PyLine is a minimalist command-line text editor designed for Linux/BSD systems, written in Python 3 with use of systems calls. Originally created in 2018 and modernized after long pause in 2025, it combines improved text management with a simple, line-by-line workflow. (Note: This is a hobby project, not a professional application.)

• Theme System:
  • Customizable color schemes with only coloring syntax and listing, adjustable for dark and light themes
  • basic text and bacground still from terminal theme (for now)
  • Inhouse solution for editing themes in theme manager
• Configuration Management:
  • Persistent settings with JSON-based configuration
  • Run time config modifying and checking
• Lightweight & Fast: Runs entirely in terminal with minimal dependencies
• Advanced Hook System:
  • Extensible plugin architecture with support for multiple languages (Python, JavaScript, Perl, Ruby, Lua, PHP, Shell)
  • Fully interconnected Hook manager with Config manager
  • Incudes core hook utils for search and replace, smart tab, shell syntax highligting and more
• File Operations:
  • Edit existing files with full hook integration
  • Create new files with directory structure creation
  • Truncate existing files
  • Count words, lines and characters with hookable word counting
• Navigation:
  • Move between lines and scroll file with arrow keys
  • Scroll file by keys PageUp and PageDown
  • Jump to specified line number by J
  • Jump to end of file (Ctrl+D for EOF)
  • Smart viewport management
  • Stylized helpscreen
  • Search and replace functionality provided by core util hook
• Editing:
  • Line-by-line editing with hook-integrated input handling
  • Preserves existing text when modifying lines
  • Insert/delete line operations with pre/post hooks
  • Comprehensive Undo/Redo system (history limit set to 120)
  • Multi-line text selection with visual indicators
  • Cross-platform clipboard support (X11, Wayland, macOS, Windows)
  • Smart indentation preservation during paste operations
  • Syntax highlighting for Python with advanced token recognition
  • Aditional syntax highlighting for shells and JSON via core hooks
• File Browser:
  • Colorized directory listings
  • Change working directories with path persistence
  • Make new directories
  • Remove files and directories
  • Rename files and directories
• Hook Management:
  • Visual hook manager interface (hm command)
  • Priority-based hook execution (90 → 10)
  • Runtime enable/disable without restart
  • Support for multiple scripting languages
  • Hook categories: input handlers, event handlers, syntax handlers, editing operations, clipboard operations, session handlers

Complete screenshot example galery in screenshot-gallery

PyLine after the initialization:

Open file option screen:

Example of line selection:

After pasting the selection from clipboard:

Editing text:

Execmode(Filemanager):

Hook manager:

1st method: Manual run

git clone https://github.com/Peter-L-SVK/PyLine.git
cd PyLine/src/
chmod +x main.py
#Run pwd and copy result path
pwd
#add to your shell config file to run from everywhere
alias pyline='<result of pwd>/main.py'
#run separate install-all.sh in hooks directory
../hooks/install-all.sh
#copy themes to editor's config directory
cp -r $(pwd)/../themes ~/.pyline/
#restart terminal

2nd method (script will run sudo command):

git clone https://github.com/Peter-L-SVK/PyLine.git
cd PyLine/
./install.sh

PyLine stores configuration in ~/.pyline/config.json with the following structure:

{
    "paths": {
		"source_path": "/home/<path-to-pyline>/PyLine/src"
        "original_path": "<current_path_in_terminal>"
		"default_path": "/home/<username>",
    },
    "editor": {
        "theme": "black-on-white"
    },
    "hooks": {
        "enabled": true,
        "auto_reload": false
    },
    "theme": {
        "current": "black-on-white",
        "available_themes": [
            "black-on-white",
            "white-on-black"
        ]
    }
}

~/.pyline/
├── config.json          # Main JSON configuration
├── themes/              # Color theme definitions
└── hooks/               # Extension hook system

In case of manual run:

./main.py

If you used install script:

pyline  #works from anywhere

Editor accpets input arguments:

# Edit existing file
./main.py existing_file.txt # pyline existing_file.txt

# Create new file
./main.py new_file.txt  # pyline new_file.txt

The editor will:

1. For existing files:

   • Load the file
   • Enter edit mode immediately

2. For new files:

   • Create new buffer with specified filename
   • Create new directory in file path if doesn't exist already
   • Enter edit mode

3. With no arguments:

   • Show the original interactive menu

4. -i, --info Show program information and exit

5. -h, --help show help message and exit

To unninstall the program:

