Merge 0fed0c38dd into cb0a24007f

This snapshot contains line wrapping problems, irrelevant comments,
extraneous output lines, and differences we're going to allow between
the online and print version.

The intention is to make this a baseline commit for chapter 7 that we
can diff against to find changes to consider sending to nostarch as tiny
tweaks.

Cargo.toml

@@ -2,7 +2,7 @@
 name = "rust-book"
 version = "0.0.1"
 description = "The Rust Book"
-edition = "2018"
+edition = "2021"
 
 [[bin]]
 name = "concat_chapters"

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/ch04-understanding-ownership/listing-04-01/src/main.rs

@@ -6,4 +6,4 @@ fn main() {
         // do stuff with s
     }                      // this scope is now over, and s is no longer valid
     // ANCHOR_END: here
-}
+}

listings/ch04-understanding-ownership/listing-04-03/src/main.rs

@@ -14,10 +14,10 @@ fn main() {
   // special happens.
 
 fn takes_ownership(some_string: String) { // some_string comes into scope
-    println!("{}", some_string);
+    println!("{some_string}");
 } // Here, some_string goes out of scope and `drop` is called. The backing
   // memory is freed.
 
 fn makes_copy(some_integer: i32) { // some_integer comes into scope
-    println!("{}", some_integer);
+    println!("{some_integer}");
 } // Here, some_integer goes out of scope. Nothing special happens.

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-01-can-mutate-string/src/main.rs

@@ -4,6 +4,6 @@ fn main() {
 
     s.push_str(", world!"); // push_str() appends a literal to a String
 
-    println!("{}", s); // This will print `hello, world!`
-                       // ANCHOR_END: here
+    println!("{s}"); // This will print `hello, world!`
+                     // ANCHOR_END: here
 }

listings/ch04-understanding-ownership/no-listing-04-cant-use-after-move/src/main.rs

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

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/ch04-understanding-ownership/no-listing-13-reference-scope-ends/src/main.rs

@@ -4,10 +4,10 @@ fn main() {
 
     let r1 = &s; // no problem
     let r2 = &s; // no problem
-    println!("{} and {}", r1, r2);
+    println!("{r1} and {r2}");
     // variables r1 and r2 will not be used after this point
 
     let r3 = &mut s; // no problem
-    println!("{}", r3);
+    println!("{r3}");
     // ANCHOR_END: here
 }

listings/ch04-understanding-ownership/no-listing-19-slice-error/src/main.rs

@@ -18,6 +18,6 @@ fn main() {
 
     s.clear(); // error!
 
-    println!("the first word is: {}", word);
+    println!("the first word is: {word}");
 }
 // ANCHOR_END: here

listings/ch05-using-structs-to-structure-related-data/listing-05-12/src/main.rs

@@ -10,5 +10,5 @@ fn main() {
         height: 50,
     };
 
-    println!("rect1 is {:?}", rect1);
+    println!("rect1 is {rect1:?}");
 }

listings/ch05-using-structs-to-structure-related-data/output-only-02-pretty-debug/src/main.rs

@@ -10,5 +10,5 @@ fn main() {
         height: 50,
     };
 
-    println!("rect1 is {:#?}", rect1);
+    println!("rect1 is {rect1:#?}");
 }

listings/ch06-enums-and-pattern-matching/listing-06-06/src/main.rs

@@ -2,7 +2,7 @@ fn main() {
     // ANCHOR: here
     let config_max = Some(3u8);
     match config_max {
-        Some(max) => println!("The maximum is configured to be {}", max),
+        Some(max) => println!("The maximum is configured to be {max}"),
         _ => (),
     }
     // ANCHOR_END: 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-12-if-let/src/main.rs

@@ -2,7 +2,7 @@ fn main() {
     // ANCHOR: here
     let config_max = Some(3u8);
     if let Some(max) = config_max {
-        println!("The maximum is configured to be {}", max);
+        println!("The maximum is configured to be {max}");
     }
     // ANCHOR_END: here
 }

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/ch07-managing-growing-projects/quick-reference-example/src/main.rs

