Compiler Project: Lex and Yacc

This project involves building a compiler using Lex and Yacc. The instructions below will guide you on how to set up, run, and use a graphical user interface (GUI) with the compiler.

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How to Run Lex and Yacc in Visual Studio Code

Step 1: Install Flex and Bison

• Download and install Flex and Bison from WinFlexBison or you can download the .exe file from Program/Program.zip file.

Step 2: Update Environment Variables

1. Open the Start menu and search for "Environment Variables."
2. Click on Environment Variables.
3. Edit the Path variable by adding:
   • The path to flex.
   • The path to gcc.

Step 3: Create Files

1. Create a new folder.
2. Add the following files to the folder:
   • LexFile.l
   • YaccFile.y

Step 4: Install VS Code Extensions

Install the following extensions in Visual Studio Code:

• Flex Extension
• Lex Extension
• Bison Extension

How Run Lex Only ?

Run the following command in the terminal:

flex LexFile.l; gcc lex.yy.c -o Lex; ./Lex.exe

How Run Lex and Yacc ?

Run the following commands in the terminal:

flex LexFile.l; yacc -d YaccFile.y; gcc lex.yy.c -o lexer; gcc YaccFile.tab.c lex.yy.c -o program

Step 5: Run in Visual Studio Code

1. Open the terminal in VS Code.
2. Execute:

   flex LexFile.l; yacc -d YaccFile.y; gcc lex.yy.c -o lexer; gcc YaccFile.tab.c lex.yy.c -o program

3. Run the compiled program:

   ./program.exe

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How to Use GUI with Lex and Yacc

This section explains how to create and use a GUI with the compiler, leveraging the customtkinter Python library.

Step 1: Install Python

Download and install Python from python.org.

Step 2: Install Required Libraries

Install customtkinter (or tkinter) by running:

pip install customtkinter

Step 3: Create GUI File

1. Create a new file named GUI.py.
2. Import the required libraries:

   import tkinter as tk
   import customtkinter as ctk
   import subprocess
   import os

Step 4: Create a Function to Run Lex and Yacc

Define a function use_GUI() to run the program and display the output:

def use_GUI():
    user_input = text_input.get("1.0", tk.END).strip()  
    process = subprocess.Popen(["program.exe"], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    stdout, stderr = process.communicate(input=user_input.encode())  
    result_output.delete("1.0", tk.END)  
    result_output.insert(tk.END, stdout.decode())  

• Ensure the path to program.exe is correct.
• This function captures user input, executes the program, and displays the output in the GUI.

Step 5: Create the GUI Layout

Design the GUI:

root = ctk.CTk()  
root.title("Compiler")
root.geometry("1400x800")  

root.grid_rowconfigure(0, weight=1, minsize=5)  
root.grid_rowconfigure(1, weight=0, minsize=5)
root.grid_columnconfigure(0, weight=1, minsize=5)
root.grid_columnconfigure(1, weight=0, minsize=5)  
root.grid_columnconfigure(2, weight=1, minsize=5)

text_input = ctk.CTkTextbox(root, height=10, width=30, font=("Consolas", 19, "bold"), wrap=tk.WORD, corner_radius=8)
text_input.grid(row=0, column=0, padx=20, pady=10, sticky="nsew")

result_output = ctk.CTkTextbox(root, height=10, width=30, font=("Consolas", 19, "bold"), wrap=tk.WORD, corner_radius=8)
result_output.grid(row=0, column=1, columnspan=3, padx=10, pady=10, sticky="nsew")

run_button = ctk.CTkButton(root, text="Run Code", command=use_GUI, width=200, height=40, font=("Consolas", 15, "bold"))
run_button.grid(row=2, column=0, padx=20, pady=10)

root.mainloop()

Step 6: Run the GUI

Run GUI.py to start the graphical interface.

Notes

• Ensure program.exe is in the same folder as GUI.py.
• After updating the Lex or Yacc files, rebuild the program using:

  flex LexFile.l; yacc -d YaccFile.y; gcc lex.yy.c -o lexer; gcc YaccFile.tab.c lex.yy.c -o program

Light Mode

Dark Mode

Youtube Videos

• How to install in VS-Code
• Arabic Flex Tutorial

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This README file provides a comprehensive guide to setting up, running, and enhancing your compiler project with a GUI. Make sure to follow each step carefully for a successful implementation.