Inline all format arguments

The inlined format arguments are a bit easier to understand,
especially for those familiar with the other languages (python, js).

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     }                      // this scope is now over, and s is no longer valid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/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!`
+    println!("{s}"); // This will print `hello, world!`
                        // ANCHOR_END: here
 }

listings/ch04-understanding-ownership/no-listing-04-cant-use-after-move/output.txt

@@ -7,9 +7,9 @@ error[E0382]: borrow of moved value: `s1`
   |         -- move occurs because `s1` has type `String`, which does not implement the `Copy` trait
 3 |     let s2 = s1;
   |              -- value moved here
-4 | 
-5 |     println!("{}, world!", s1);
-  |                            ^^ value borrowed here after move
+4 |
+5 |     println!("{s1}, world!");
+  |                ^^ value borrowed here after move
   |
   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 

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/output.txt

@@ -5,12 +5,12 @@ error[E0502]: cannot borrow `s` as mutable because it is also borrowed as immuta
    |
 16 |     let word = first_word(&s);
    |                           -- immutable borrow occurs here
-17 | 
+17 |
 18 |     s.clear(); // error!
    |     ^^^^^^^^^ mutable borrow occurs here
-19 | 
-20 |     println!("the first word is: {}", word);
-   |                                       ---- immutable borrow later used here
+19 |
+20 |     println!("the first word is: {word}");
+   |                                   ---- immutable borrow later used here
 
 For more information about this error, try `rustc --explain E0502`.
 error: could not compile `ownership` due to previous error

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-08-04/src/main.rs

@@ -3,11 +3,11 @@ fn main() {
     let v = vec![1, 2, 3, 4, 5];
 
     let third: &i32 = &v[2];
-    println!("The third element is {}", third);
+    println!("The third element is {third}");
 
     let third: Option<&i32> = v.get(2);
     match third {
-        Some(third) => println!("The third element is {}", third),
+        Some(third) => println!("The third element is {third}"),
         None => println!("There is no third element."),
     }
     // ANCHOR_END: here

listings/ch08-common-collections/listing-08-06/output.txt

@@ -5,12 +5,12 @@ error[E0502]: cannot borrow `v` as mutable because it is also borrowed as immuta
   |
 4 |     let first = &v[0];
   |                  - immutable borrow occurs here
-5 | 
+5 |
 6 |     v.push(6);
   |     ^^^^^^^^^ mutable borrow occurs here
-7 | 
-8 |     println!("The first element is: {}", first);
-  |                                          ----- immutable borrow later used here
+7 |
+8 |     println!("The first element is: {first}");
+  |                                      ----- immutable borrow later used here
 
 For more information about this error, try `rustc --explain E0502`.
 error: could not compile `collections` due to previous error

listings/ch08-common-collections/listing-08-06/src/main.rs

@@ -6,6 +6,6 @@ fn main() {
 
     v.push(6);
 
-    println!("The first element is: {}", first);
+    println!("The first element is: {first}");
     // ANCHOR_END: here
 }

listings/ch08-common-collections/listing-08-07/src/main.rs

@@ -2,7 +2,7 @@ fn main() {
     // ANCHOR: here
     let v = vec![100, 32, 57];
     for i in &v {
-        println!("{}", i);
+        println!("{i}");
     }
     // ANCHOR_END: here
 }

listings/ch08-common-collections/listing-08-16/src/main.rs

@@ -3,6 +3,6 @@ fn main() {
     let mut s1 = String::from("foo");
     let s2 = "bar";
     s1.push_str(s2);
-    println!("s2 is {}", s2);
+    println!("s2 is {s2}");
     // 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/ch08-common-collections/no-listing-03-iterate-over-hashmap/src/main.rs

@@ -8,7 +8,7 @@ fn main() {
     scores.insert(String::from("Yellow"), 50);
 
     for (key, value) in &scores {
-        println!("{}: {}", key, value);
+        println!("{key}: {value}");
     }
     // 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/ch09-error-handling/listing-09-13/src/main.rs

@@ -10,7 +10,7 @@ pub struct Guess {
 impl Guess {
     pub fn new(value: i32) -> Guess {
         if value < 1 || value > 100 {
-            panic!("Guess value must be between 1 and 100, got {}.", value);
+            panic!("Guess value must be between 1 and 100, got {value}.");
         }
 
         Guess { value }

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}");
 }