[INFO] cloning repository https://github.com/marvinang/learn_rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/marvinang/learn_rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmarvinang%2Flearn_rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmarvinang%2Flearn_rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 6953aef0fb9b8c86912a18f86ab2e1dec32f625f
[INFO] checking marvinang/learn_rust against try#8de4b308b608cded0ebccf658a0fc719bce87d4e for pr-89056
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmarvinang%2Flearn_rust" "/workspace/builds/worker-104/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-104/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/marvinang/learn_rust on toolchain 8de4b308b608cded0ebccf658a0fc719bce87d4e
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8de4b308b608cded0ebccf658a0fc719bce87d4e" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/marvinang/learn_rust
[INFO] finished tweaking git repo https://github.com/marvinang/learn_rust
[INFO] tweaked toml for git repo https://github.com/marvinang/learn_rust written to /workspace/builds/worker-104/source/Cargo.toml
[INFO] crate git repo https://github.com/marvinang/learn_rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8de4b308b608cded0ebccf658a0fc719bce87d4e" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-104/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-104/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+8de4b308b608cded0ebccf658a0fc719bce87d4e" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e35eafda50ec5f5b2a3935637c0a7319b1b6574b22bcd67dd7cee71597810091
[INFO] running `Command { std: "docker" "start" "-a" "e35eafda50ec5f5b2a3935637c0a7319b1b6574b22bcd67dd7cee71597810091", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e35eafda50ec5f5b2a3935637c0a7319b1b6574b22bcd67dd7cee71597810091", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e35eafda50ec5f5b2a3935637c0a7319b1b6574b22bcd67dd7cee71597810091", kill_on_drop: false }`
[INFO] [stdout] e35eafda50ec5f5b2a3935637c0a7319b1b6574b22bcd67dd7cee71597810091
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-104/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-104/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" "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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+8de4b308b608cded0ebccf658a0fc719bce87d4e" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0e802ad875ff5e47c0f3fd0f11b781c9d191c6434131f593a4c0bde933ad236c
[INFO] running `Command { std: "docker" "start" "-a" "0e802ad875ff5e47c0f3fd0f11b781c9d191c6434131f593a4c0bde933ad236c", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling proc-macro2 v1.0.29
[INFO] [stderr]    Compiling libc v0.2.71
[INFO] [stderr]    Compiling syn v1.0.76
[INFO] [stderr]     Checking rand_core v0.4.2
[INFO] [stderr]    Compiling unicode-xid v0.2.2
[INFO] [stderr]     Checking a11_tests v0.1.0 (/opt/rustwide/workdir/a11_tests)
[INFO] [stderr]     Checking a12_command_line v0.1.0 (/opt/rustwide/workdir/a12_command_line)
[INFO] [stderr]     Checking a20_webserver v0.1.0 (/opt/rustwide/workdir/a20_webserver)
[INFO] [stderr]     Checking hello_macro v0.1.0 (/opt/rustwide/workdir/hello_macro)
[INFO] [stderr]     Checking a17_oop v0.1.0 (/opt/rustwide/workdir/a17_oop)
[INFO] [stderr]     Checking a3_common_concepts v0.1.0 (/opt/rustwide/workdir/a3_common_concepts)
[INFO] [stderr]     Checking a8_common_collections v0.1.0 (/opt/rustwide/workdir/a8_common_collections)
[INFO] [stderr]     Checking a15_pointers v0.1.0 (/opt/rustwide/workdir/a15_pointers)
[INFO] [stderr]     Checking a14_cargo_crates v0.1.0 (/opt/rustwide/workdir/a14_cargo_crates)
[INFO] [stderr]     Checking a10_generic_traits_lifetime v0.1.0 (/opt/rustwide/workdir/a10_generic_traits_lifetime)
[INFO] [stderr]     Checking a5_structs v0.1.0 (/opt/rustwide/workdir/a5_structs)
[INFO] [stderr]     Checking a4_ownership v0.1.0 (/opt/rustwide/workdir/a4_ownership)
[INFO] [stderr]     Checking a21_appendix v0.1.0 (/opt/rustwide/workdir/a21_appendix)
[INFO] [stderr]     Checking a16_concurrency v0.1.0 (/opt/rustwide/workdir/a16_concurrency)
[INFO] [stderr]     Checking a6_enums_match v0.1.0 (/opt/rustwide/workdir/a6_enums_match)
[INFO] [stderr]     Checking a18_patterns_matching v0.1.0 (/opt/rustwide/workdir/a18_patterns_matching)
[INFO] [stderr]     Checking a1_started v0.1.0 (/opt/rustwide/workdir/a1_started)
