[INFO] cloning repository https://github.com/Rosteelton/rust-book-study
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Rosteelton/rust-book-study" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FRosteelton%2Frust-book-study", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FRosteelton%2Frust-book-study'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] c79578eeceabf6bd437f925387471b51900067c3
[INFO] checking Rosteelton/rust-book-study/c79578eeceabf6bd437f925387471b51900067c3 against master#ab869e094a907cc5d19b4080f22eccaf347f1f95 for pr-129604
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FRosteelton%2Frust-book-study" "/workspace/builds/worker-3-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Rosteelton/rust-book-study on toolchain ab869e094a907cc5d19b4080f22eccaf347f1f95
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Rosteelton/rust-book-study
[INFO] finished tweaking git repo https://github.com/Rosteelton/rust-book-study
[INFO] tweaked toml for git repo https://github.com/Rosteelton/rust-book-study written to /workspace/builds/worker-3-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/Rosteelton/rust-book-study already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: profiles for the non root package will be ignored, specify profiles at the workspace root:
[INFO] [stderr] package:   /workspace/builds/worker-3-tc1/source/chapters/Cargo.toml
[INFO] [stderr] workspace: /workspace/builds/worker-3-tc1/source/Cargo.toml
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded rand_core v0.9.0-alpha.1
[INFO] [stderr]   Downloaded rand v0.9.0-alpha.1
[INFO] [stderr]   Downloaded rand_chacha v0.9.0-alpha.1
[INFO] [stderr]   Downloaded zerocopy-derive v0.8.0-alpha.6
[INFO] [stderr]   Downloaded zerocopy v0.8.0-alpha.6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 85bbe071c01ce39908d72c4ab451fab932504c206edc172d4601fc6310ac5d05
[INFO] running `Command { std: "docker" "start" "-a" "85bbe071c01ce39908d72c4ab451fab932504c206edc172d4601fc6310ac5d05", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "85bbe071c01ce39908d72c4ab451fab932504c206edc172d4601fc6310ac5d05", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "85bbe071c01ce39908d72c4ab451fab932504c206edc172d4601fc6310ac5d05", kill_on_drop: false }`
[INFO] [stdout] 85bbe071c01ce39908d72c4ab451fab932504c206edc172d4601fc6310ac5d05
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f7d1c85f99c3f21b1d5c9db483f56d846512f382f4870942ddd7d3b7deade528
[INFO] running `Command { std: "docker" "start" "-a" "f7d1c85f99c3f21b1d5c9db483f56d846512f382f4870942ddd7d3b7deade528", kill_on_drop: false }`
[INFO] [stderr] warning: profiles for the non root package will be ignored, specify profiles at the workspace root:
[INFO] [stderr] package:   /opt/rustwide/workdir/chapters/Cargo.toml
[INFO] [stderr] workspace: /opt/rustwide/workdir/Cargo.toml
[INFO] [stderr]    Compiling libc v0.2.155
[INFO] [stderr]    Compiling zerocopy v0.8.0-alpha.6
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]     Checking ppv-lite86 v0.2.17
[INFO] [stderr]    Compiling proc-macro2 v1.0.85
[INFO] [stderr]    Compiling unicode-ident v1.0.12
[INFO] [stderr]    Compiling autocfg v1.3.0
[INFO] [stderr]     Checking futures-core v0.3.30
[INFO] [stderr]     Checking futures-sink v0.3.30
[INFO] [stderr]     Checking futures-task v0.3.30
[INFO] [stderr]     Checking memchr v2.7.4
[INFO] [stderr]     Checking pin-utils v0.1.0
[INFO] [stderr]     Checking futures-io v0.3.30
[INFO] [stderr]     Checking pin-project-lite v0.2.14
[INFO] [stderr]     Checking mini_grep v0.1.0 (/opt/rustwide/workdir/mini_grep)
[INFO] [stderr]     Checking oop_state_pattern v0.1.0 (/opt/rustwide/workdir/oop_state_pattern)
[INFO] [stderr]     Checking futures-channel v0.3.30
[INFO] [stderr]    Compiling slab v0.4.9
[INFO] [stderr]    Compiling quote v1.0.36
[INFO] [stderr]    Compiling syn v2.0.66
[INFO] [stderr]     Checking getrandom v0.2.15
[INFO] [stderr]     Checking num_cpus v1.16.0
[INFO] [stderr]     Checking rand_core v0.9.0-alpha.1
[INFO] [stderr]     Checking rand_chacha v0.9.0-alpha.1
[INFO] [stderr]     Checking rand v0.9.0-alpha.1
[INFO] [stderr]     Checking chapters v0.1.0 (/opt/rustwide/workdir/chapters)