@@ -4,5 +4,5 @@ pub mod garden;
 
 fn main() {
     let plant = Asparagus {};
-    println!("I'm growing {:?}!", plant);
+    println!("I'm growing {plant:?}!");
 }

listings/ch08-common-collections/listing-08-14/src/main.rs

@@ -15,5 +15,8 @@ fn main() {
     // ANCHOR: spanish
     let hello = String::from("Hola");
     // ANCHOR_END: spanish
+    // ANCHOR: bengali
+    let hello= String::from("নমস্কার");
+    //ANCHOR_END: bengali
     // ANCHOR_END: here
 }

listings/ch08-common-collections/listing-08-23/src/main.rs

@@ -7,6 +7,6 @@ fn main() {
     scores.insert(String::from("Blue"), 10);
     scores.insert(String::from("Blue"), 25);
 
-    println!("{:?}", scores);
+    println!("{scores:?}");
     // ANCHOR_END: here
 }

listings/ch08-common-collections/listing-08-24/src/main.rs

@@ -8,6 +8,6 @@ fn main() {
     scores.entry(String::from("Yellow")).or_insert(50);
     scores.entry(String::from("Blue")).or_insert(50);
 
-    println!("{:?}", scores);
+    println!("{scores:?}");
     // ANCHOR_END: here
 }

listings/ch08-common-collections/listing-08-25/src/main.rs

@@ -11,6 +11,6 @@ fn main() {
         *count += 1;
     }
 
-    println!("{:?}", map);
+    println!("{map:?}");
     // ANCHOR_END: here
 }

listings/ch09-error-handling/listing-09-04/src/main.rs

@@ -5,6 +5,6 @@ fn main() {
 
     let greeting_file = match greeting_file_result {
         Ok(file) => file,
-        Err(error) => panic!("Problem opening the file: {:?}", error),
+        Err(error) => panic!("Problem opening the file: {error:?}"),
     };
 }

listings/ch09-error-handling/listing-09-05/src/main.rs

@@ -9,10 +9,10 @@ fn main() {
         Err(error) => match error.kind() {
             ErrorKind::NotFound => match File::create("hello.txt") {
                 Ok(fc) => fc,
-                Err(e) => panic!("Problem creating the file: {:?}", e),
+                Err(e) => panic!("Problem creating the file: {e:?}"),
             },
             other_error => {
-                panic!("Problem opening the file: {:?}", other_error);
+                panic!("Problem opening the file: {other_error:?}");
             }
         },
     };

listings/ch10-generic-types-traits-and-lifetimes/listing-10-01/src/main.rs

@@ -10,7 +10,7 @@ fn main() {
         }
     }
 
-    println!("The largest number is {}", largest);
+    println!("The largest number is {largest}");
     // ANCHOR_END: here
     assert_eq!(*largest, 100);
     // ANCHOR: here

listings/ch10-generic-types-traits-and-lifetimes/listing-10-02/src/main.rs

@@ -9,7 +9,7 @@ fn main() {
         }
     }
 
-    println!("The largest number is {}", largest);
+    println!("The largest number is {largest}");
 
     let number_list = vec![102, 34, 6000, 89, 54, 2, 43, 8];
 
@@ -21,5 +21,5 @@ fn main() {
         }
     }
 
-    println!("The largest number is {}", largest);
+    println!("The largest number is {largest}");
 }

listings/ch10-generic-types-traits-and-lifetimes/listing-10-03/src/main.rs

@@ -15,7 +15,7 @@ fn main() {
     let number_list = vec![34, 50, 25, 100, 65];
 
     let result = largest(&number_list);
-    println!("The largest number is {}", result);
+    println!("The largest number is {result}");
     // ANCHOR_END: here
     assert_eq!(*result, 100);
     // ANCHOR: here
@@ -23,7 +23,7 @@ fn main() {
     let number_list = vec![102, 34, 6000, 89, 54, 2, 43, 8];
 
     let result = largest(&number_list);
-    println!("The largest number is {}", result);
+    println!("The largest number is {result}");
     // ANCHOR_END: here
     assert_eq!(*result, 6000);
     // ANCHOR: here

listings/ch10-generic-types-traits-and-lifetimes/listing-10-04/src/main.rs

@@ -27,7 +27,7 @@ fn main() {
     let number_list = vec![34, 50, 25, 100, 65];
 