[INFO] [stderr]     Checking a9_error v0.1.0 (/opt/rustwide/workdir/a9_error)
[INFO] [stderr]     Checking a13_functional v0.1.0 (/opt/rustwide/workdir/a13_functional)
[INFO] [stdout] warning: type `List_Rc` should have an upper camel case name
[INFO] [stdout]    --> a15_pointers/src/main.rs:297:6
[INFO] [stdout]     |
[INFO] [stdout] 297 | enum List_Rc {
[INFO] [stdout]     |      ^^^^^^^ help: convert the identifier to upper camel case: `ListRc`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(non_camel_case_types)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `post`
[INFO] [stdout]   --> a17_oop/src/blog.rs:59:27
[INFO] [stdout]    |
[INFO] [stdout] 59 |     fn content<'a>(&self, post: &'a Post) -> &'a str {
[INFO] [stdout]    |                           ^^^^ help: if this is intentional, prefix it with an underscore: `_post`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `channel_ownership`
[INFO] [stdout]    --> a16_concurrency/src/main.rs:197:4
[INFO] [stdout]     |
[INFO] [stdout] 197 | fn channel_ownership() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Screen`
[INFO] [stdout]    --> a17_oop/src/main.rs:167:16
[INFO] [stdout]     |
[INFO] [stdout] 167 |     pub struct Screen<T: Draw> {
[INFO] [stdout]     |                ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `run`
[INFO] [stdout]    --> a17_oop/src/main.rs:175:16
[INFO] [stdout]     |
[INFO] [stdout] 175 |         pub fn run(&self) {
[INFO] [stdout]     |                ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Screen`
[INFO] [stdout]    --> a17_oop/src/main.rs:220:16
[INFO] [stdout]     |
[INFO] [stdout] 220 |     pub struct Screen {
[INFO] [stdout]     |                ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `simulated_expensive_calculation`
[INFO] [stdout]   --> a13_functional/src/main.rs:20:4
[INFO] [stdout]    |
[INFO] [stdout] 20 | fn simulated_expensive_calculation(intensity: u32) -> u32 {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `a` is never read
[INFO] [stdout]    --> a3_common_concepts/main.rs:135:13
[INFO] [stdout]     |
[INFO] [stdout] 135 |     let mut a = 123;
[INFO] [stdout]     |             ^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `Iterator_count_std` should have a snake case name
[INFO] [stdout]    --> a13_functional/src/main.rs:357:4
[INFO] [stdout]     |
[INFO] [stdout] 357 | fn Iterator_count_std() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^ help: convert the identifier to snake case (notice the capitalization): `iterator_count_std`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(non_snake_case)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]    --> a3_common_concepts/main.rs:143:9
[INFO] [stdout]     |
[INFO] [stdout] 143 |     let b = 123;
[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 variable: `b`
[INFO] [stdout]    --> a3_common_concepts/main.rs:144:9
[INFO] [stdout]     |
[INFO] [stdout] 144 |     let b = "456";
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]    --> a3_common_concepts/main.rs:155:9
[INFO] [stdout]     |
[INFO] [stdout] 155 |     let y = 2.0; // f64
[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]    --> a3_common_concepts/main.rs:156:9
[INFO] [stdout]     |
[INFO] [stdout] 156 |     let x: f32 = 10.1; //f32
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]    --> a3_common_concepts/main.rs:158:9
[INFO] [stdout]     |
[INFO] [stdout] 158 |     let t = true;
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_t`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]    --> a3_common_concepts/main.rs:159:9
[INFO] [stdout]     |
[INFO] [stdout] 159 |     let f: bool = false;
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]    --> a3_common_concepts/main.rs:161:9
[INFO] [stdout]     |
[INFO] [stdout] 161 |     let c = 'z';
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `z`
[INFO] [stdout]    --> a3_common_concepts/main.rs:162:9
[INFO] [stdout]     |
[INFO] [stdout] 162 |     let z = 'Z';
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_z`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `heart_eyed_cat`
[INFO] [stdout]    --> a3_common_concepts/main.rs:163:9
[INFO] [stdout]     |
[INFO] [stdout] 163 |     let heart_eyed_cat = '😻';
[INFO] [stdout]     |         ^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_heart_eyed_cat`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tup`
