Update to Rust 1.66.1

.github/workflows/main.yml

@@ -12,8 +12,8 @@ jobs:
     - name: Install Rust
       run: |
         rustup set profile minimal
-        rustup toolchain install 1.65 -c rust-docs
-        rustup default 1.65
+        rustup toolchain install 1.66 -c rust-docs
+        rustup default 1.66
     - name: Install mdbook
       run: |
         mkdir bin

listings/ch02-guessing-game-tutorial/no-listing-02-without-expect/output.txt

@@ -6,8 +6,8 @@ warning: unused `Result` that must be used
 10 |     io::stdin().read_line(&mut guess);
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = note: `#[warn(unused_must_use)]` on by default
    = note: this `Result` may be an `Err` variant, which should be handled
+   = note: `#[warn(unused_must_use)]` on by default
 
 warning: `guessing_game` (bin "guessing_game") generated 1 warning
     Finished dev [unoptimized + debuginfo] target(s) in 0.59s

listings/ch03-common-programming-concepts/no-listing-23-statements-dont-return-values/output.txt

@@ -8,7 +8,7 @@ error[E0308]: mismatched types
   |    |
   |    implicitly returns `()` as its body has no tail or `return` expression
 8 |     x + 1;
-  |          - help: remove this semicolon
+  |          - help: remove this semicolon to return this value
 
 For more information about this error, try `rustc --explain E0308`.
 error: could not compile `functions` due to previous error

listings/ch12-an-io-project/listing-12-12/output.txt

@@ -6,8 +6,8 @@ warning: unused `Result` that must be used
 19 |     run(config);
    |     ^^^^^^^^^^^^
    |
-   = note: `#[warn(unused_must_use)]` on by default
    = note: this `Result` may be an `Err` variant, which should be handled
+   = note: `#[warn(unused_must_use)]` on by default
 
 warning: `minigrep` (bin "minigrep") generated 1 warning
     Finished dev [unoptimized + debuginfo] target(s) in 0.71s

listings/ch13-functional-features/listing-13-14/output.txt

@@ -6,8 +6,8 @@ warning: unused `Map` that must be used
 4 |     v1.iter().map(|x| x + 1);
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
   |
-  = note: `#[warn(unused_must_use)]` on by default
   = note: iterators are lazy and do nothing unless consumed
+  = note: `#[warn(unused_must_use)]` on by default
 
 warning: `iterators` (bin "iterators") generated 1 warning
     Finished dev [unoptimized + debuginfo] target(s) in 0.47s

listings/ch15-smart-pointers/listing-15-03/output.txt

@@ -4,11 +4,11 @@ error[E0072]: recursive type `List` has infinite size
  --> src/main.rs:1:1
   |
 1 | enum List {
-  | ^^^^^^^^^ recursive type has infinite size
+  | ^^^^^^^^^
 2 |     Cons(i32, List),
   |               ---- recursive without indirection
   |
-help: insert some indirection (e.g., a `Box`, `Rc`, or `&`) to make `List` representable
+help: insert some indirection (e.g., a `Box`, `Rc`, or `&`) to break the cycle
   |
 2 |     Cons(i32, Box<List>),
   |               ++++    +

listings/ch18-patterns-and-matching/listing-18-08/output.txt

@@ -14,6 +14,10 @@ help: you might want to use `if let` to ignore the variant that isn't matched
   |
 3 |     let x = if let Some(x) = some_option_value { x } else { todo!() };
   |     ++++++++++                                 ++++++++++++++++++++++
+help: alternatively, you might want to use let else to handle the variant that isn't matched
+  |
+3 |     let Some(x) = some_option_value else { todo!() };
+  |                                     ++++++++++++++++
 
 For more information about this error, try `rustc --explain E0005`.
 error: could not compile `patterns` due to previous error

listings/ch18-patterns-and-matching/listing-18-10/output.txt

@@ -6,9 +6,9 @@ warning: irrefutable `if let` pattern
 2 |     if let x = 5 {
   |        ^^^^^^^^^
   |
-  = note: `#[warn(irrefutable_let_patterns)]` on by default
   = note: this pattern will always match, so the `if let` is useless
   = help: consider replacing the `if let` with a `let`
+  = note: `#[warn(irrefutable_let_patterns)]` on by default
 
 warning: `patterns` (bin "patterns") generated 1 warning
     Finished dev [unoptimized + debuginfo] target(s) in 0.39s

listings/ch19-advanced-features/listing-19-20/output.txt

@@ -11,8 +11,8 @@ error[E0790]: cannot call associated function on trait without specifying the co
    |
 help: use the fully-qualified path to the only available implementation
    |
-20 |     println!("A baby dog is called a {}", <::Dog as Animal>::baby_name());
-   |                                           +++++++++       +
+20 |     println!("A baby dog is called a {}", <Dog as Animal>::baby_name());
+   |                                           +++++++       +
 
 For more information about this error, try `rustc --explain E0790`.
 error: could not compile `traits-example` due to previous error

rust-toolchain

@@ -1 +1 @@
-1.65
+1.66

src/title-page.md

@@ -2,7 +2,7 @@
 
 *by Steve Klabnik and Carol Nichols, with contributions from the Rust Community*
 
-This version of the text assumes you’re using Rust 1.65 (released 2022-11-03)
+This version of the text assumes you’re using Rust 1.66.1 (released 2023-01-10)
 or later. See the [“Installation” section of Chapter 1][install]<!-- ignore -->
 to install or update Rust.