package metadata

// M is a string key-value metadata map used throughout IOP.
type M map[string]string

func (m M) Get(key string) string {
	if m == nil {
		return ""
	}
	return m[key]
}

func (m M) Set(key, value string) M {
	if m == nil {
		m = make(M)
	}
	m[key] = value
	return m
}

func (m M) Merge(other M) M {
	out := make(M, len(m)+len(other))
	for k, v := range m {
		out[k] = v
	}
	for k, v := range other {
		out[k] = v
	}
	return out
}