Backport changes to md

Author: carols10cents

nostarch/appendix.md

@@ -543,14 +543,11 @@ The `rustfmt` tool reformats your code according to the community code style.
 Many collaborative projects use `rustfmt` to prevent arguments about which
 style to use when writing Rust: everyone formats their code using the tool.
 
-To install `rustfmt`, enter the following:
-
-```
-$ rustup component add rustfmt
-```
-
-This command gives you `rustfmt` and `cargo-fmt`, similar to how Rust gives you
-both `rustc` and `cargo`. To format any Cargo project, enter the following:
+Rust installations include `rustfmt` by default, so you should already have the
+programs `rustfmt` and `cargo-fmt` on your system. These two commands are
+analogous to `rustc` and `cargo` in that `rustfmt` allows finer-grained control
+and `cargo-fmt` understands conventions of a project that uses Cargo. To format
+any Cargo project, enter the following:
 
 ```
 $ cargo fmt
@@ -562,9 +559,9 @@ on `rustfmt`, see its documentation at *https://github.com/rust-lang/rustfmt*.
 
 ### Fix Your Code with rustfix
 
-The rustfix tool is included with Rust installations and can automatically fix
+The `rustfix` tool is included with Rust installations and can automatically fix
 compiler warnings that have a clear way to correct the problem that’s likely
-what you want. It’s likely you’ve seen compiler warnings before. For example,
+what you want. You’ve probably seen compiler warnings before. For example,
 consider this code:
 
 Filename: src/main.rs
@@ -576,8 +573,8 @@ fn main() {
 }
 ```
 
-Here, we’re defining variable `x` as mutable, but we never actually mutate it.
-Rust warns us about that:
+Here, we’re defining the variable `x` as mutable, but we never actually mutate
+it. Rust warns us about that:
 
 ```
 $ cargo build
@@ -615,21 +612,16 @@ fn main() {
 }
 ```
 
-The `x` variable is now immutable, and the warning no longer appears.
+The variable `x` is now immutable, and the warning no longer appears.
 
 You can also use the `cargo fix` command to transition your code between
 different Rust editions. Editions are covered in Appendix E at *appendix-05-editions.md*.
 
 ### More Lints with Clippy
 
 The Clippy tool is a collection of lints to analyze your code so you can catch
-common mistakes and improve your Rust code.
-
-To install Clippy, enter the following:
-
-```
-$ rustup component add clippy
-```
+common mistakes and improve your Rust code. Clippy is included with standard
+Rust installations.
 
 To run Clippy’s lints on any Cargo project, enter the following:
 
@@ -640,7 +632,7 @@ $ cargo clippy
 For example, say you write a program that uses an approximation of a
 mathematical constant, such as pi, as this program does:
 
-Filename: src/main.rs
+src/main.rs
 
 ```
 fn main() {
@@ -650,6 +642,8 @@ fn main() {
 }
 ```
 
+
+
 Running `cargo clippy` on this project results in this error:
 
 ```
@@ -666,10 +660,11 @@ error: approximate value of `f{32, 64}::consts::PI` found
 
 This error lets you know that Rust already has a more precise `PI` constant
 defined, and that your program would be more correct if you used the constant
-instead. You would then change your code to use the `PI` constant. The
-following code doesn’t result in any errors or warnings from Clippy:
+instead. You would then change your code to use the `PI` constant.
 
-Filename: src/main.rs
+The following code doesn’t result in any errors or warnings from Clippy:
+
+src/main.rs
 
