test(exp/container/queue): add example test case for All.

go/exp/container/queue/example_test.go

@@ -11,42 +11,52 @@ import (
 )
 
 func Example() {
-	// Create a new list and put some numbers in it.
-	var l queue.Queue[int]
-	l.PushBack(1)
-	l.PushBack(2)
-	l.PushBack(3)
-	l.PushBack(4)
+	// Create a new queue and put some numbers in it.
+	var l1 queue.Queue[int]
+	l1.PushBack(1)
+	l1.PushBack(2)
+	l1.PushBack(3)
+	l1.PushBack(4)
 
 	var l2 queue.Queue[int]
 	l2.PushBack(5)
 	l2.PushBack(6)
 	l2.PushBack(7)
 	l2.PushBack(8)
 
-	l.PushBackSeq(l2.Values())
-
-	l2.TrimFrontFunc(func(e int) bool {
-		return e%2 == 1
-	})
-	// Iterate through list and print its contents.
-	for e := range l.Values() {
-		fmt.Println(e)
+	l1.PushBackSeq(l2.Values())
+
+	var s []int
+	if cleaned := l2.TrimFrontFunc(func(e int) bool {
+		if e%2 == 1 {
+			s = append(s, e)
+			return true
+		}
+		return false
+	}); cleaned {
+		fmt.Printf("l2: clean leading: %v\n", s)
+	}
+	// Iterate through queue and print its contents.
+	for i, e := range l1.All() {
+		fmt.Printf("l1[%d]: %d\n", i, e)
 	}
+	var i int
 	for e := range l2.Values() {
-		fmt.Println(e)
+		fmt.Printf("l2[%d]: %d\n", i, e)
+		i++
 	}
 
 	// Output:
-	// 1
-	// 2
-	// 3
-	// 4
-	// 5
-	// 6
-	// 7
-	// 8
-	// 6
-	// 7
-	// 8
+	// l2: clean leading: [5]
+	// l1[0]: 1
+	// l1[1]: 2
+	// l1[2]: 3
+	// l1[3]: 4
+	// l1[4]: 5
+	// l1[5]: 6
+	// l1[6]: 7
+	// l1[7]: 8
+	// l2[0]: 6
+	// l2[1]: 7
+	// l2[2]: 8
 }