A simple Visual Studio Code extension that automatically counts the number of lines in C functions and inserts a comment above each function with the line count. 😸

👀 Like this:

// »»-----► Number of lines: 1
void square(int *x) {
    *x = (*x) * (*x);
}

Usage 🛸

The extension provides two commands:

✅ Adding line counters:

• 42 Line Counter: Adds line count comments above each function
  • Press Ctrl + Alt + C (Windows/Linux)
  • Press Ctrl+ Cmd + C (Mac)

❌ Removing line counters:

• 42 Line Remove: Removes all previously added line count comments
  • Press Ctrl + Alt + F (Windows/Linux)
  • Press Ctrl + Cmd + F (Mac)

Demo 🎥

---

Supported Languages 🌐

C files (.c)

Features 🛰️

• 📏 Counts lines inside C functions
• 💬 Writes a comment containing the number of lines
• ❌ Excludes the opening { and closing } braces from the count
• 🧹 Remove feature: Clean up all line count comments

⚠️

Note:

• Counts empty lines within functions
• Does not count comment lines

⚠️

---

☄️ Installation

📕From the VS Code Marketplace

• Open Extensions in VS Code
• Search for 42LineCounter
• Click Install

📘 Using a .vsix file

• Download the .vsix file from Github
• In VS Code, press Ctrl + Shift + P (Windows/Linux) or Cmd + Shift + P (Mac)
• Type "Extensions: Install from VSIX..."
• Choose the downloaded .vsix file

---

Project Structure

.
├── 42-line-counter-0.0.2.vsix      # Packaged VS Code extension file (installable)
├── CHANGELOG.md                    # Log of changes and version history
├── eslint.config.mjs               # ESLint configuration for linting code
├── img                             # Images used in README, marketplace, or UI
│   ├── demo.gif                    # Demo animation/GIF showing extension usage
│   ├── logo.png                    # Main logo for the extension
│   └── logo_.png                   # Alternative/variant of the logo
├── out                             # Compiled JavaScript output (from TypeScript)
│   ├── extension.js                # Compiled main extension entry file
│   ├── extension.js.map            # Source map for debugging extension.js
│   ├── formatters                  # Compiled formatter utilities
│   │   ├── functionFormatter.js    # Compiled function formatter logic
│   │   └── functionFormatter.js.map # Source map for functionFormatter.js
│   └── test                        # Compiled test files
│       ├── extension.test.js       # Compiled extension tests
│       └── extension.test.js.map   # Source map for extension.test.js
├── package.json                    # Project metadata & dependencies for VS Code extension
├── package-lock.json               # Exact dependency tree (auto-generated by npm)
├── README.md                       # Documentation and usage instructions
├── src                             # Source TypeScript code (before compilation)
│   ├── extension.ts                # Main entry point for the extension
│   ├── formatters                  # Formatter-related logic (TypeScript source)
│   │   └── functionFormatter.ts    # Function formatting logic in TS
│   └── test                        # Test files (TypeScript source)
│       └── extension.test.ts       # Tests for the extension
├── tsconfig.json                   # TypeScript compiler configuration
└── vsc-extension-quickstart.md     # Auto-generated guide for creating extensions

---

⭐ Configuration and Customization

🚨 After Making Changes

1. Install dependencies: npm install
2. Recompile: npm run compile
3. Package extension: vsce package
4. Install the generated: .vsix file

---

Renaming Commands

If you want to modify the command names that appear in the VSCode command palette, you need to edit the package.json file.

⚙️ File to modify: package.json

Find the contributes.commands section:

{
  "contributes": {
    "commands": [
      {
        "command": "42-line-counter.countLines",
        "title": "42 Line Counter"           ← Modify this title
      },
      {
        "command": "42-line-counter.removeComments", 
        "title": "42 Line Remove"            ← Modify this title
      }
    ]
  }
}

Examples : For shorter names

{
  "commands": [
    {
      "command": "42-line-counter.countLines",
      "title": "Line Count"
    },
    {
      "command": "42-line-counter.removeComments",
      "title": "Remove Count"
    }
  ]
}

🚨 Important note: Only the package.json file should be modified to rename commands.

The TypeScript code in extension.ts uses command identifiers (42-line-counter.countLines and 42-line-counter.removeComments) which should NOT be changed.

---

🖍️ Customizing Comment Prefix

If you want to change the appearance of the comment prefix '// »»-----►', you need to modify the extension.ts file.

File to modify: src/extension.ts

.
├── src
    └── extension.ts  <--- HERE

Find and modify :

const commentPrefix = '// »»-----►';    ← Change this line

And also update :

return trimmed.startsWith('// »»-----►');    ← Change this line too

Examples

const commentPrefix = '// [LINE COUNT]';

return trimmed.startsWith('// [LINE COUNT]');

🚨 Important: Both lines must use the exact same prefix for the remove function to work properly! 🚨

📜 License

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

Changelog 📝

v0.0.1 - Initial release : August 20, 2025

v0.0.2 - Initial release : August 21, 2025