 ```
 fn main() {
@@ -679,19 +674,21 @@ fn main() {
 }
 ```
 
+
+
 For more information on Clippy, see its documentation at *https://github.com/rust-lang/rust-clippy*.
 
 ### IDE Integration Using rust-analyzer
 
-To help IDE integration, the Rust community recommends using
+To help with IDE integration, the Rust community recommends using
 `rust-analyzer`. This tool is a set of
-compiler-centric utilities that speaks the Language Server Protocol, which is a specification for IDEs and programming languages to
+compiler-centric utilities that speak Language Server Protocol, which is a specification for IDEs and programming languages to
 communicate with each other. Different clients can use `rust-analyzer`, such as
 the Rust analyzer plug-in for Visual Studio Code at *https://marketplace.visualstudio.com/items?itemName=rust-lang.rust-analyzer*.
 
 Visit the `rust-analyzer` project’s home page
 for installation instructions, then install the language server support in your
-particular IDE. Your IDE will gain abilities such as autocompletion, jump to
+particular IDE. Your IDE will gain capabilities such as autocompletion, jump to
 definition, and inline errors.
 
 ## Appendix E - Editions

nostarch/appendix_d.md

@@ -20,7 +20,7 @@ style to use when writing Rust: everyone formats their code using the tool.
 
 Rust installations include `rustfmt` by default, so you should already have the
 programs `rustfmt` and `cargo-fmt` on your system. These two commands are
-analagous to `rustc` and `cargo` in that `rustfmt` allows finer-grained control
+analogous to `rustc` and `cargo` in that `rustfmt` allows finer-grained control
 and `cargo-fmt` understands conventions of a project that uses Cargo. To format
 any Cargo project, enter the following:
 
@@ -42,34 +42,30 @@ example, consider this code:
 Filename: src/main.rs
 
 ```
-fn do_something() {}
-
 fn main() {
-    for i in 0..100 {
-        do_something();
-    }
+    let mut x = 42;
+    println!("{x}");
 }
 ```
 
-Here, we’re calling the `do_something` function 100 times, but we never use the
-variable `i` in the body of the `for` loop. Rust warns us about that:
+Here, we’re defining the variable `x` as mutable, but we never actually mutate
+it. Rust warns us about that:
 
 ```
 $ cargo build
    Compiling myprogram v0.1.0 (file:///projects/myprogram)
-warning: unused variable: `i`
- --> src/main.rs:4:9
+warning: variable does not need to be mutable
+ --> src/main.rs:2:9
   |
-4 |     for i in 0..100 {
-  |         ^ help: consider using `_i` instead
+2 |     let mut x = 0;
+  |         ----^
+  |         |
+  |         help: remove this `mut`
   |
-  = note: #[warn(unused_variables)] on by default
-
-    Finished dev [unoptimized + debuginfo] target(s) in 0.50s
+  = note: `#[warn(unused_mut)]` on by default
 ```
 
-The warning suggests that we use `_i` as a name instead: the underscore
-indicates that we intend for this variable to be unused. We can automatically
+The warning suggests that we remove the `mut` keyword. We can automatically
 apply that suggestion using the `rustfix` tool by running the command `cargo
 fix`:
 
@@ -86,16 +82,13 @@ code:
 Filename: src/main.rs
 
 ```
-fn do_something() {}
-
 fn main() {
-    for _i in 0..100 {
-        do_something();
-    }
+    let x = 42;
+    println!("{x}");
 }
 ```
 
-The `for` loop variable is now named `_i`, and the warning no longer appears.
+The variable `x` is now immutable, and the warning no longer appears.
 
 You can also use the `cargo fix` command to transition your code between
 different Rust editions. Editions are covered in Appendix E.
@@ -157,7 +150,7 @@ fn main() {
 ```
 
 For more information on Clippy, see its documentation at
-*https://github.com/rust-lang/rust-clippy**.*
+*https://github.com/rust-lang/rust-clippy*.
 
 ## IDE Integration Using rust-analyzer
 
@@ -171,5 +164,5 @@ languages to communicate with each other. Different clients can use
 Visit the `rust-analyzer` project’s home page at
 *https://rust-analyzer.github.io* for installation instructions, then install
 the language server support in your particular IDE. Your IDE will gain
-capabilities such as autocompletion, jump to definition, and inline errors
+capabilities such as autocompletion, jump to definition, and inline errors.
 

src/appendix-04-useful-development-tools.md

@@ -10,22 +10,12 @@ The `rustfmt` tool reformats your code according to the community code style.
 Many collaborative projects use `rustfmt` to prevent arguments about which
 style to use when writing Rust: everyone formats their code using the tool.
 
