string_cmd

A Rust library for building powerful string editing components with support for Emacs and Vi-style keybindings. Perfect for terminal applications that need sophisticated text input handling with more flexibility than readline provides.

string_cmd provides default keybindings for Emacs and Vi modes, or you can forego the default keybindings and implement your own.

Installation

cargo add string_cmd

# If you want to use the crossterm events integration:
cargo add string_cmd --features crossterm

Basic Usage

use string_cmd::StringEditor;

// Create a new empty editor
let mut editor = StringEditor::new();

// Or initialize with existing text
let mut editor = StringEditor::with_string("Hello, world!");

// Get the current text
println!("Current text: {}", editor.get_text());

// Get cursor position
println!("Cursor at: {}", editor.cursor_pos());

See the StringEditor documentation for more details.

Crossterm Integration

The library provides seamless integration with crossterm for terminal applications. Here's a complete example:

use std::time::Duration;
use crossterm::{
    cursor, event::{self, KeyCode},
    terminal::{disable_raw_mode, enable_raw_mode},
    execute, terminal,
};
use string_cmd::{StringEditor, events::event_to_command};

fn main() -> std::io::Result<()> {
    let mut editor = StringEditor::new();
    let mut stdout = std::io::stdout();

    println!("Enter text below:");
    enable_raw_mode()?;

    let input = loop {
        if event::poll(Duration::from_millis(10))? {
            let event = event::read()?;
            if let event::Event::Key(key) = &event {
                let ctrl = key.modifiers.contains(event::KeyModifiers::CONTROL);

                match key.code {
                    KeyCode::Esc => break None,
                    KeyCode::Char('q') if ctrl => break None,
                    KeyCode::Enter => break Some(editor.get_text()),
                    _ => {}
                }
            }

            if let Some(command) = event_to_command(&event) {
                editor.execute(command);
            }
        }

        execute!(
            stdout,
            cursor::MoveToColumn(0),
            terminal::Clear(terminal::ClearType::CurrentLine)
        )?;
        print!("{}", editor.get_text());
        execute!(stdout, cursor::MoveToColumn(editor.cursor_pos() as u16))?;
    };

    disable_raw_mode()?;
    println!("\nFinal input: {:?}", input);

    Ok(())
}

Supported Keybindings (with crossterm feature)

Navigation

• Ctrl+B or Left Arrow: Move cursor left
• Ctrl+F or Right Arrow: Move cursor right
• Ctrl+A or Home: Move to start of line
• Ctrl+E or End: Move to end of line

Editing

• Ctrl+H or Backspace: Delete character before cursor
• Ctrl+D or Delete: Delete character at cursor
• Ctrl+K: Delete from cursor to end of line
• Ctrl+U: Delete from start of line to cursor
• Ctrl+W: Delete word leading to cursor

Usage

use string_cmd::StringEditor;

let mut editor = StringEditor::new();
// how you get the event is up to you;
// most commonly, you'll use `crossterm::event::poll()` and `crossterm::event::read()`
let event = get_crossterm_event(); 

if let Some(command) = event_to_command(&event) {
    editor.execute(command);
}

License

This project is licensed under the MIT License.