[INFO] [stdout]    --> a3_common_concepts/main.rs:165:9
[INFO] [stdout]     |
[INFO] [stdout] 165 |     let tup = (100, 2.5, -80);
[INFO] [stdout]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_tup`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]    --> a3_common_concepts/main.rs:169:10
[INFO] [stdout]     |
[INFO] [stdout] 169 |     let (x, y, z) = tup;
[INFO] [stdout]     |          ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `z`
[INFO] [stdout]    --> a3_common_concepts/main.rs:169:16
[INFO] [stdout]     |
[INFO] [stdout] 169 |     let (x, y, z) = tup;
[INFO] [stdout]     |                ^ help: if this is intentional, prefix it with an underscore: `_z`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t1`
[INFO] [stdout]    --> a3_common_concepts/main.rs:172:9
[INFO] [stdout]     |
[INFO] [stdout] 172 |     let t1 = tup.0;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_t1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t3`
[INFO] [stdout]    --> a3_common_concepts/main.rs:173:9
[INFO] [stdout]     |
[INFO] [stdout] 173 |     let t3 = tup.2;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_t3`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `arr`
[INFO] [stdout]    --> a3_common_concepts/main.rs:175:9
[INFO] [stdout]     |
[INFO] [stdout] 175 |     let arr = [1, 2, 3, 4, 5, 6];
[INFO] [stdout]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_arr`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `months`
[INFO] [stdout]    --> a3_common_concepts/main.rs:176:9
[INFO] [stdout]     |
[INFO] [stdout] 176 |     let months = [
[INFO] [stdout]     |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_months`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `array`
[INFO] [stdout]    --> a3_common_concepts/main.rs:191:9
[INFO] [stdout]     |
[INFO] [stdout] 191 |     let array: [i32; 5] = [1, 2, 3, 4, 10];
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_array`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]    --> a3_common_concepts/main.rs:260:9
[INFO] [stdout]     |
[INFO] [stdout] 260 |     let a = 10; // end line commets
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `lucky_number`
[INFO] [stdout]    --> a3_common_concepts/main.rs:265:9
[INFO] [stdout]     |
[INFO] [stdout] 265 |     let lucky_number = 1;
[INFO] [stdout]     |         ^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_lucky_number`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> a3_common_concepts/main.rs:140:9
[INFO] [stdout]     |
[INFO] [stdout] 140 |     let mut a = 50;
[INFO] [stdout]     |         ----^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant is never used: `MAX_POINT`
[INFO] [stdout]    --> a3_common_concepts/main.rs:146:5
[INFO] [stdout]     |
[INFO] [stdout] 146 |     const MAX_POINT: u32 = 1000_1000;
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]    --> a15_pointers/src/main.rs:247:9
[INFO] [stdout]     |
[INFO] [stdout] 247 |     let c = CustomSmartPointer {
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `d`
[INFO] [stdout]    --> a15_pointers/src/main.rs:250:9
[INFO] [stdout]     |
[INFO] [stdout] 250 |     let d = CustomSmartPointer {
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_d`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]    --> a15_pointers/src/main.rs:312:9
[INFO] [stdout]     |
[INFO] [stdout] 312 |     let b = List_Rc::Cons(3, Rc::clone(&a));
[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]    --> a15_pointers/src/main.rs:313:9
[INFO] [stdout]     |
[INFO] [stdout] 313 |     let c = List_Rc::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: unused variable: `b`
[INFO] [stdout]    --> a15_pointers/src/main.rs:323:9
[INFO] [stdout]     |
[INFO] [stdout] 323 |     let b = List_Rc::Cons(3, Rc::clone(&a));
[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]    --> a15_pointers/src/main.rs:326:13
[INFO] [stdout]     |
[INFO] [stdout] 326 |         let c = List_Rc::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: unused variable: `x`
[INFO] [stdout]    --> a15_pointers/src/main.rs:381:9
[INFO] [stdout]     |
[INFO] [stdout] 381 |     let x = 5;
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `branch`
[INFO] [stdout]    --> a15_pointers/src/main.rs:665:13
[INFO] [stdout]     |
[INFO] [stdout] 665 |         let branch = Rc::new(Node {
