Boba

The fun, functional way to build terminal apps. A Go framework based on The Elm Architecture.

⚠️ This project is a pre-release so the API is subject to change a little. That said, we're using it in production.

Simple example

package main

// A simple program that counts down from 5 and then exits.

import (
	"fmt"
	"log"
	"time"
	"github.com/charmbracelet/boba"
)

type model int

type tickMsg time.Time

func main() {
	p := boba.NewProgram(init, update, view, subscriptions)
	if err := p.Start(); err != nil {
		log.Fatal(err)
	}
}

// Listen for messages and update the model accordingly
func update(msg boba.Msg, mdl boba.Model) (boba.Model, boba.Cmd) {
	m, _ := mdl.(model)

	switch msg.(type) {
	case tickMsg:
        m--
		if m == 0 {
			return m, boba.Quit
		}
	}
	return m, nil
}

// Render to the terminal
func view(mdl boba.Model) string {
	m, _ := mdl.(model)
	return fmt.Sprintf("Hi. This program will exit in %d seconds...\n", m)
}

// Subscribe to events
func subscriptions(_ boba.Model) boba.Subs {
    return boba.Subs{
        "tick": time.Every(time.Second, func(t time.Time) boba.Msg {
            return tickMsg(t)
        },
    }
}

Hungry for more? See the other examples.

Other Resources

• Termenv: advanced ANSI style and color support for your terminal applications. Very useful when rendering your views.
• Reflow: a collection of ANSI-aware text formatting tools. Also useful for view rendering.

Acknowledgments

Heavily inspired by both The Elm Architecture by Evan Czaplicki et al. and go-tea by TJ Holowaychuk.

License

MIT

---

Part of Charm.

Charm热爱开源!