merkle/simple_map.go
func (sm *simpleMap) Set(key string, value Hasher) {
	sm.sorted = false

	// The value is hashed, so you can
	// check for equality with a cached value (say)
	// and make a determination to fetch or not.
	vhash := value.Hash()

	sm.kvs = append(sm.kvs, cmn.KVPair{
		Key:   []byte(key),
		Value: vhash,
	})
}
func (sm *simpleMap) Set(key string, value Hasher) {
	sm.sorted = false

	// The value is hashed, so you can
	// check for equality with a cached value (say)
	// and make a determination to fetch or not.
	vhash := value.Hash()

	sm.kvs = append(sm.kvs, cmn.KVPair{
		Key:   []byte(key),
		Value: vhash,
	})
}
// Set hashes the key and value and appends it to the kv pairs.