[INFO] [stdout] warning: unused variable: `s2`
[INFO] [stdout]  --> chapters/src/bin/chapter_4_borrowing.rs:5:9
[INFO] [stdout]   |
[INFO] [stdout] 5 |     let s2 = s1;
[INFO] [stdout]   |         ^^ help: if this is intentional, prefix it with an underscore: `_s2`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a2`
[INFO] [stdout]   --> chapters/src/bin/chapter_4_borrowing.rs:34:9
[INFO] [stdout]    |
[INFO] [stdout] 34 |     let a2 = get_ownership_2(a1); //a1 is not usable anymore
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_a2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b2`
[INFO] [stdout]   --> chapters/src/bin/chapter_4_borrowing.rs:47:9
[INFO] [stdout]    |
[INFO] [stdout] 47 |     let b2 = work_with_value(&b1); //BORROWING - we borrow value for the function work
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_b2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]   --> chapters/src/bin/chapter_4_borrowing.rs:88:9
[INFO] [stdout]    |
[INFO] [stdout] 88 |     let s: &str = "Hello, world!"; //&str = slice for String - immutable reference
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `slice`
[INFO] [stdout]   --> chapters/src/bin/chapter_4_borrowing.rs:92:9
[INFO] [stdout]    |
[INFO] [stdout] 92 |     let slice = &a[1..3];
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_slice`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]   --> chapters/src/bin/chapter_10_1_lifetime.rs:21:9
[INFO] [stdout]    |
[INFO] [stdout] 21 |     let s: &'static str = "I have a static lifetime.";
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `item1`
[INFO] [stdout]   --> chapters/src/bin/chapter_10_generics.rs:22:18
[INFO] [stdout]    |
[INFO] [stdout] 22 | pub fn some_func(item1: &impl PartialOrd) {}
[INFO] [stdout]    |                  ^^^^^ help: if this is intentional, prefix it with an underscore: `_item1`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b1`
[INFO] [stdout]   --> chapters/src/bin/chapter_8_collections.rs:10:9
[INFO] [stdout]    |
[INFO] [stdout] 10 |     let b1 = b.get(2);
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_b1`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]   --> chapters/src/bin/chapter_10_generics.rs:30:24
[INFO] [stdout]    |
[INFO] [stdout] 30 | fn some_function<T, U>(t: &T, u: &U) -> i32
[INFO] [stdout]    |                        ^ help: if this is intentional, prefix it with an underscore: `_t`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b2`
[INFO] [stdout]   --> chapters/src/bin/chapter_8_collections.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |     let b2 = b[2];
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_b2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `u`
[INFO] [stdout]   --> chapters/src/bin/chapter_10_generics.rs:30:31
[INFO] [stdout]    |
[INFO] [stdout] 30 | fn some_function<T, U>(t: &T, u: &U) -> i32
[INFO] [stdout]    |                               ^ help: if this is intentional, prefix it with an underscore: `_u`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> chapters/src/bin/chapter_3_basics.rs:21:9
[INFO] [stdout]    |
[INFO] [stdout] 21 |     let x = 1_000_000;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> chapters/src/bin/chapter_3_basics.rs:22:9
[INFO] [stdout]    |
[INFO] [stdout] 22 |     let x = 57u8;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> chapters/src/bin/chapter_3_basics.rs:23:9
[INFO] [stdout]    |
[INFO] [stdout] 23 |     let x = 59.123;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `some_function` is never used
[INFO] [stdout]   --> chapters/src/bin/chapter_10_generics.rs:30:4
[INFO] [stdout]    |
[INFO] [stdout] 30 | fn some_function<T, U>(t: &T, u: &U) -> i32
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> chapters/src/bin/chapter_3_basics.rs:27:10
[INFO] [stdout]    |
[INFO] [stdout] 27 |     let (a, b, c, d) = tup;
[INFO] [stdout]    |          ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> chapters/src/bin/chapter_3_basics.rs:27:13
[INFO] [stdout]    |
[INFO] [stdout] 27 |     let (a, b, c, d) = tup;
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]   --> chapters/src/bin/chapter_3_basics.rs:27:16
