Heroku-like spinner

spinner.go

package main

import (
	"fmt"
	"time"
)

type spinner struct {
	chars   []string
	current int
}

func (s *spinner) next() string {
	s.current = (s.current + 1) % len(s.chars)
	return s.chars[s.current]
}

func newSpinner() spinner {
	return spinner{
		chars:   []string{"⢿", "⣻", "⣽", "⣾", "⣷", "⣯", "⣟", "⡿"},
		current: 0,
	}
}

func main() {
	s := newSpinner()
	fmt.Print("this gonna take a while...  ")
	for {
		fmt.Printf("\b%s", s.next())
		time.Sleep(100 * time.Millisecond)
	}
}