Use v1.58 captured ident formatting in examples

Per #3047, use captured identifiers instead of the positional ones for some examples, e.g.

```diff
-  println!("Worker {} got a job; executing.", id);
+  println!("Worker {id} got a job; executing.");
```

listings/ch02-guessing-game-tutorial/listing-02-01/src/main.rs

@@ -25,7 +25,7 @@ fn main() {
     // ANCHOR_END: expect
 
     // ANCHOR: print_guess
-    println!("You guessed: {}", guess);
+    println!("You guessed: {guess}");
     // ANCHOR_END: print_guess
 }
 // ANCHOR: all

listings/ch02-guessing-game-tutorial/listing-02-02/src/main.rs

@@ -11,5 +11,5 @@ fn main() {
         .read_line(&mut guess)
         .expect("Failed to read line");
 
-    println!("You guessed: {}", guess);
+    println!("You guessed: {guess}");
 }

listings/ch03-common-programming-concepts/listing-03-03/src/main.rs

@@ -2,7 +2,7 @@ fn main() {
     let mut number = 3;
 
     while number != 0 {
-        println!("{}!", number);
+        println!("{number}!");
 
         number -= 1;
     }

listings/ch03-common-programming-concepts/no-listing-18-functions-with-multiple-parameters/src/main.rs

@@ -3,5 +3,5 @@ fn main() {
 }
 
 fn print_labeled_measurement(value: i32, unit_label: char) {
-    println!("The measurement is: {}{}", value, unit_label);
+    println!("The measurement is: {value}{unit_label}");
 }

listings/ch03-common-programming-concepts/no-listing-34-for-range/src/main.rs

@@ -1,6 +1,6 @@
 fn main() {
     for number in (1..4).rev() {
-        println!("{}!", number);
+        println!("{number}!");
     }
     println!("LIFTOFF!!!");
 }

listings/ch04-understanding-ownership/listing-04-05/src/main.rs

@@ -3,7 +3,7 @@ fn main() {
 
     let (s2, len) = calculate_length(s1);
 
-    println!("The length of '{}' is {}.", s2, len);
+    println!("The length of '{s2}' is {len}.");
 }
 
 fn calculate_length(s: String) -> (String, usize) {

listings/ch04-understanding-ownership/no-listing-05-clone/src/main.rs

@@ -3,6 +3,6 @@ fn main() {
     let s1 = String::from("hello");
     let s2 = s1.clone();
 
-    println!("s1 = {}, s2 = {}", s1, s2);
+    println!("s1 = {s1}, s2 = {s2}");
     // ANCHOR_END: here
 }

listings/ch04-understanding-ownership/no-listing-06-copy/src/main.rs

@@ -3,6 +3,6 @@ fn main() {
     let x = 5;
     let y = x;
 
-    println!("x = {}, y = {}", x, y);
+    println!("x = {x}, y = {y}");
     // ANCHOR_END: here
 }

listings/ch04-understanding-ownership/no-listing-07-reference/src/main.rs

@@ -6,7 +6,7 @@ fn main() {
     let len = calculate_length(&s1);
     // ANCHOR_END: here
 
-    println!("The length of '{}' is {}.", s1, len);
+    println!("The length of '{s1}' is {len}.");
 }
 
 fn calculate_length(s: &String) -> usize {

listings/ch04-understanding-ownership/no-listing-08-reference-with-annotations/src/main.rs

@@ -3,7 +3,7 @@ fn main() {
 
     let len = calculate_length(&s1);
 
-    println!("The length of '{}' is {}.", s1, len);
+    println!("The length of '{s1}' is {len}.");
 }
 
 // ANCHOR: here

listings/ch06-enums-and-pattern-matching/no-listing-09-variable-in-pattern/src/main.rs