[INFO] [stdout]    |
[INFO] [stdout] 27 |     let (a, b, c, d) = tup;
[INFO] [stdout]    |                ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `d`
[INFO] [stdout]   --> chapters/src/bin/chapter_3_basics.rs:27:19
[INFO] [stdout]    |
[INFO] [stdout] 27 |     let (a, b, c, d) = tup;
[INFO] [stdout]    |                   ^ help: if this is intentional, prefix it with an underscore: `_d`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> chapters/src/bin/chapter_3_basics.rs:37:9
[INFO] [stdout]    |
[INFO] [stdout] 37 |     let x = [3; 5];
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `run_draw` is never used
[INFO] [stdout]   --> chapters/src/bin/chapter_17_oop.rs:18:8
[INFO] [stdout]    |
[INFO] [stdout] 17 | impl Screen {
[INFO] [stdout]    | ----------- method in this implementation
[INFO] [stdout] 18 |     fn run_draw(&self) {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `x` and `y` are never read
[INFO] [stdout]   --> chapters/src/bin/chapter_17_oop.rs:26:5
[INFO] [stdout]    |
[INFO] [stdout] 25 | pub struct Point {
[INFO] [stdout]    |            ----- fields in this struct
[INFO] [stdout] 26 |     x: u32,
[INFO] [stdout]    |     ^
[INFO] [stdout] 27 |     y: u32,
[INFO] [stdout]    |     ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `place_holder` is never read
[INFO] [stdout]   --> chapters/src/bin/chapter_17_oop.rs:31:5
[INFO] [stdout]    |
[INFO] [stdout] 30 | pub struct Button {
[INFO] [stdout]    |            ------ field in this struct
[INFO] [stdout] 31 |     place_holder: String,
[INFO] [stdout]    |     ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant `TWO_DAYS_SECOND` is never used
[INFO] [stdout]  --> chapters/src/bin/chapter_3_basics.rs:8:11
[INFO] [stdout]   |
[INFO] [stdout] 8 |     const TWO_DAYS_SECOND: u32 = 2 * 24 * 60 * 60;
[INFO] [stdout]   |           ^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s2`
[INFO] [stdout]  --> chapters/src/bin/chapter_4_borrowing.rs:5:9
[INFO] [stdout]   |
[INFO] [stdout] 5 |     let s2 = s1;
[INFO] [stdout]   |         ^^ help: if this is intentional, prefix it with an underscore: `_s2`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a2`
[INFO] [stdout]   --> chapters/src/bin/chapter_4_borrowing.rs:34:9
[INFO] [stdout]    |
[INFO] [stdout] 34 |     let a2 = get_ownership_2(a1); //a1 is not usable anymore
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_a2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b2`
[INFO] [stdout]   --> chapters/src/bin/chapter_4_borrowing.rs:47:9
[INFO] [stdout]    |
[INFO] [stdout] 47 |     let b2 = work_with_value(&b1); //BORROWING - we borrow value for the function work
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_b2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]   --> chapters/src/bin/chapter_4_borrowing.rs:88:9
[INFO] [stdout]    |
[INFO] [stdout] 88 |     let s: &str = "Hello, world!"; //&str = slice for String - immutable reference
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `slice`
[INFO] [stdout]   --> chapters/src/bin/chapter_4_borrowing.rs:92:9
[INFO] [stdout]    |
[INFO] [stdout] 92 |     let slice = &a[1..3];
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_slice`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 9 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `get_ownership` is never used
[INFO] [stdout]   --> chapters/src/bin/chapter_4_borrowing.rs:21:8
[INFO] [stdout]    |
[INFO] [stdout] 21 |     fn get_ownership(x: String) {
[INFO] [stdout]    |        ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]  --> chapters/src/bin/chapter_18_matching.rs:8:20
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let Point { x: x, y: y } = p; //ex: 1
[INFO] [stdout]   |                    ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]  --> chapters/src/bin/chapter_18_matching.rs:8:26
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let Point { x: x, y: y } = p; //ex: 1
[INFO] [stdout]   |                          ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]  --> chapters/src/bin/chapter_18_matching.rs:9:17
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let Point { x, y } = p; //ex: 2
