new operator 'groupby'

kern/dict-type.go

@@ -143,13 +143,12 @@ func (dict *DictType) HasKey(target any) (ok bool) {
 	return
 }
 
-func (dict *DictType) SetItem(key any, value any) (err error) {
+func (dict *DictType) SetItem(key any, value any) {
 	(*dict)[key] = value
-	return
 }
 
-func (dict *DictType) GetItem(key any) (value any, err error) {
-	value = (*dict)[key]
+func (dict *DictType) GetItem(key any) (value any, exists bool) {
+	value, exists = (*dict)[key]
 	return
 }
 
@@ -169,6 +168,24 @@ func (dict *DictType) Merge(second *DictType) {
 	}
 }
 
+func (dict *DictType) Equals(dict2 DictType) (answer bool) {
+	if dict2 != nil && len(*dict) == len(dict2) {
+		answer = true
+		for key, value1 := range *dict {
+			if value2, exists := dict2.GetItem(key); exists {
+				if !Equal(value1, value2) {
+					answer = false
+					break
+				}
+			} else {
+				answer = false
+				break
+			}
+		}
+	}
+	return
+}
+
 ////////////////
 
 type DictFormat interface {