[INFO] [stdout]     |             ^^^^^^ help: if this is intentional, prefix it with an underscore: `_branch`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `immutable`
[INFO] [stdout]    --> a15_pointers/src/main.rs:380:4
[INFO] [stdout]     |
[INFO] [stdout] 380 | fn immutable() {
[INFO] [stdout]     |    ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `value`
[INFO] [stdout]    --> a15_pointers/src/main.rs:649:9
[INFO] [stdout]     |
[INFO] [stdout] 649 |         value: i32,
[INFO] [stdout]     |         ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `children`
[INFO] [stdout]    --> a15_pointers/src/main.rs:650:9
[INFO] [stdout]     |
[INFO] [stdout] 650 |         children: RefCell<Vec<Rc<Node>>>,
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `tree`
[INFO] [stdout]    --> a15_pointers/src/main.rs:660:12
[INFO] [stdout]     |
[INFO] [stdout] 660 |     pub fn tree() {
[INFO] [stdout]     |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `value`
[INFO] [stdout]    --> a15_pointers/src/main.rs:687:9
[INFO] [stdout]     |
[INFO] [stdout] 687 |         value: i32,
[INFO] [stdout]     |         ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `children`
[INFO] [stdout]    --> a15_pointers/src/main.rs:689:9
[INFO] [stdout]     |
[INFO] [stdout] 689 |         children: RefCell<Vec<Rc<Node>>>,
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]   --> a8_common_collections/src/main.rs:23:9
[INFO] [stdout]    |
[INFO] [stdout] 23 |     let v: Vec<i32> = Vec::new();
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `does_not_exist`
[INFO] [stdout]   --> a8_common_collections/src/main.rs:60:9
[INFO] [stdout]    |
[INFO] [stdout] 60 |     let does_not_exist = v.get(100);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_does_not_exist`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]   --> a8_common_collections/src/main.rs:74:13
[INFO] [stdout]    |
[INFO] [stdout] 74 |     let mut v = vec![1, 2, 3, 4, 5];
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `str`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:142:9
[INFO] [stdout]     |
[INFO] [stdout] 142 |     let str = String::new();
[INFO] [stdout]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_str`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:147:9
[INFO] [stdout]     |
[INFO] [stdout] 147 |     let s = data.to_string();
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:150:9
[INFO] [stdout]     |
[INFO] [stdout] 150 |     let s = "Initail contents".to_string();
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:156:9
[INFO] [stdout]     |
[INFO] [stdout] 156 |     let hello = String::from("السلام عليكم");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:157:9
[INFO] [stdout]     |
[INFO] [stdout] 157 |     let hello = String::from("Dobrý den");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:158:9
[INFO] [stdout]     |
[INFO] [stdout] 158 |     let hello = String::from("Hello");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:159:9
[INFO] [stdout]     |
[INFO] [stdout] 159 |     let hello = String::from("שָׁלוֹם");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:164:9
[INFO] [stdout]     |
[INFO] [stdout] 164 |     let hello = String::from("안녕하세요");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:169:9
[INFO] [stdout]     |
[INFO] [stdout] 169 |     let hello = String::from("Здравствуйте");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:170:9
[INFO] [stdout]     |
[INFO] [stdout] 170 |     let hello = String::from("Hola");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `one`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:186:9
[INFO] [stdout]     |
[INFO] [stdout] 186 |     let one = 1.to_string();
[INFO] [stdout]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_one`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `float`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:187:9
[INFO] [stdout]     |
[INFO] [stdout] 187 |     let float = 1.3.to_string();
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_float`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `slice`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:188:9
[INFO] [stdout]     |
[INFO] [stdout] 188 |     let slice = "slice".to_string();
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_slice`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `len`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:222:9