@@ -19,7 +19,7 @@ fn value_in_cents(coin: Coin) -> u8 {
         Coin::Nickel => 5,
         Coin::Dime => 10,
         Coin::Quarter(state) => {
-            println!("State quarter from {:?}!", state);
+            println!("State quarter from {state:?}!");
             25
         }
     }

listings/ch06-enums-and-pattern-matching/no-listing-13-count-and-announce-match/src/main.rs

@@ -17,7 +17,7 @@ fn main() {
     // ANCHOR: here
     let mut count = 0;
     match coin {
-        Coin::Quarter(state) => println!("State quarter from {:?}!", state),
+        Coin::Quarter(state) => println!("State quarter from {state:?}!"),
         _ => count += 1,
     }
     // ANCHOR_END: here

listings/ch06-enums-and-pattern-matching/no-listing-14-count-and-announce-if-let-else/src/main.rs

@@ -17,7 +17,7 @@ fn main() {
     // ANCHOR: here
     let mut count = 0;
     if let Coin::Quarter(state) = coin {
-        println!("State quarter from {:?}!", state);
+        println!("State quarter from {state:?}!");
     } else {
         count += 1;
     }

listings/ch11-writing-automated-tests/no-listing-05-greeter/src/lib.rs

@@ -1,5 +1,5 @@
 pub fn greeting(name: &str) -> String {
-    format!("Hello {}!", name)
+    format!("Hello {name}!")
 }
 
 #[cfg(test)]

listings/ch13-functional-features/listing-13-04/src/main.rs

@@ -12,13 +12,13 @@ fn generate_workout(intensity: u32, random_number: u32) {
     let expensive_result = simulated_expensive_calculation(intensity);
 
     if intensity < 25 {
-        println!("Today, do {} pushups!", expensive_result);
-        println!("Next, do {} situps!", expensive_result);
+        println!("Today, do {expensive_result} pushups!");
+        println!("Next, do {expensive_result} situps!");
     } else {
         if random_number == 3 {
             println!("Take a break today! Remember to stay hydrated!");
         } else {
-            println!("Today, run for {} minutes!", expensive_result);
+            println!("Today, run for {expensive_result} minutes!");
         }
     }
 }

listings/ch15-smart-pointers/listing-15-11/src/main.rs

@@ -1,6 +1,6 @@
 // ANCHOR: here
 fn hello(name: &str) {
-    println!("Hello, {}!", name);
+    println!("Hello, {name}!");
 }
 // ANCHOR_END: here
 

listings/ch15-smart-pointers/listing-15-12/src/main.rs

@@ -17,7 +17,7 @@ impl<T> MyBox<T> {
 }
 
 fn hello(name: &str) {
-    println!("Hello, {}!", name);
+    println!("Hello, {name}!");
 }
 
 // ANCHOR: here

listings/ch15-smart-pointers/listing-15-13/src/main.rs

@@ -17,7 +17,7 @@ impl<T> MyBox<T> {
 }
 
 fn hello(name: &str) {
-    println!("Hello, {}!", name);
+    println!("Hello, {name}!");
 }
 
 // ANCHOR: here

listings/ch16-fearless-concurrency/listing-16-01/src/main.rs

@@ -4,13 +4,13 @@ use std::time::Duration;
 fn main() {
     thread::spawn(|| {
         for i in 1..10 {
-            println!("hi number {} from the spawned thread!", i);
+            println!("hi number {i} from the spawned thread!");
             thread::sleep(Duration::from_millis(1));
         }
     });
 
     for i in 1..5 {
-        println!("hi number {} from the main thread!", i);
+        println!("hi number {i} from the main thread!");
         thread::sleep(Duration::from_millis(1));
     }
 }

listings/ch16-fearless-concurrency/listing-16-02/src/main.rs

@@ -4,13 +4,13 @@ use std::time::Duration;
 fn main() {
     let handle = thread::spawn(|| {
         for i in 1..10 {
-            println!("hi number {} from the spawned thread!", i);
+            println!("hi number {i} from the spawned thread!");
             thread::sleep(Duration::from_millis(1));
         }
     });
 