[INFO] [stdout]   |                 ^ help: try ignoring the field: `x: _`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]  --> chapters/src/bin/chapter_18_matching.rs:9:20
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let Point { x, y } = p; //ex: 2
[INFO] [stdout]   |                    ^ help: try ignoring the field: `y: _`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the `x:` in this pattern is redundant
[INFO] [stdout]  --> chapters/src/bin/chapter_18_matching.rs:8:17
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let Point { x: x, y: y } = p; //ex: 1
[INFO] [stdout]   |                 ^^^^ help: use shorthand field pattern: `x`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(non_shorthand_field_patterns)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the `y:` in this pattern is redundant
[INFO] [stdout]  --> chapters/src/bin/chapter_18_matching.rs:8:23
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let Point { x: x, y: y } = p; //ex: 1
[INFO] [stdout]   |                       ^^^^ help: use shorthand field pattern: `y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `split_at_mut` is never used
[INFO] [stdout]   --> chapters/src/bin/chapter_19_super_features.rs:23:8
[INFO] [stdout]    |
[INFO] [stdout] 23 |     fn split_at_mut(values: &mut [i32], mid: usize) -> (&mut [i32], &mut [i32]) {
[INFO] [stdout]    |        ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> chapters/src/bin/chapter_15_rc.rs:43:9
[INFO] [stdout]    |
[INFO] [stdout] 43 |     let b = Cons(3, Rc::clone(&a)); //only increase reference counter, not a deep copy
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `associated_types` is never used
[INFO] [stdout]   --> chapters/src/bin/chapter_19_super_features.rs:53:4
[INFO] [stdout]    |
[INFO] [stdout] 53 | fn associated_types() {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `trait_ex` is never used
[INFO] [stdout]   --> chapters/src/bin/chapter_19_super_features.rs:66:4
[INFO] [stdout]    |
[INFO] [stdout] 66 | fn trait_ex() {
[INFO] [stdout]    |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]   --> chapters/src/bin/chapter_15_rc.rs:44:9
[INFO] [stdout]    |
[INFO] [stdout] 44 |     let c = Cons(4, Rc::clone(&a));
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]   --> chapters/src/bin/chapter_15_rc.rs:17:10
[INFO] [stdout]    |
[INFO] [stdout] 17 |     Cons(i32, Rc<List>),
[INFO] [stdout]    |     ---- ^^^  ^^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     fields in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `List` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]    |
[INFO] [stdout] 17 |     Cons((), ()),
[INFO] [stdout]    |          ~~  ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `split_at_mut` is never used
[INFO] [stdout]   --> chapters/src/bin/chapter_19_super_features.rs:23:8
[INFO] [stdout]    |
[INFO] [stdout] 23 |     fn split_at_mut(values: &mut [i32], mid: usize) -> (&mut [i32], &mut [i32]) {
[INFO] [stdout]    |        ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `associated_types` is never used
[INFO] [stdout]   --> chapters/src/bin/chapter_19_super_features.rs:53:4
[INFO] [stdout]    |
[INFO] [stdout] 53 | fn associated_types() {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `trait_ex` is never used
[INFO] [stdout]   --> chapters/src/bin/chapter_19_super_features.rs:66:4
[INFO] [stdout]    |
[INFO] [stdout] 66 | fn trait_ex() {
[INFO] [stdout]    |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `item1`
[INFO] [stdout]   --> chapters/src/bin/chapter_10_generics.rs:22:18
[INFO] [stdout]    |
[INFO] [stdout] 22 | pub fn some_func(item1: &impl PartialOrd) {}
[INFO] [stdout]    |                  ^^^^^ help: if this is intentional, prefix it with an underscore: `_item1`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]   --> chapters/src/bin/chapter_10_generics.rs:30:24
[INFO] [stdout]    |
[INFO] [stdout] 30 | fn some_function<T, U>(t: &T, u: &U) -> i32
[INFO] [stdout]    |                        ^ help: if this is intentional, prefix it with an underscore: `_t`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `u`