[INFO] [stdout]     |
[INFO] [stdout] 222 |     let len = s.len();
[INFO] [stdout]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_len`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `len`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:225:9
[INFO] [stdout]     |
[INFO] [stdout] 225 |     let len = s.chars().count();
[INFO] [stdout]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_len`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:228:9
[INFO] [stdout]     |
[INFO] [stdout] 228 |     let a = s.chars().nth(2);
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `combine`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:264:13
[INFO] [stdout]     |
[INFO] [stdout] 264 |     let mut combine: HashMap<_, _> = teams.iter().zip(scores.iter()).collect();
[INFO] [stdout]     |             ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_combine`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> a8_common_collections/src/main.rs:55:9
[INFO] [stdout]    |
[INFO] [stdout] 55 |     let mut v = vec![1, 2, 3, 4, 5];
[INFO] [stdout]    |         ----^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> a8_common_collections/src/main.rs:74:9
[INFO] [stdout]    |
[INFO] [stdout] 74 |     let mut v = vec![1, 2, 3, 4, 5];
[INFO] [stdout]    |         ----^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> a8_common_collections/src/main.rs:264:9
[INFO] [stdout]     |
[INFO] [stdout] 264 |     let mut combine: HashMap<_, _> = teams.iter().zip(scores.iter()).collect();
[INFO] [stdout]     |         ----^^^^^^^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]   --> a4_ownership/main.rs:35:9
[INFO] [stdout]    |
[INFO] [stdout] 35 |     let s = "runoob"; // 这里是变量 s 的可用范围
[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: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> a4_ownership/main.rs:39:13
[INFO] [stdout]    |
[INFO] [stdout] 39 |         let a = "hello";
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> a4_ownership/main.rs:74:9
[INFO] [stdout]    |
[INFO] [stdout] 74 |     let y = x;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s2`
[INFO] [stdout]   --> a4_ownership/main.rs:78:9
[INFO] [stdout]    |
[INFO] [stdout] 78 |     let s2 = s1;
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_s2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s2`
[INFO] [stdout]    --> a4_ownership/main.rs:100:9
[INFO] [stdout]     |
[INFO] [stdout] 100 |     let s2 = s1;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_s2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s1`
[INFO] [stdout]    --> a4_ownership/main.rs:165:9
[INFO] [stdout]     |
[INFO] [stdout] 165 |     let s1 = gives_ownership(); // gives_ownership 移动它的返回值到 s1
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_s1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c1`
[INFO] [stdout]    --> a14_cargo_crates/src/main.rs:100:16
[INFO] [stdout]     |
[INFO] [stdout] 100 |     pub fn mix(c1: PrimaryColor, c2: PrimaryColor) -> SecondaryColor {
[INFO] [stdout]     |                ^^ help: if this is intentional, prefix it with an underscore: `_c1`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c2`
[INFO] [stdout]    --> a14_cargo_crates/src/main.rs:100:34
[INFO] [stdout]     |
[INFO] [stdout] 100 |     pub fn mix(c1: PrimaryColor, c2: PrimaryColor) -> SecondaryColor {
[INFO] [stdout]     |                                  ^^ help: if this is intentional, prefix it with an underscore: `_c2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s3`
[INFO] [stdout]    --> a4_ownership/main.rs:169:9
[INFO] [stdout]     |
[INFO] [stdout] 169 |     let s3 = takes_and_gives_back(s2); // s2 被当作参数移动, s3 获得返回值所有权
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_s3`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r1`
[INFO] [stdout]    --> a4_ownership/main.rs:217:9
[INFO] [stdout]     |
[INFO] [stdout] 217 |     let r1 = &mut s;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_r1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> a4_ownership/main.rs:233:18
[INFO] [stdout]     |
[INFO] [stdout] 233 | fn cannot_change(s: &String) {
[INFO] [stdout]     |                  ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r1`
[INFO] [stdout]    --> a4_ownership/main.rs:259:13
[INFO] [stdout]     |
[INFO] [stdout] 259 |         let r1 = &mut s;