     for i in 1..5 {
-        println!("hi number {} from the main thread!", i);
+        println!("hi number {i} from the main thread!");
         thread::sleep(Duration::from_millis(1));
     }
 

listings/ch16-fearless-concurrency/no-listing-01-join-too-early/src/main.rs

@@ -4,15 +4,15 @@ use std::time::Duration;
 fn main() {
     let handle = thread::spawn(|| {
         for i in 1..10 {
-            println!("hi number {} from the spawned thread!", i);
+            println!("hi number {i} from the spawned thread!");
             thread::sleep(Duration::from_millis(1));
         }
     });
 
     handle.join().unwrap();
 
     for i in 1..5 {
-        println!("hi number {} from the main thread!", i);
+        println!("hi number {i} from the main thread!");
         thread::sleep(Duration::from_millis(1));
     }
 }

listings/ch18-patterns-and-matching/listing-18-01/src/main.rs

@@ -4,7 +4,7 @@ fn main() {
     let age: Result<u8, _> = "34".parse();
 
     if let Some(color) = favorite_color {
-        println!("Using your favorite color, {}, as the background", color);
+        println!("Using your favorite color, {color}, as the background");
     } else if is_tuesday {
         println!("Tuesday is green day!");
     } else if let Ok(age) = age {

listings/ch18-patterns-and-matching/listing-18-11/src/main.rs

@@ -5,10 +5,10 @@ fn main() {
 
     match x {
         Some(50) => println!("Got 50"),
-        Some(y) => println!("Matched, y = {:?}", y),
-        _ => println!("Default case, x = {:?}", x),
+        Some(y) => println!("Matched, y = {y:?}"),
+        _ => println!("Default case, x = {x:?}"),
     }
 
-    println!("at the end: x = {:?}, y = {:?}", x, y);
+    println!("at the end: x = {x:?}, y = {y:?}");
     // ANCHOR_END: here
 }

listings/ch18-patterns-and-matching/listing-18-19/src/main.rs

@@ -4,7 +4,7 @@ fn main() {
 
     match numbers {
         (first, _, third, _, fifth) => {
-            println!("Some numbers: {}, {}, {}", first, third, fifth)
+            println!("Some numbers: {first}, {third}, {fifth}")
         }
     }
     // ANCHOR_END: here

listings/ch18-patterns-and-matching/listing-18-24/src/main.rs

@@ -3,7 +3,7 @@ fn main() {
 
     match numbers {
         (first, .., last) => {
-            println!("Some numbers: {}, {}", first, last);
+            println!("Some numbers: {first}, {last}");
         }
     }
 }

listings/ch18-patterns-and-matching/listing-18-27/src/main.rs

@@ -4,9 +4,9 @@ fn main() {
 
     match x {
         Some(50) => println!("Got 50"),
-        Some(n) if n == y => println!("Matched, n = {}", n),
-        _ => println!("Default case, x = {:?}", x),
+        Some(n) if n == y => println!("Matched, n = {n}"),
+        _ => println!("Default case, x = {x:?}"),
     }
 
-    println!("at the end: x = {:?}, y = {}", x, y);
+    println!("at the end: x = {x:?}, y = {y}");
 }

listings/ch20-web-server/listing-20-20/src/lib.rs

@@ -57,7 +57,7 @@ impl Worker {
         let thread = thread::spawn(move || loop {
             let job = receiver.lock().unwrap().recv().unwrap();
 
-            println!("Worker {} got a job; executing.", id);
+            println!("Worker {id} got a job; executing.");
 
             job();
         });

listings/ch20-web-server/listing-20-21/src/lib.rs

@@ -55,7 +55,7 @@ impl Worker {
     fn new(id: usize, receiver: Arc<Mutex<mpsc::Receiver<Job>>>) -> Worker {
         let thread = thread::spawn(move || {
             while let Ok(job) = receiver.lock().unwrap().recv() {
-                println!("Worker {} got a job; executing.", id);
+                println!("Worker {id} got a job; executing.");
 
                 job();
             }

listings/ch20-web-server/listing-20-22/src/lib.rs

@@ -66,7 +66,7 @@ impl Worker {
         let thread = thread::spawn(move || loop {
             let job = receiver.lock().unwrap().recv().unwrap();
 