[INFO] [stdout]   --> chapters/src/bin/chapter_10_generics.rs:30:31
[INFO] [stdout]    |
[INFO] [stdout] 30 | fn some_function<T, U>(t: &T, u: &U) -> i32
[INFO] [stdout]    |                               ^ help: if this is intentional, prefix it with an underscore: `_u`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `some_function` is never used
[INFO] [stdout]   --> chapters/src/bin/chapter_10_generics.rs:30:4
[INFO] [stdout]    |
[INFO] [stdout] 30 | fn some_function<T, U>(t: &T, u: &U) -> i32
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]   --> chapters/src/bin/chapter_10_1_lifetime.rs:21:9
[INFO] [stdout]    |
[INFO] [stdout] 21 |     let s: &'static str = "I have a static lifetime.";
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `longest_with_an_announcement` is never used
[INFO] [stdout]   --> chapters/src/bin/chapter_10_1_lifetime.rs:25:8
[INFO] [stdout]    |
[INFO] [stdout] 25 |     fn longest_with_an_announcement<'a, T>(
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Color` is never constructed
[INFO] [stdout]  --> chapters/src/bin/chapter_5_struct.rs:3:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | struct Color(i32, i32, i32); //named tuple
[INFO] [stdout]   |        ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `NoField` is never constructed
[INFO] [stdout]  --> chapters/src/bin/chapter_5_struct.rs:5:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | struct NoField;
[INFO] [stdout]   |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `name` and `is_active` are never read
[INFO] [stdout]   --> chapters/src/bin/chapter_5_struct.rs:9:5
[INFO] [stdout]    |
[INFO] [stdout] 8  | struct User {
[INFO] [stdout]    |        ---- fields in this struct
[INFO] [stdout] 9  |     name: String,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 10 |     age: u32,
[INFO] [stdout] 11 |     is_active: bool,
[INFO] [stdout]    |     ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `User` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::rc::Rc`
[INFO] [stdout]  --> chapters/src/bin/chapter_15_box.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::rc::Rc;
[INFO] [stdout]   |     ^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]   --> chapters/src/bin/chapter_15_box.rs:19:10
[INFO] [stdout]    |
[INFO] [stdout] 19 |     Cons(i32, Box<List>),
[INFO] [stdout]    |     ---- ^^^  ^^^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     fields in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `List` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]    |
[INFO] [stdout] 19 |     Cons((), ()),
[INFO] [stdout]    |          ~~  ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::fs`
[INFO] [stdout]  --> chapters/src/bin/chapter_9_error.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::fs;
[INFO] [stdout]   |     ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `file`
[INFO] [stdout]  --> chapters/src/bin/chapter_9_error.rs:8:9
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let file = File::open("text.txt").unwrap_or_else(|error| {
[INFO] [stdout]   |         ^^^^ help: if this is intentional, prefix it with an underscore: `_file`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `run_draw` is never used
[INFO] [stdout]   --> chapters/src/bin/chapter_17_oop.rs:18:8
[INFO] [stdout]    |
[INFO] [stdout] 17 | impl Screen {
[INFO] [stdout]    | ----------- method in this implementation
[INFO] [stdout] 18 |     fn run_draw(&self) {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `x` and `y` are never read
[INFO] [stdout]   --> chapters/src/bin/chapter_17_oop.rs:26:5
[INFO] [stdout]    |
[INFO] [stdout] 25 | pub struct Point {
[INFO] [stdout]    |            ----- fields in this struct
[INFO] [stdout] 26 |     x: u32,
[INFO] [stdout]    |     ^
[INFO] [stdout] 27 |     y: u32,
[INFO] [stdout]    |     ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `place_holder` is never read
[INFO] [stdout]   --> chapters/src/bin/chapter_17_oop.rs:31:5
[INFO] [stdout]    |
[INFO] [stdout] 30 | pub struct Button {
[INFO] [stdout]    |            ------ field in this struct
[INFO] [stdout] 31 |     place_holder: String,
[INFO] [stdout]    |     ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::rc::Rc`
