diff -ur v3/ezyaml.py v4/ezyaml.py
--- v3/ezyaml.py	2018-08-31 01:39:44.000000000 +0900
+++ v4/ezyaml.py	2018-08-31 02:40:11.000000000 +0900
@@ -90,8 +90,7 @@
 	k = get_value( k.strip() )
 	v = get_value( v.strip() )
 
-	if not v:
-		v = None
+	if v == None:
 		if lines:
 			v = get_dict_v(idt, lines)
 	dic = { k: v }
@@ -124,6 +123,13 @@
 	except ValueError:
 		pass
 
+	if s == '[]':
+		return []
+	if s == '{}':
+		return {}
+	if s == '':
+		return None
+
 	lst = parse(s)
 	if len(lst) == 1 and s[:1] in qts:
 		s = s[1:-1]
@@ -158,10 +164,10 @@
 	lines = []
 	for (k, v) in dic.items():
 		s = dump_other(k, idt) + ':'
-		if type(v) == list:
+		if type(v) == list and v:
 			lines.append(s)
 			s = dump_list(v, idt)
-		elif type(v) == dict:
+		elif type(v) == dict and v:
 			lines.append(s)
 			s = dump_dict(v, idt+2)
 		else:
@@ -184,11 +190,17 @@
 		if q2 and q1:
 			s = s.replace("'", "\\'")
 			q1 = False
-		if q2 or q1 or cl or get_value(s) != obj:
+		if q2 or q1 or cl or get_value(s) != obj or s == '':
 			qt = '"' if q1 else "'"
 			s = qt + s + qt
 		return s
 
+	if type(obj) == list:
+		return '[]'
+
+	if type(obj) == dict:
+		return '{}'
+
 	return '{}'.format(obj)
 
 def dump_other(obj, idt):
@@ -196,9 +208,9 @@
 
 def dump_obj(obj, idt):
 	t = type(obj)
-	if t == dict:
+	if t == dict and obj:
 		return dump_dict(obj, idt)
-	if t == list:
+	if t == list and obj:
 		return dump_list(obj, idt)
 	return dump_other(obj, idt)