ターミナルUI：BubbleTea（Go）vs Ratatui（Rust）

package main

import (
    "fmt"
    "os"
    tea "github.com/charmbracelet/bubbletea"
)

type model struct {
    choices  []string
    cursor   int
    selected map[int]struct{}
}

func (m model) Init() tea.Cmd { return nil }

func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
    switch msg := msg.(type) {
    case tea.KeyMsg:
        switch msg.String() {
        case "ctrl+c", "q":
            return m, tea.Quit
        case "up", "k":
            if m.cursor > 0 { m.cursor-- }
        case "down", "j":
            if m.cursor < len(m.choices)-1 { m.cursor++ }
        case "enter", " ":
            if _, ok := m.selected[m.cursor]; ok {
                delete(m.selected, m.cursor)
            } else {
                m.selected[m.cursor] = struct{}{}
            }
        }
    }
    return m, nil
}

func (m model) View() string {
    s := "What should we buy?\n\n"
    for i, choice := range m.choices {
        cursor := " "
        if m.cursor == i { cursor = ">" }
        checked := " "
        if _, ok := m.selected[i]; ok { checked = "x" }
        s += fmt.Sprintf("%s [%s] %s\n", cursor, checked, choice)
    }
    return s + "\nPress q to quit.\n"
}

func main() {
    if _, err := tea.NewProgram(model{
        choices:  []string{"Buy carrots", "Buy celery", "Buy kohlrabi"},
        selected: make(map[int]struct{}),
    }).Run(); err != nil {
        fmt.Printf("error: %v", err)
        os.Exit(1)
    }
}

use crossterm::event::{self, Event, KeyCode};
use ratatui::{prelude::*, widgets::Paragraph};
use std::time::Duration;

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let mut terminal = ratatui::init();
    loop {
        terminal.draw(|frame| {
            let area = frame.area();
            frame.render_widget(
                Paragraph::new("Hello, Ratatui! Press q to quit.").alignment(Alignment::Center),
                area,
            );
        })?;
        if event::poll(Duration::from_millis(250))? {
            if let Event::Key(key) = event::read()? {
                if key.code == KeyCode::Char('q') {
                    break;
                }
            }
        }
    }
    ratatui::restore();
    Ok(())
}