     let result = largest_i32(&number_list);
-    println!("The largest number is {}", result);
+    println!("The largest number is {result}");
     // ANCHOR_END: here
     assert_eq!(*result, 100);
     // ANCHOR: here
@@ -35,7 +35,7 @@ fn main() {
     let char_list = vec!['y', 'm', 'a', 'q'];
 
     let result = largest_char(&char_list);
-    println!("The largest char is {}", result);
+    println!("The largest char is {result}");
     // ANCHOR_END: here
     assert_eq!(*result, 'y');
     // ANCHOR: here

listings/ch10-generic-types-traits-and-lifetimes/listing-10-05/src/main.rs

@@ -14,10 +14,10 @@ fn main() {
     let number_list = vec![34, 50, 25, 100, 65];
 
     let result = largest(&number_list);
-    println!("The largest number is {}", result);
+    println!("The largest number is {result}");
 
     let char_list = vec!['y', 'm', 'a', 'q'];
 
     let result = largest(&char_list);
-    println!("The largest char is {}", result);
+    println!("The largest char is {result}");
 }

listings/ch10-generic-types-traits-and-lifetimes/listing-10-16/src/main.rs

@@ -6,5 +6,5 @@ fn main() {
         r = &x;
     }
 
-    println!("r: {}", r);
+    println!("r: {r}");
 }

listings/ch10-generic-types-traits-and-lifetimes/listing-10-17/src/main.rs

@@ -6,5 +6,5 @@ fn main() {
         r = &x;           //  |       |
     }                     // -+       |
                           //          |
-    println!("r: {}", r); //          |
+    println!("r: {r}");   //          |
 }                         // ---------+

listings/ch10-generic-types-traits-and-lifetimes/listing-10-18/src/main.rs

@@ -3,6 +3,6 @@ fn main() {
                           //           |
     let r = &x;           // --+-- 'a  |
                           //   |       |
-    println!("r: {}", r); //   |       |
+    println!("r: {r}");   //   |       |
                           // --+       |
 }                         // ----------+

listings/ch10-generic-types-traits-and-lifetimes/listing-10-19/src/main.rs

@@ -3,5 +3,5 @@ fn main() {
     let string2 = "xyz";
 
     let result = longest(string1.as_str(), string2);
-    println!("The longest string is {}", result);
+    println!("The longest string is {result}");
 }

listings/ch10-generic-types-traits-and-lifetimes/listing-10-20/src/main.rs

@@ -3,7 +3,7 @@ fn main() {
     let string2 = "xyz";
 
     let result = longest(string1.as_str(), string2);
-    println!("The longest string is {}", result);
+    println!("The longest string is {result}");
 }
 
 // ANCHOR: here

listings/ch10-generic-types-traits-and-lifetimes/listing-10-21/src/main.rs

@@ -3,7 +3,7 @@ fn main() {
     let string2 = "xyz";
 
     let result = longest(string1.as_str(), string2);
-    println!("The longest string is {}", result);
+    println!("The longest string is {result}");
 }
 
 // ANCHOR: here

listings/ch10-generic-types-traits-and-lifetimes/listing-10-22/src/main.rs

@@ -5,7 +5,7 @@ fn main() {
     {
         let string2 = String::from("xyz");
         let result = longest(string1.as_str(), string2.as_str());
-        println!("The longest string is {}", result);
+        println!("The longest string is {result}");
     }
 }
 // ANCHOR_END: here

listings/ch10-generic-types-traits-and-lifetimes/listing-10-23/output.txt

@@ -9,8 +9,8 @@ error[E0597]: `string2` does not live long enough
   |                                            ^^^^^^^ borrowed value does not live long enough
 7 |     }
   |     - `string2` dropped here while still borrowed
-8 |     println!("The longest string is {}", result);
-  |                                          ------ borrow later used here
+8 |     println!("The longest string is {result}");
+  |                                      ------ borrow later used here
 
 For more information about this error, try `rustc --explain E0597`.
 error: could not compile `chapter10` (bin "chapter10") due to 1 previous error

listings/ch10-generic-types-traits-and-lifetimes/listing-10-23/src/main.rs

@@ -6,7 +6,7 @@ fn main() {
         let string2 = String::from("xyz");
         result = longest(string1.as_str(), string2.as_str());
     }
-    println!("The longest string is {}", result);
+    println!("The longest string is {result}");
 }
 // ANCHOR_END: here
 

listings/ch10-generic-types-traits-and-lifetimes/no-listing-08-only-one-reference-with-lifetime/src/main.rs

