Inline all format arguments

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/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     }                      // this scope is now over, and s is no longer valid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/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-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-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/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-08-23/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

@@ -15,15 +15,15 @@ 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
 
     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

@@ -27,15 +27,15 @@ 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
 
     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/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");