func (s *service) AddSampleBeers() {
	for _, b := range beers.DefaultBeers {
		_ = s.bR.Add(b)  
	}
}
AddSampleBeers adds some sample beers to the database
package adding
import (
	"github.com/katzien/go-structure-examples/domain/beers"
)
type Service interface {
	AddBeer(...beers.Beer)
	AddSampleBeers()
}
type service struct {
	bR beers.Repository
}
func NewService(bR beers.Repository) Service {
	return &service{bR}
}
func (s *service) AddBeer(b ...beers.Beer) {
	for _, beer := range b {
		_ = s.bR.Add(beer)  
	}
}