@@ -3,7 +3,7 @@ fn main() {
     let string2 = "efghijklmnopqrstuvwxyz";
 
     let result = longest(string1.as_str(), string2);
-    println!("The longest string is {}", result);
+    println!("The longest string is {result}");
 }
 
 // ANCHOR: here

listings/ch10-generic-types-traits-and-lifetimes/no-listing-09-unrelated-lifetime/src/main.rs

@@ -3,7 +3,7 @@ fn main() {
     let string2 = "xyz";
 
     let result = longest(string1.as_str(), string2);
-    println!("The longest string is {}", result);
+    println!("The longest string is {result}");
 }
 
 // ANCHOR: here

listings/ch10-generic-types-traits-and-lifetimes/no-listing-10-lifetimes-on-methods/src/main.rs

@@ -13,7 +13,7 @@ impl<'a> ImportantExcerpt<'a> {
 // ANCHOR: 3rd
 impl<'a> ImportantExcerpt<'a> {
     fn announce_and_return_part(&self, announcement: &str) -> &str {
-        println!("Attention please: {}", announcement);
+        println!("Attention please: {announcement}");
         self.part
     }
 }

listings/ch10-generic-types-traits-and-lifetimes/no-listing-11-generics-traits-and-lifetimes/src/main.rs

@@ -7,7 +7,7 @@ fn main() {
         string2,
         "Today is someone's birthday!",
     );
-    println!("The longest string is {}", result);
+    println!("The longest string is {result}");
 }
 
 // ANCHOR: here
@@ -21,7 +21,7 @@ fn longest_with_an_announcement<'a, T>(
 where
     T: Display,
 {
-    println!("Announcement! {}", ann);
+    println!("Announcement! {ann}");
     if x.len() > y.len() {
         x
     } else {

listings/ch11-writing-automated-tests/listing-11-10/src/lib.rs

@@ -1,5 +1,5 @@
 fn prints_and_returns_10(a: i32) -> i32 {
-    println!("I got the value {}", a);
+    println!("I got the value {a}");
     10
 }
 

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/ch11-writing-automated-tests/output-only-01-show-output/src/lib.rs

@@ -1,5 +1,5 @@
 pub fn prints_and_returns_10(a: i32) -> i32 {
-    println!("I got the value {}", a);
+    println!("I got the value {a}");
     10
 }
 

listings/ch12-an-io-project/listing-12-02/src/main.rs

@@ -6,6 +6,6 @@ fn main() {
     let query = &args[1];
     let file_path = &args[2];
 
-    println!("Searching for {}", query);
-    println!("In file {}", file_path);
+    println!("Searching for {query}");
+    println!("In file {file_path}");
 }

listings/ch12-an-io-project/listing-12-03/src/main.rs

@@ -6,6 +6,6 @@ fn main() {
     let query = &args[1];
     let file_path = &args[2];
 
-    println!("Searching for {}", query);
-    println!("In file {}", file_path);
+    println!("Searching for {query}");
+    println!("In file {file_path}");
 }

listings/ch12-an-io-project/listing-12-04/src/main.rs

@@ -10,9 +10,9 @@ fn main() {
     let query = &args[1];
     let file_path = &args[2];
 
-    println!("Searching for {}", query);
+    println!("Searching for {query}");
     // ANCHOR: here
-    println!("In file {}", file_path);
+    println!("In file {file_path}");
 
     let contents = fs::read_to_string(file_path)
         .expect("Should have been able to read the file");

listings/ch12-an-io-project/listing-12-05/src/main.rs

@@ -10,8 +10,8 @@ fn main() {
     // --snip--
     // ANCHOR_END: here
 
-    println!("Searching for {}", query);
-    println!("In file {}", file_path);
+    println!("Searching for {query}");
+    println!("In file {file_path}");
 
     let contents = fs::read_to_string(file_path)
         .expect("Should have been able to read the file");

