new operator ':=', it assigns a value to a variable by deep copy

t_operator_test.go

@@ -54,7 +54,7 @@ func TestOperatorInsert(t *testing.T) {
 		/*   6 */ {`[] >> ["a", "b"]`, kern.NewListA("a", "b"), nil},
 		/*   7 */ {`["a", "b"] << $([1,2,3])`, kern.NewListA("a", "b", int64(1), int64(2), int64(3)), nil},
 		/*   8 */ {`L=["a", "b"]; L << $([1,2,3])`, kern.NewListA("a", "b", int64(1), int64(2), int64(3)), nil},
-		/*   9 */ {`L=["a", "b"]; L << $([1,2,3]); L`, kern.NewListA("a", "b", int64(1), int64(2), int64(3)), nil},
+		/*   9 */ {`L=["a", "b"]; L << $([1,2,3]); L`, kern.NewListA("a", "b"), nil},
 		/*  10 */ {`L << $([1,2,3])`, nil, `undefined variable or function "L"`},
 	}
 
@@ -62,6 +62,19 @@ func TestOperatorInsert(t *testing.T) {
 	runTestSuite(t, section, inputs)
 }
 
+func TestOperatorDeepAssign(t *testing.T) {
+	section := "Operator-DeepAssign"
+	inputs := []inputType{
+		/*   1 */ {`DD={"uno": 1, "due": 2}; D=DD; D["uno"]=11; DD`, kern.NewDict(map[any]any{"uno": int64(11), "due": int64(2)}), nil},
+		/*   2 */ {`DD={"uno": 1, "due": 2}; D:=DD; D["uno"]=11; DD`, kern.NewDict(map[any]any{"uno": int64(1), "due": int64(2)}), nil},
+		/*   3 */ {`LL=["a", "b"]; L=LL; L[0]="x"; LL`, kern.NewListA("x", "b"), nil},
+		/*   4 */ {`LL=["a", "b"]; L:=LL; L[0]="x"; LL`, kern.NewListA("a", "b"), nil},
+	}
+
+	// runTestSuiteSpec(t, section, inputs, 4)
+	runTestSuite(t, section, inputs)
+}
+
 func TestOperatorDigest(t *testing.T) {
 	section := "Operator-Digest"
 	inputs := []inputType{