diff --git a/src/expression/Parse.go b/src/expression/Parse.go
index 0c30be3..f4e261a 100644
--- a/src/expression/Parse.go
+++ b/src/expression/Parse.go
@@ -71,7 +71,9 @@ loop:
 				root = node
 			}
 
-			cursor = node
+			if !cursor.Token.Kind.IsUnaryOperator() || !node.Token.Kind.IsUnaryOperator() {
+				cursor = node
+			}
 		}
 
 		i++
diff --git a/src/expression/Parse_test.go b/src/expression/Parse_test.go
index ca8ec20..ad139c9 100644
--- a/src/expression/Parse_test.go
+++ b/src/expression/Parse_test.go
@@ -59,17 +59,21 @@ func TestParse(t *testing.T) {
 
 		{"Unary not", "!", "!"},
 		{"Unary not 2", "!a", "(! a)"},
-		{"Unary not 3", "!(!a)", "(! (! a))"},
-		{"Unary not 4", "!(a||b)", "(! (|| a b))"},
-		{"Unary not 5", "a || !b", "(|| a (! b))"},
+		{"Unary not 3", "!!a", "(! (! a))"},
+		{"Unary not 4", "!!!a", "(! (! (! a)))"},
+		{"Unary not 5", "!(!a)", "(! (! a))"},
+		{"Unary not 6", "!(a||b)", "(! (|| a b))"},
+		{"Unary not 7", "a || !b", "(|| a (! b))"},
 
 		{"Unary minus", "-", "-"},
 		{"Unary minus 2", "-a", "(- a)"},
-		{"Unary minus 3", "-(-a)", "(- (- a))"},
-		{"Unary minus 4", "-a+b", "(+ (- a) b)"},
-		{"Unary minus 5", "-(a+b)", "(- (+ a b))"},
-		{"Unary minus 6", "a + -b", "(+ a (- b))"},
-		{"Unary minus 7", "-a + -b", "(+ (- a) (- b))"},
+		{"Unary minus 3", "--a", "(- (- a))"},
+		{"Unary minus 4", "---a", "(- (- (- a)))"},
+		{"Unary minus 5", "-(-a)", "(- (- a))"},
+		{"Unary minus 6", "-a+b", "(+ (- a) b)"},
+		{"Unary minus 7", "-(a+b)", "(- (+ a b))"},
+		{"Unary minus 8", "a + -b", "(+ a (- b))"},
+		{"Unary minus 9", "-a + -b", "(+ (- a) (- b))"},
 
 		{"Assign bitwise operation", "a|=b", "(|= a b)"},
 		{"Assign bitwise operation 2", "a|=b<<c", "(|= a (<< b c))"},