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

@@ -1,10 +1,10 @@
 fn main() {
     let list = vec![1, 2, 3];
-    println!("Before defining closure: {:?}", list);
+    println!("Before defining closure: {list:?}");
 
-    let only_borrows = || println!("From closure: {:?}", list);
+    let only_borrows = || println!("From closure: {list:?}");
 
-    println!("Before calling closure: {:?}", list);
+    println!("Before calling closure: {list:?}");
     only_borrows();
-    println!("After calling closure: {:?}", list);
+    println!("After calling closure: {list:?}");
 }

listings/ch13-functional-features/listing-13-05/src/main.rs

@@ -1,9 +1,9 @@
 fn main() {
     let mut list = vec![1, 2, 3];
-    println!("Before defining closure: {:?}", list);
+    println!("Before defining closure: {list:?}");
 
     let mut borrows_mutably = || list.push(7);
 
     borrows_mutably();
-    println!("After calling closure: {:?}", list);
+    println!("After calling closure: {list:?}");
 }

listings/ch13-functional-features/listing-13-06/src/main.rs

@@ -2,9 +2,9 @@ use std::thread;
 
 fn main() {
     let list = vec![1, 2, 3];
-    println!("Before defining closure: {:?}", list);
+    println!("Before defining closure: {list:?}");
 
-    thread::spawn(move || println!("From thread: {:?}", list))
+    thread::spawn(move || println!("From thread: {list:?}"))
         .join()
         .unwrap();
 }

listings/ch13-functional-features/listing-13-07/src/main.rs

@@ -12,5 +12,5 @@ fn main() {
     ];
 
     list.sort_by_key(|r| r.width);
-    println!("{:#?}", list);
+    println!("{list:#?}");
 }

listings/ch13-functional-features/listing-13-08/src/main.rs

@@ -18,5 +18,5 @@ fn main() {
         sort_operations.push(value);
         r.width
     });
-    println!("{:#?}", list);
+    println!("{list:#?}");
 }

listings/ch13-functional-features/listing-13-09/src/main.rs

@@ -16,5 +16,5 @@ fn main() {
         num_sort_operations += 1;
         r.width
     });
-    println!("{:#?}, sorted in {num_sort_operations} operations", list);
+    println!("{list:#?}, sorted in {num_sort_operations} operations");
 }

listings/ch13-functional-features/listing-13-11/src/main.rs

@@ -5,7 +5,7 @@ fn main() {
     let v1_iter = v1.iter();
 
     for val in v1_iter {
-        println!("Got: {}", val);
+        println!("Got: {val}");
     }
     // ANCHOR_END: here
 }

listings/ch15-smart-pointers/listing-15-01/src/main.rs

@@ -1,4 +1,4 @@
 fn main() {
     let b = Box::new(5);
-    println!("b = {}", b);
+    println!("b = {b}");
 }

listings/ch15-smart-pointers/listing-15-24/src/main.rs

@@ -18,7 +18,7 @@ fn main() {
 
     *value.borrow_mut() += 10;
 
-    println!("a after = {:?}", a);
-    println!("b after = {:?}", b);
-    println!("c after = {:?}", c);
+    println!("a after = {a:?}");
+    println!("b after = {b:?}");
+    println!("c after = {c:?}");
 }

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/listing-16-03/output.txt

@@ -5,15 +5,15 @@ error[E0373]: closure may outlive the current function, but it borrows `v`, whic
   |
 6 |     let handle = thread::spawn(|| {
   |                                ^^ may outlive borrowed value `v`
-7 |         println!("Here's a vector: {:?}", v);
-  |                                           - `v` is borrowed here
+7 |         println!("Here's a vector: {v:?}");
+  |                                     - `v` is borrowed here
   |
 note: function requires argument type to outlive `'static`
  --> src/main.rs:6:18
   |
 6 |       let handle = thread::spawn(|| {
   |  __________________^
-7 | |         println!("Here's a vector: {:?}", v);
+7 | |         println!("Here's a vector: {v:?}");
 8 | |     });
   | |______^
 help: to force the closure to take ownership of `v` (and any other referenced variables), use the `move` keyword

listings/ch16-fearless-concurrency/listing-16-03/src/main.rs

@@ -4,7 +4,7 @@ fn main() {
     let v = vec![1, 2, 3];
 
     let handle = thread::spawn(|| {
-        println!("Here's a vector: {:?}", v);
+        println!("Here's a vector: {v:?}");
     });
 
     handle.join().unwrap();

listings/ch16-fearless-concurrency/listing-16-04/src/main.rs

@@ -4,7 +4,7 @@ fn main() {
     let v = vec![1, 2, 3];
 
     let handle = thread::spawn(|| {
-        println!("Here's a vector: {:?}", v);
+        println!("Here's a vector: {v:?}");
     });
 
     drop(v); // oh no!

