment Operator	11	4	1
5	Integer Literal	13	4	1
;	Delimiter	14	4	1
float	Keyword	5	5	1
b	Identifier	11	5	1
=	Assignment Operator	13	5	1
2.5	Real Number Token	15	5	1
;	Delimiter	18	5	1
if	Keyword	5	6	1
(	Bracket	8	6	1
a	Identifier	9	6	1
>	Comparison Operator	11	6	1
b	Identifier	13	6	1
)	Bracket	14	6	1
{	Bracket	16	6	2
printf	Identifier	9	7	2
(	Bracket	15	7	2
"a is greater than b"	String Literal	16	7	2
)	Bracket	37	7	2
;	Delimiter	38	7	2
}	Bracket	5	8	1
return	Keyword	5	9	1
0	Integer Literal	12	9	1
;	Delimiter	13	9	1
}	Bracket	1	10	global

For test and see more example, you can use the test-code1.txt and test-code2.txt files.

State Machine Diagram

Files in the Repository

• LICENSE: Contains the MIT License for the project.
• README.md: This documentation file.
• code/Lexical_Analyser.js: The main JavaScript file that implements the lexical analysis logic.
• code/bootstrap.min.css: The Bootstrap CSS file for styling the web interface.
• code/index.html: The HTML file that provides the user interface for the lexical analyzer.
• test-code1.txt: A sample C code file for testing the analyzer.
• test-code2.txt: Another sample C code file for testing the analyzer.
• lexer-state-machine.png: lexer state machine diagram.

License

This project is licensed under the MIT License. See the LICENSE file for details.

Contributing

Contributions are welcome! Please feel free to submit a pull request or open an issue for any suggestions or improvements.

Acknowledgments

This project was inspired by the need for a better understanding of lexical analysis in programming languages. Special thanks to the creators of Bootstrap for the UI framework used in this project.

Contact

For any inquiries or feedback, please reach out to:

• Your Name - Amirreza Noruzi
• GitHub: Amizaa