[INFO] [stdout]  --> chapters/src/bin/chapter_15_box.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::rc::Rc;
[INFO] [stdout]   |     ^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> chapters/src/bin/chapter_15_rc.rs:43:9
[INFO] [stdout]    |
[INFO] [stdout] 43 |     let b = Cons(3, Rc::clone(&a)); //only increase reference counter, not a deep copy
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::fs`
[INFO] [stdout]  --> chapters/src/bin/chapter_9_error.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::fs;
[INFO] [stdout]   |     ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]   --> chapters/src/bin/chapter_15_rc.rs:44:9
[INFO] [stdout]    |
[INFO] [stdout] 44 |     let c = Cons(4, Rc::clone(&a));
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]   --> chapters/src/bin/chapter_15_rc.rs:17:10
[INFO] [stdout]    |
[INFO] [stdout] 17 |     Cons(i32, Rc<List>),
[INFO] [stdout]    |     ---- ^^^  ^^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     fields in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `List` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]    |
[INFO] [stdout] 17 |     Cons((), ()),
[INFO] [stdout]    |          ~~  ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `read_username_from_file` is never used
[INFO] [stdout]   --> chapters/src/bin/chapter_9_error.rs:24:8
[INFO] [stdout]    |
[INFO] [stdout] 24 |     fn read_username_from_file() -> Result<String, Error> {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `file`
[INFO] [stdout]  --> chapters/src/bin/chapter_9_error.rs:8:9
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let file = File::open("text.txt").unwrap_or_else(|error| {
[INFO] [stdout]   |         ^^^^ help: if this is intentional, prefix it with an underscore: `_file`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> chapters/src/bin/chapter_3_basics.rs:21:9
[INFO] [stdout]    |
[INFO] [stdout] 21 |     let x = 1_000_000;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Color` is never constructed
[INFO] [stdout]  --> chapters/src/bin/chapter_5_struct.rs:3:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | struct Color(i32, i32, i32); //named tuple
[INFO] [stdout]   |        ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `NoField` is never constructed
[INFO] [stdout]  --> chapters/src/bin/chapter_5_struct.rs:5:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | struct NoField;
[INFO] [stdout]   |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `name` and `is_active` are never read
[INFO] [stdout]   --> chapters/src/bin/chapter_5_struct.rs:9:5
[INFO] [stdout]    |
[INFO] [stdout] 8  | struct User {
[INFO] [stdout]    |        ---- fields in this struct
[INFO] [stdout] 9  |     name: String,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 10 |     age: u32,
[INFO] [stdout] 11 |     is_active: bool,
[INFO] [stdout]    |     ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `User` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> chapters/src/bin/chapter_3_basics.rs:22:9
[INFO] [stdout]    |
[INFO] [stdout] 22 |     let x = 57u8;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> chapters/src/bin/chapter_3_basics.rs:23:9
[INFO] [stdout]    |
[INFO] [stdout] 23 |     let x = 59.123;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> chapters/src/bin/chapter_3_basics.rs:27:10
[INFO] [stdout]    |
[INFO] [stdout] 27 |     let (a, b, c, d) = tup;
[INFO] [stdout]    |          ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> chapters/src/bin/chapter_3_basics.rs:27:13
[INFO] [stdout]    |
[INFO] [stdout] 27 |     let (a, b, c, d) = tup;
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]   --> chapters/src/bin/chapter_3_basics.rs:27:16
[INFO] [stdout]    |
[INFO] [stdout] 27 |     let (a, b, c, d) = tup;
[INFO] [stdout]    |                ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `d`
[INFO] [stdout]   --> chapters/src/bin/chapter_3_basics.rs:27:19
[INFO] [stdout]    |
[INFO] [stdout] 27 |     let (a, b, c, d) = tup;
[INFO] [stdout]    |                   ^ help: if this is intentional, prefix it with an underscore: `_d`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> chapters/src/bin/chapter_3_basics.rs:37:9
