# PLY-python--lexer-parser-Cpp

**Repository Path**: aprial1980/PLY-python--lexer-parser-Cpp

## Basic Information

- **Project Name**: PLY-python--lexer-parser-Cpp
- **Description**: No description available
- **Primary Language**: Unknown
- **License**: MIT
- **Default Branch**: main
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2025-04-28
- **Last Updated**: 2025-04-28

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# PLY-python--lexer-parser-Cpp
This project is a simple  parser for C++ language, implemented using PLY (Python Lex-Yacc). It includes a lexer and parser to analyze the syntax of input code, supporting features like conditional statements, loops, variable assignments, and expressions. Provides a foundation for understanding lexical analysis and parsing concepts.

*pip install ply*

*Lexer (ply.lex):*

The lexer defines a set of tokens, which are the building blocks of the programming language. Tokens include numbers, operators, keywords, etc.<br/>
Regular expressions are used to define the patterns for each token, such as numbers, arithmetic operators, parentheses, etc.<br/>
Reserved keywords like 'while,' 'if,' 'else,' etc., are specified in a dictionary called reserved.<br/>
The t_ID function identifies identifiers and checks if they are reserved words.<br/>
The lexer also handles comments and ignores whitespace.<br/>

*Parser (ply.yacc):*

The parser specifies the grammar of the language using a set of production rules.<br/>
Precedence rules are defined for operators like +, -, *, and /.<br/>
Productions are defined for the program, type specifiers, parameters, declarations, statements, expressions, assignments, and error handling.<br/>
The p_program rule starts the parsing process, defining a program as a set of statements.<br/>
The p_type_specifier rule defines the type specifier for variables and functions.<br/>
The p_params rule handles function parameters.<br/>
The p_declaration rule defines variable and function declarations.<br/>
The p_statements rule handles program statements, including both declarations and other statements.<br/>
The p_statement rule defines various types of statements such as if, if-else, while, for, and assignments.<br/>
The p_expression rule defines expressions with different operators and operands.<br/>
The p_assignment rule handles variable assignments.<br/>
The p_error function handles syntax errors.<br/>

*Test and Output:*

The code includes a simple test loop where the user can input lines of code.<br/>
The input code is then parsed using the defined parser.<br/>
If the parsing is successful, the parsed result is printed, and "Accepted!" is displayed. Otherwise, a syntax error message is printed, and "Rejected!" is displayed.