-Rust installations include rustfmt by default, so you should already have the
+Rust installations include `rustfmt` by default, so you should already have the
 programs `rustfmt` and `cargo-fmt` on your system. These two commands are
 analogous to `rustc` and `cargo` in that `rustfmt` allows finer-grained control
 and `cargo-fmt` understands conventions of a project that uses Cargo. To format
 any Cargo project, enter the following:
 
-```sh
-$ cargo fmt
-```
-
-Running this command reformats all the Rust code in the current crate. This
-should only change the code style, not the code semantics.
-
-This command gives you `rustfmt` and `cargo-fmt`, similar to how Rust gives you
-both `rustc` and `cargo`. To format any Cargo project, enter the following:
-
 ```console
 $ cargo fmt
 ```
@@ -34,13 +24,11 @@ Running this command reformats all the Rust code in the current crate. This
 should only change the code style, not the code semantics. For more information
 on `rustfmt`, see [its documentation][rustfmt].
 
-[rustfmt]: https://github.com/rust-lang/rustfmt
-
 ### Fix Your Code with `rustfix`
 
 The `rustfix` tool is included with Rust installations and can automatically fix
 compiler warnings that have a clear way to correct the problem that’s likely
-what you want. It’s likely you’ve seen compiler warnings before. For example,
+what you want. You’ve probably seen compiler warnings before. For example,
 consider this code:
 
 <span class="filename">Filename: src/main.rs</span>
@@ -92,7 +80,7 @@ fn main() {
 }
 ```
 
-The `x` variable is now immutable, and the warning no longer appears.
+The variable `x` is now immutable, and the warning no longer appears.
 
 You can also use the `cargo fix` command to transition your code between
 different Rust editions. Editions are covered in [Appendix E][editions].
@@ -140,8 +128,9 @@ error: approximate value of `f{32, 64}::consts::PI` found
 
 This error lets you know that Rust already has a more precise `PI` constant
 defined, and that your program would be more correct if you used the constant
-instead. You would then change your code to use the `PI` constant. The
-following code doesn’t result in any errors or warnings from Clippy:
+instead. You would then change your code to use the `PI` constant.
+
+The following code doesn’t result in any errors or warnings from Clippy:
 
 <Listing file-name="src/main.rs">
 
@@ -157,24 +146,23 @@ fn main() {
 
 For more information on Clippy, see [its documentation][clippy].
 
-[clippy]: https://github.com/rust-lang/rust-clippy
-
 ### IDE Integration Using `rust-analyzer`
 
-To help IDE integration, the Rust community recommends using
+To help with IDE integration, the Rust community recommends using
 [`rust-analyzer`][rust-analyzer]<!-- ignore -->. This tool is a set of
-compiler-centric utilities that speaks the [Language Server Protocol][lsp]<!--
+compiler-centric utilities that speak [Language Server Protocol][lsp]<!--
 ignore -->, which is a specification for IDEs and programming languages to
 communicate with each other. Different clients can use `rust-analyzer`, such as
 [the Rust analyzer plug-in for Visual Studio Code][vscode].
 
-[lsp]: http://langserver.org/
-[vscode]: https://marketplace.visualstudio.com/items?itemName=rust-lang.rust-analyzer
-
 Visit the `rust-analyzer` project’s [home page][rust-analyzer]<!-- ignore -->
 for installation instructions, then install the language server support in your
-particular IDE. Your IDE will gain abilities such as autocompletion, jump to
+particular IDE. Your IDE will gain capabilities such as autocompletion, jump to
 definition, and inline errors.
 
-[rust-analyzer]: https://rust-analyzer.github.io
+[rustfmt]: https://github.com/rust-lang/rustfmt
 [editions]: appendix-05-editions.md
+[clippy]: https://github.com/rust-lang/rust-clippy
+[rust-analyzer]: https://rust-analyzer.github.io
+[lsp]: http://langserver.org/
+[vscode]: https://marketplace.visualstudio.com/items?itemName=rust-lang.rust-analyzer