[INFO] [stdout]    |
[INFO] [stdout] 37 |     let x = [3; 5];
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]   --> chapters/src/bin/chapter_15_box.rs:19:10
[INFO] [stdout]    |
[INFO] [stdout] 19 |     Cons(i32, Box<List>),
[INFO] [stdout]    |     ---- ^^^  ^^^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     fields in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `List` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]    |
[INFO] [stdout] 19 |     Cons((), ()),
[INFO] [stdout]    |          ~~  ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b1`
[INFO] [stdout]   --> chapters/src/bin/chapter_8_collections.rs:10:9
[INFO] [stdout]    |
[INFO] [stdout] 10 |     let b1 = b.get(2);
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_b1`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b2`
[INFO] [stdout]   --> chapters/src/bin/chapter_8_collections.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |     let b2 = b[2];
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_b2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]  --> chapters/src/bin/chapter_18_matching.rs:8:20
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let Point { x: x, y: y } = p; //ex: 1
[INFO] [stdout]   |                    ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 8 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]  --> chapters/src/bin/chapter_18_matching.rs:8:26
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let Point { x: x, y: y } = p; //ex: 1
[INFO] [stdout]   |                          ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]  --> chapters/src/bin/chapter_18_matching.rs:9:17
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let Point { x, y } = p; //ex: 2
[INFO] [stdout]   |                 ^ help: try ignoring the field: `x: _`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]  --> chapters/src/bin/chapter_18_matching.rs:9:20
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let Point { x, y } = p; //ex: 2
[INFO] [stdout]   |                    ^ help: try ignoring the field: `y: _`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the `x:` in this pattern is redundant
[INFO] [stdout]  --> chapters/src/bin/chapter_18_matching.rs:8:17
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let Point { x: x, y: y } = p; //ex: 1
[INFO] [stdout]   |                 ^^^^ help: use shorthand field pattern: `x`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(non_shorthand_field_patterns)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the `y:` in this pattern is redundant
[INFO] [stdout]  --> chapters/src/bin/chapter_18_matching.rs:8:23
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let Point { x: x, y: y } = p; //ex: 1
[INFO] [stdout]   |                       ^^^^ help: use shorthand field pattern: `y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling futures-macro v0.3.30
[INFO] [stderr]     Checking futures-util v0.3.30
[INFO] [stderr]     Checking futures-executor v0.3.30
[INFO] [stderr]     Checking futures v0.3.30
[INFO] [stderr]     Checking server v0.1.0 (/opt/rustwide/workdir/server)
[INFO] [stdout] warning: field `id` is never read
[INFO] [stdout]   --> server/src/lib.rs:50:5
[INFO] [stdout]    |
[INFO] [stdout] 49 | pub struct Worker {
[INFO] [stdout]    |            ------ field in this struct
[INFO] [stdout] 50 |     id: usize,
[INFO] [stdout]    |     ^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `id` is never read
[INFO] [stdout]   --> server/src/lib.rs:50:5
[INFO] [stdout]    |
[INFO] [stdout] 49 | pub struct Worker {
[INFO] [stdout]    |            ------ field in this struct
[INFO] [stdout] 50 |     id: usize,
[INFO] [stdout]    |     ^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 13.14s
[INFO] running `Command { std: "docker" "inspect" "f7d1c85f99c3f21b1d5c9db483f56d846512f382f4870942ddd7d3b7deade528", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f7d1c85f99c3f21b1d5c9db483f56d846512f382f4870942ddd7d3b7deade528", kill_on_drop: false }`
[INFO] [stdout] f7d1c85f99c3f21b1d5c9db483f56d846512f382f4870942ddd7d3b7deade528