补充不完整的例子

tutorial/09_lifetimes.md

@@ -201,9 +201,17 @@ impl<'a> ImportantExcerpt<'a> {
 fn main() {
     let novel = String::from("Call me Ishmael. Some years ago...");
     let first_sentence = novel.split('.').next().expect("Could not find a '.'");
-    let i = ImportantExcerpt {
-        part: first_sentence,
-    };
+
+    let res;
+    {
+        let i = ImportantExcerpt {
+            part: first_sentence,
+        };
+        res = i.announce_and_return_part("生命周期");
+        println!("{}", res);
+    }
+    // 根据上面的规则3，res的生命周期由 i 决定。此处 i 已经离开作用域，故 res 无效
+    // println!("{}", res);
 }
 ```
 

tutorial/10_trait_objects.md

@@ -413,7 +413,7 @@ fn benchmark() {
     let start = Instant::now();
     let mut sum: i64 = 0;
     for _ in 0..1000000 {
-        sum += adder.compute(10); // 隐式转换 i32 到 i64
+        sum += adder.compute(10) as i64; // 隐式转换 i32 到 i64
     }
     println!("静态分发时间: {:?}", start.elapsed());
     println!("静态分发结果 (i32): {}", sum);
@@ -568,23 +568,23 @@ fn use_service(service: &mut dyn Service, input: &str) -> String {
 }
 
 // 2. 必要时才转移所有权
-struct ServiceManager {
-    services: Vec<Box<dyn Service>>,
+struct ServiceManager<'s> {
+    services: Vec<Box<dyn Service + 's>>,
 }
 
-impl ServiceManager {
+impl<'s> ServiceManager<'s> {
     // R: 提供只读访问
-    fn find_service(&self, index: usize) -> Option<&dyn Service> {
+    fn find_service(&self, index: usize) -> Option<&(dyn Service + 's)> {
         self.services.get(index).map(|s| s.as_ref())
     }
 
     // W: 提供可变访问
-    fn find_service_mut(&mut self, index: usize) -> Option<&mut dyn Service> {
+    fn find_service_mut(&mut self, index: usize) -> Option<&mut (dyn Service+'s)> {
         self.services.get_mut(index).map(|s| s.as_mut())
     }
 
     // O: 转移所有权（谨慎使用）
-    fn extract_service(&mut self, index: usize) -> Option<Box<dyn Service>> {
+    fn extract_service(&mut self, index: usize) -> Option<Box<dyn Service + 's>> {
         if index < self.services.len() {
             Some(self.services.remove(index))
         } else {