listings/ch16-fearless-concurrency/listing-16-05/src/main.rs

@@ -4,7 +4,7 @@ fn main() {
     let v = vec![1, 2, 3];
 
     let handle = thread::spawn(move || {
-        println!("Here's a vector: {:?}", v);
+        println!("Here's a vector: {v:?}");
     });
 
     handle.join().unwrap();

listings/ch16-fearless-concurrency/listing-16-08/src/main.rs

@@ -10,5 +10,5 @@ fn main() {
     });
 
     let received = rx.recv().unwrap();
-    println!("Got: {}", received);
+    println!("Got: {received}");
 }

listings/ch16-fearless-concurrency/listing-16-09/output.txt

@@ -7,8 +7,8 @@ error[E0382]: borrow of moved value: `val`
    |             --- move occurs because `val` has type `String`, which does not implement the `Copy` trait
 9  |         tx.send(val).unwrap();
    |                 --- value moved here
-10 |         println!("val is {}", val);
-   |                               ^^^ value borrowed here after move
+10 |         println!("val is {val}");
+   |                           ^^^ value borrowed here after move
    |
    = note: this error originates in the macro `$crate::format_args_nl` which comes from the expansion of the macro `println` (in Nightly builds, run with -Z macro-backtrace for more info)
 help: consider cloning the value if the performance cost is acceptable

listings/ch16-fearless-concurrency/listing-16-09/src/main.rs

@@ -7,9 +7,9 @@ fn main() {
     thread::spawn(move || {
         let val = String::from("hi");
         tx.send(val).unwrap();
-        println!("val is {}", val);
+        println!("val is {val}");
     });
 
     let received = rx.recv().unwrap();
-    println!("Got: {}", received);
+    println!("Got: {received}");
 }

listings/ch16-fearless-concurrency/listing-16-10/src/main.rs

@@ -20,6 +20,6 @@ fn main() {
     });
 
     for received in rx {
-        println!("Got: {}", received);
+        println!("Got: {received}");
     }
 }

listings/ch16-fearless-concurrency/listing-16-11/src/main.rs

@@ -38,7 +38,7 @@ fn main() {
     });
 
     for received in rx {
-        println!("Got: {}", received);
+        println!("Got: {received}");
     }
 
     // --snip--

listings/ch16-fearless-concurrency/listing-16-12/src/main.rs

@@ -8,5 +8,5 @@ fn main() {
         *num = 6;
     }
 
-    println!("m = {:?}", m);
+    println!("m = {m:?}");
 }

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

@@ -4,7 +4,7 @@ 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));
         }
     });
@@ -12,7 +12,7 @@ fn main() {
     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/ch16-fearless-concurrency/output-only-01-move-drop/output.txt

@@ -8,8 +8,8 @@ error[E0382]: use of moved value: `v`
 5  |
 6  |     let handle = thread::spawn(move || {
    |                                ------- value moved into closure here
-7  |         println!("Here's a vector: {:?}", v);
-   |                                           - variable moved due to use in closure
+7  |         println!("Here's a vector: {v:?}");
+   |                                     - variable moved due to use in closure
 ...
 10 |     drop(v); // oh no!
    |          ^ value used here after move

listings/ch16-fearless-concurrency/output-only-01-move-drop/src/main.rs

@@ -4,7 +4,7 @@ fn main() {
     let v = vec![1, 2, 3];
 
     let handle = thread::spawn(move || {
-        println!("Here's a vector: {:?}", v);
+        println!("Here's a vector: {v:?}");
     });
 
     drop(v); // oh no!