-            println!("Worker {} got a job; executing.", id);
+            println!("Worker {id} got a job; executing.");
 
             job();
         });

listings/ch20-web-server/listing-20-23/src/lib.rs

@@ -86,12 +86,12 @@ impl Worker {
 
             match message {
                 Message::NewJob(job) => {
-                    println!("Worker {} got a job; executing.", id);
+                    println!("Worker {id} got a job; executing.");
 
                     job();
                 }
                 Message::Terminate => {
-                    println!("Worker {} was told to terminate.", id);
+                    println!("Worker {id} was told to terminate.");
 
                     break;
                 }

listings/ch20-web-server/listing-20-24/src/lib.rs

@@ -83,12 +83,12 @@ impl Worker {
 
             match message {
                 Message::NewJob(job) => {
-                    println!("Worker {} got a job; executing.", id);
+                    println!("Worker {id} got a job; executing.");
 
                     job();
                 }
                 Message::Terminate => {
-                    println!("Worker {} was told to terminate.", id);
+                    println!("Worker {id} was told to terminate.");
 
                     break;
                 }

listings/ch20-web-server/listing-20-25/src/lib.rs

@@ -81,12 +81,12 @@ impl Worker {
 
             match message {
                 Message::NewJob(job) => {
-                    println!("Worker {} got a job; executing.", id);
+                    println!("Worker {id} got a job; executing.");
 
                     job();
                 }
                 Message::Terminate => {
-                    println!("Worker {} was told to terminate.", id);
+                    println!("Worker {id} was told to terminate.");
 
                     break;
                 }

listings/ch20-web-server/no-listing-04-update-worker-definition/src/lib.rs

@@ -66,7 +66,7 @@ impl Worker {
         let thread = thread::spawn(move || loop {
             let job = receiver.lock().unwrap().recv().unwrap();
 
-            println!("Worker {} got a job; executing.", id);
+            println!("Worker {id} got a job; executing.");
 
             job();
         });

listings/ch20-web-server/no-listing-05-fix-worker-new/src/lib.rs

@@ -68,7 +68,7 @@ impl Worker {
         let thread = thread::spawn(move || loop {
             let job = receiver.lock().unwrap().recv().unwrap();
 
-            println!("Worker {} got a job; executing.", id);
+            println!("Worker {id} got a job; executing.");
 
             job();
         });

listings/ch20-web-server/no-listing-06-fix-threadpool-drop/src/lib.rs

@@ -68,7 +68,7 @@ impl Worker {
         let thread = thread::spawn(move || loop {
             let job = receiver.lock().unwrap().recv().unwrap();
 
-            println!("Worker {} got a job; executing.", id);
+            println!("Worker {id} got a job; executing.");
 
             job();
         });

listings/ch20-web-server/no-listing-07-define-message-enum/src/lib.rs

@@ -73,7 +73,7 @@ impl Worker {
         let thread = thread::spawn(move || loop {
             let job = receiver.lock().unwrap().recv().unwrap();
 
-            println!("Worker {} got a job; executing.", id);
+            println!("Worker {id} got a job; executing.");
 
             job();
         });

listings/ch20-web-server/no-listing-08-final-code/src/lib.rs

@@ -81,12 +81,12 @@ impl Worker {
 
             match message {
                 Message::NewJob(job) => {
-                    println!("Worker {} got a job; executing.", id);
+                    println!("Worker {id} got a job; executing.");
 
                     job();
                 }
                 Message::Terminate => {
-                    println!("Worker {} was told to terminate.", id);
+                    println!("Worker {id} was told to terminate.");
 
                     break;
                 }