func unusePhonemizer(id string, phonemizers map[string]Phonemizer) bool {
	_, ok := phonemizers[id]
	if ok {
		delete(phonemizers, id)
	}
	return ok
}
unusePhonemizer discards a phonemizer from the given registry.
package hangulize
type Phonemizer interface {
	ID() string
	Phonemize(string) string
}
func usePhonemizer(p Phonemizer, phonemizers map[string]Phonemizer) bool {
	id := p.ID()
	if _, ok := phonemizers[id]; ok {
		return false
	}
	phonemizers[id] = p
	return true
}