listings/ch18-patterns-and-matching/listing-18-02/src/main.rs

@@ -7,7 +7,7 @@ fn main() {
     stack.push(3);
 
     while let Some(top) = stack.pop() {
-        println!("{}", top);
+        println!("{top}");
     }
     // ANCHOR_END: here
 }

listings/ch18-patterns-and-matching/listing-18-03/src/main.rs

@@ -3,7 +3,7 @@ fn main() {
     let v = vec!['a', 'b', 'c'];
 
     for (index, value) in v.iter().enumerate() {
-        println!("{} is at index {}", value, index);
+        println!("{value} is at index {index}");
     }
     // ANCHOR_END: here
 }

listings/ch18-patterns-and-matching/listing-18-07/src/main.rs

@@ -1,5 +1,5 @@
 fn print_coordinates(&(x, y): &(i32, i32)) {
-    println!("Current location: ({}, {})", x, y);
+    println!("Current location: ({x}, {y})");
 }
 
 fn main() {

listings/ch18-patterns-and-matching/listing-18-09/src/main.rs

@@ -2,7 +2,7 @@ fn main() {
     let some_option_value: Option<i32> = None;
     // ANCHOR: here
     if let Some(x) = some_option_value {
-        println!("{}", x);
+        println!("{x}");
     }
     // ANCHOR_END: here
 }

listings/ch18-patterns-and-matching/listing-18-10/src/main.rs

@@ -1,7 +1,7 @@
 fn main() {
     // ANCHOR: here
     if let x = 5 {
-        println!("{}", x);
+        println!("{x}");
     };
     // ANCHOR_END: here
 }

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

@@ -6,9 +6,9 @@ fn main() {
     match x {
         Some(50) => println!("Got 50"),
         Some(y) => println!("Matched, y = {y}"),
-        _ => println!("Default case, x = {:?}", x),
+        _ => println!("Default case, x = {x:?}"),
     }
 
-    println!("at the end: x = {:?}, y = {y}", x);
+    println!("at the end: x = {x:?}, y = {y}");
     // ANCHOR_END: here
 }

listings/ch18-patterns-and-matching/listing-18-15/src/main.rs

@@ -19,7 +19,7 @@ fn main() {
             println!("Text message: {text}");
         }
         Message::ChangeColor(r, g, b) => {
-            println!("Change the color to red {r}, green {g}, and blue {b}",)
+            println!("Change the color to red {r}, green {g}, and blue {b}")
         }
     }
 }

listings/ch18-patterns-and-matching/listing-18-17/src/main.rs

@@ -1,5 +1,5 @@
 fn foo(_: i32, y: i32) {
-    println!("This code only uses the y parameter: {}", y);
+    println!("This code only uses the y parameter: {y}");
 }
 
 fn main() {

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

@@ -12,6 +12,6 @@ fn main() {
         }
     }
 
-    println!("setting is {:?}", setting_value);
+    println!("setting is {setting_value:?}");
     // ANCHOR_END: here
 }

listings/ch18-patterns-and-matching/listing-18-21/src/main.rs

@@ -6,6 +6,6 @@ fn main() {
         println!("found a string");
     }
 
-    println!("{:?}", s);
+    println!("{s:?}");
     // ANCHOR_END: here
 }

listings/ch18-patterns-and-matching/listing-18-22/src/main.rs

@@ -6,6 +6,6 @@ fn main() {
         println!("found a string");
     }
 
-    println!("{:?}", s);
+    println!("{s:?}");
     // ANCHOR_END: here
 }

listings/ch18-patterns-and-matching/listing-18-23/src/main.rs

@@ -9,7 +9,7 @@ fn main() {
     let origin = Point { x: 0, y: 0, z: 0 };
 
     match origin {
-        Point { x, .. } => println!("x is {}", x),
+        Point { x, .. } => println!("x is {x}"),
     }
     // ANCHOR_END: here
 }

listings/ch18-patterns-and-matching/listing-18-25/src/main.rs

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

listings/ch18-patterns-and-matching/listing-18-26/src/main.rs

@@ -3,8 +3,8 @@ fn main() {
     let num = Some(4);
 
     match num {
-        Some(x) if x % 2 == 0 => println!("The number {} is even", x),
-        Some(x) => println!("The number {} is odd", x),
+        Some(x) if x % 2 == 0 => println!("The number {x} is even"),
+        Some(x) => println!("The number {x} is odd"),
         None => (),
     }
     // ANCHOR_END: here