[INFO] [stdout]     |             ^^ help: if this is intentional, prefix it with an underscore: `_r1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s3`
[INFO] [stdout]    --> a4_ownership/main.rs:261:9
[INFO] [stdout]     |
[INFO] [stdout] 261 |     let s3 = &mut s;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_s3`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s1`
[INFO] [stdout]    --> a4_ownership/main.rs:267:9
[INFO] [stdout]     |
[INFO] [stdout] 267 |     let s1 = &s;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_s1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s2`
[INFO] [stdout]    --> a4_ownership/main.rs:268:9
[INFO] [stdout]     |
[INFO] [stdout] 268 |     let s2 = &s;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_s2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `s2` is never read
[INFO] [stdout]    --> a4_ownership/main.rs:302:13
[INFO] [stdout]     |
[INFO] [stdout] 302 |     let mut s2 = &s1;
[INFO] [stdout]     |             ^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable statement
[INFO] [stdout]   --> a9_error/src/main.rs:46:5
[INFO] [stdout]    |
[INFO] [stdout] 45 |     panic!("error occured");
[INFO] [stdout]    |     ------------------------ any code following this expression is unreachable
[INFO] [stdout] 46 |     println!("Hello, Rust");
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^ unreachable statement
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unreachable_code)]` on by default
[INFO] [stdout]    = note: this warning originates in the macro `println` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c1`
[INFO] [stdout]    --> a14_cargo_crates/src/main.rs:100:16
[INFO] [stdout]     |
[INFO] [stdout] 100 |     pub fn mix(c1: PrimaryColor, c2: PrimaryColor) -> SecondaryColor {
[INFO] [stdout]     |                ^^ help: if this is intentional, prefix it with an underscore: `_c1`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable statement
[INFO] [stdout]   --> a9_error/src/main.rs:46:5
[INFO] [stdout]    |
[INFO] [stdout] 45 |     panic!("error occured");
[INFO] [stdout]    |     ------------------------ any code following this expression is unreachable
[INFO] [stdout] 46 |     println!("Hello, Rust");
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^ unreachable statement
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unreachable_code)]` on by default
[INFO] [stdout]    = note: this warning originates in the macro `println` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c2`
[INFO] [stdout]    --> a14_cargo_crates/src/main.rs:100:34
[INFO] [stdout]     |
[INFO] [stdout] 100 |     pub fn mix(c1: PrimaryColor, c2: PrimaryColor) -> SecondaryColor {
[INFO] [stdout]     |                                  ^^ help: if this is intentional, prefix it with an underscore: `_c2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]   --> a9_error/src/main.rs:81:9
[INFO] [stdout]    |
[INFO] [stdout] 81 |     let f = match f {
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `file`
[INFO] [stdout]    --> a9_error/src/main.rs:116:15
[INFO] [stdout]     |
[INFO] [stdout] 116 |     if let Ok(file) = f {
[INFO] [stdout]     |               ^^^^ help: if this is intentional, prefix it with an underscore: `_file`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f1`
[INFO] [stdout]    --> a9_error/src/main.rs:129:9
[INFO] [stdout]     |
[INFO] [stdout] 129 |     let f1 = File::open("hello.txt").unwrap();
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_f1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f2`
[INFO] [stdout]    --> a9_error/src/main.rs:130:9
[INFO] [stdout]     |
[INFO] [stdout] 130 |     let f2 = File::open("hello.txt").expect("Failed to open.");
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_f2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]    --> a9_error/src/main.rs:235:9
[INFO] [stdout]     |
[INFO] [stdout] 235 |     let f = File::open("hello.txt")?;
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `scope`
[INFO] [stdout]   --> a4_ownership/main.rs:33:4
[INFO] [stdout]    |
[INFO] [stdout] 33 | fn scope() {
[INFO] [stdout]    |    ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `cannot_change`
[INFO] [stdout]    --> a4_ownership/main.rs:233:4
[INFO] [stdout]     |
[INFO] [stdout] 233 | fn cannot_change(s: &String) {
[INFO] [stdout]     |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:111:9
[INFO] [stdout]     |