./install.sh -u

Advanced Hook System

More about hooks in: hooks-creation and hooks-overview
Manual on how to perform various types of search and replace within core hook in serach-replace manual

Manual on AI asisted grammar hook in AI-grammar-check
For it's proper usage and functionality, install:

pip install language-tool-python numpy pandas

PyLine features a comprehensive hook system that allows extending functionality through plugins. The hook system supports multiple programming languages and follows a structured directory hierarchy:

~/.pyline/hooks/
├── input_handlers/           # Input processing hooks
│   └── edit_line/           # Line editing handlers
│       ├── smart_tab__90.py  # Priority 90 (high)
│       └── auto_complete.py
├── event_handlers/           # Event-based hooks  
│   ├── pre_save/            # Before saving
│   ├── post_save/           # After saving
│   ├── pre_load/            # Before loading
│   ├── post_load/           # After loading
│   └── on_error/            # Error handling
├── syntax_handlers/         # Syntax processing
│   ├── highlight/           # Syntax highlighting
│   └── lint/               # Code linting
├── editing_ops/            # Editing operations
│   ├── pre_insert/         # Before line insertion
│   ├── post_insert/        # After line insertion  
│   ├── pre_delete/         # Before line deletion
│   └── post_delete/        # After line deletion
├── clipboard_ops/          # Clipboard operations
│   ├── pre_copy/           # Before copying
│   ├── post_copy/          # After copying
│   ├── pre_paste/          # Before pasting
│   └── post_paste/         # After pasting
└── session_handlers/       # Session management
    ├── pre_edit/          # Before editing session
    └── post_edit/         # After editing session

• black-on-white: Classic black text on white background
• white-on-black: White text on black background (dark mode)

Create custom themes in ~/.pyline/themes/:

More about themes in: themes-reference

# Create a new theme based on existing one
pyline
# Then type 'tm' for theme manager
# Then 'create my-theme' to create a new theme

Theme file structure (~/.pyline/themes/my-theme.json):

{
  "name": "My Custom Theme",
  "description": "A custom color scheme",
  "background": "\\033[48;5;COLORm",
  "setterm_background": "color-name",
  "setterm_foreground": "color-name",
  "colors": {
    "reset": "\\033[0m",
    "menu_title": "\\033[1;30m",
    "menu_item": "\\033[34m",
    "line_numbers": "\\033[90m",
    "selection": "\\033[47m\\033[30m",
    "keyword": "\\033[34m",
    "string": "\\033[31m",
    "comment": "\\033[32m",
    "variable": "\\033[33m",
    "number": "\\033[35m",
    "function": "\\033[36m",
    "class": "\\033[1;35m",
    "error": "\\033[1;31m",
    "module": "\\033[1;34m",
    "decorator": "\\033[1;36m",
    "annotation": "\\033[1;33m",
    "directory": "\\033[1;34m",
    "executable": "\\033[1;32m",
    "symlink": "\\033[1;36m",
    "hook_category": "\\033[1;35m",
    "hook_type": "\\033[1;36m",
    "hook_enabled": "\\033[1;32m",
    "hook_disabled": "\\033[1;31m"
  }
}

• Hook Language Support:
  • Python: Built-in
  • JavaScript: node runtime
  • Perl: perl interpreter
  • Ruby: ruby interpreter
  • Lua: lua interpreter
  • PHP: php interpreter
  • Shell: bash or zsh interpreter
• Python 3.6+
• Linux(or WSL)/FreeBSD/MacOS system (tested on Fedora 27 MATE, 40/42 Cinnmanon)
• Bash or Zsh shell
• Clipboard: xclip (X11) or wl-clipboard (Wayland) for copy/paste (Comes with GUI/DE)

• Forground Colors: Only partialy applied for now, when editor colors the syntax of when listing.
• Background Colors: For now not implemeted but counted for in themes and code.

GNU GPL v3 - See LICENSE file for details.

To run all tests:

cd PyLine/tests/
./run_tests.py # preferred

# or

python -m unittest discover # traditional

Or run a specific test file:

python -m unittest test_dirops.py

All tests require only Python’s built-in unittest module.

Contributions are welcome!
See CONTRIBUTING file for details.

For contact please see my email in profile info or use GitHub’s built-in communication tools.

Please open an issue or pull request for any:

• Bug fixes

• Feature suggestions

• Documentation improvements

Created by Peter Leukanič in 2018 - A simple editor for when you need to edit text files quickly without leaving the terminal.