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

@@ -5,8 +5,8 @@ fn main() {
     match x {
         Some(50) => println!("Got 50"),
         Some(n) if n == y => println!("Matched, n = {n}"),
-        _ => println!("Default case, x = {:?}", x),
+        _ => println!("Default case, x = {x:?}"),
     }
 
-    println!("at the end: x = {:?}, y = {y}", x);
+    println!("at the end: x = {x:?}, y = {y}");
 }

listings/ch18-patterns-and-matching/listing-18-29/src/main.rs

@@ -9,11 +9,11 @@ fn main() {
     match msg {
         Message::Hello {
             id: id_variable @ 3..=7,
-        } => println!("Found an id in range: {}", id_variable),
+        } => println!("Found an id in range: {id_variable}"),
         Message::Hello { id: 10..=12 } => {
             println!("Found an id in another range")
         }
-        Message::Hello { id } => println!("Found some other id: {}", id),
+        Message::Hello { id } => println!("Found some other id: {id}"),
     }
     // ANCHOR_END: here
 }

listings/ch19-advanced-features/listing-19-09/src/main.rs

@@ -1,5 +1,5 @@
 static HELLO_WORLD: &str = "Hello, world!";
 
 fn main() {
-    println!("name is: {}", HELLO_WORLD);
+    println!("name is: {HELLO_WORLD}");
 }

listings/ch19-advanced-features/listing-19-10/src/main.rs

@@ -10,6 +10,6 @@ fn main() {
     add_to_count(3);
 
     unsafe {
-        println!("COUNTER: {}", COUNTER);
+        println!("COUNTER: {COUNTER}");
     }
 }

listings/ch19-advanced-features/listing-19-22/src/main.rs

@@ -7,7 +7,7 @@ trait OutlinePrint: fmt::Display {
         let len = output.len();
         println!("{}", "*".repeat(len + 4));
         println!("*{}*", " ".repeat(len + 2));
-        println!("* {} *", output);
+        println!("* {output} *");
         println!("*{}*", " ".repeat(len + 2));
         println!("{}", "*".repeat(len + 4));
     }

listings/ch19-advanced-features/listing-19-23/src/main.rs

@@ -10,5 +10,5 @@ impl fmt::Display for Wrapper {
 
 fn main() {
     let w = Wrapper(vec![String::from("hello"), String::from("world")]);
-    println!("w = {}", w);
+    println!("w = {w}");
 }

listings/ch19-advanced-features/listing-19-27/src/main.rs

@@ -9,5 +9,5 @@ fn do_twice(f: fn(i32) -> i32, arg: i32) -> i32 {
 fn main() {
     let answer = do_twice(add_one, 5);
 
-    println!("The answer is: {}", answer);
+    println!("The answer is: {answer}");
 }

listings/ch19-advanced-features/no-listing-02-impl-outlineprint-for-point/src/main.rs

@@ -6,7 +6,7 @@ trait OutlinePrint: fmt::Display {
         let len = output.len();
         println!("{}", "*".repeat(len + 4));
         println!("*{}*", " ".repeat(len + 2));
-        println!("* {} *", output);
+        println!("* {output} *");
         println!("*{}*", " ".repeat(len + 2));
         println!("{}", "*".repeat(len + 4));
     }

listings/ch19-advanced-features/no-listing-03-impl-display-for-point/src/main.rs

@@ -4,7 +4,7 @@ trait OutlinePrint: fmt::Display {
         let len = output.len();
         println!("{}", "*".repeat(len + 4));
         println!("*{}*", " ".repeat(len + 2));
-        println!("* {} *", output);
+        println!("* {output} *");
         println!("*{}*", " ".repeat(len + 2));
         println!("{}", "*".repeat(len + 4));
     }

listings/ch20-web-server/listing-20-02/src/main.rs

@@ -21,5 +21,5 @@ fn handle_connection(mut stream: TcpStream) {
         .take_while(|line| !line.is_empty())
         .collect();
 
-    println!("Request: {:#?}", http_request);
+    println!("Request: {http_request:#?}");
 }