[INFO] [stdout] 111 |     let a = 6;
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[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: function is never used: `panic_error`
[INFO] [stdout]   --> a9_error/src/main.rs:44:4
[INFO] [stdout]    |
[INFO] [stdout] 44 | fn panic_error() {
[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]    --> a18_patterns_matching/src/main.rs:112:10
[INFO] [stdout]     |
[INFO] [stdout] 112 |     let (x, y, z) = (1, 2, 3);
[INFO] [stdout]     |          ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:112:13
[INFO] [stdout]     |
[INFO] [stdout] 112 |     let (x, y, z) = (1, 2, 3);
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `z`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:112:16
[INFO] [stdout]     |
[INFO] [stdout] 112 |     let (x, y, z) = (1, 2, 3);
[INFO] [stdout]     |                ^ help: if this is intentional, prefix it with an underscore: `_z`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:118:8
[INFO] [stdout]     |
[INFO] [stdout] 118 | fn foo(x: i32) {}
[INFO] [stdout]     |        ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `feet`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:291:11
[INFO] [stdout]     |
[INFO] [stdout] 291 |     let ((feet, inches), Point { x, y }) = ((3, 10), Point { x: 3, y: -10 });
[INFO] [stdout]     |           ^^^^ help: if this is intentional, prefix it with an underscore: `_feet`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `inches`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:291:17
[INFO] [stdout]     |
[INFO] [stdout] 291 |     let ((feet, inches), Point { x, y }) = ((3, 10), Point { x: 3, y: -10 });
[INFO] [stdout]     |                 ^^^^^^ help: if this is intentional, prefix it with an underscore: `_inches`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:291:34
[INFO] [stdout]     |
[INFO] [stdout] 291 |     let ((feet, inches), Point { x, y }) = ((3, 10), Point { x: 3, y: -10 });
[INFO] [stdout]     |                                  ^ help: try ignoring the field: `x: _`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:291:37
[INFO] [stdout]     |
[INFO] [stdout] 291 |     let ((feet, inches), Point { x, y }) = ((3, 10), Point { x: 3, y: -10 });
[INFO] [stdout]     |                                     ^ help: try ignoring the field: `y: _`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:348:9
[INFO] [stdout]     |
[INFO] [stdout] 348 |     let y = 10;
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]   --> a9_error/src/main.rs:81:9
[INFO] [stdout]    |
[INFO] [stdout] 81 |     let f = match f {
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]   --> a4_ownership/main.rs:35:9
[INFO] [stdout]    |
[INFO] [stdout] 35 |     let s = "runoob"; // 这里是变量 s 的可用范围
[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: unused variable: `a`
[INFO] [stdout]   --> a4_ownership/main.rs:39:13
[INFO] [stdout]    |
[INFO] [stdout] 39 |         let a = "hello";
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> a4_ownership/main.rs:74:9
[INFO] [stdout]    |
[INFO] [stdout] 74 |     let y = x;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s2`
[INFO] [stdout]   --> a4_ownership/main.rs:78:9
[INFO] [stdout]    |
[INFO] [stdout] 78 |     let s2 = s1;
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_s2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s2`
[INFO] [stdout]    --> a4_ownership/main.rs:100:9
[INFO] [stdout]     |
[INFO] [stdout] 100 |     let s2 = s1;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_s2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s1`
[INFO] [stdout]    --> a4_ownership/main.rs:165:9
[INFO] [stdout]     |
[INFO] [stdout] 165 |     let s1 = gives_ownership(); // gives_ownership 移动它的返回值到 s1
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_s1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s3`
[INFO] [stdout]    --> a4_ownership/main.rs:169:9
[INFO] [stdout]     |
[INFO] [stdout] 169 |     let s3 = takes_and_gives_back(s2); // s2 被当作参数移动, s3 获得返回值所有权
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_s3`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r1`
[INFO] [stdout]    --> a4_ownership/main.rs:217:9
[INFO] [stdout]     |
[INFO] [stdout] 217 |     let r1 = &mut s;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_r1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> a4_ownership/main.rs:233:18
[INFO] [stdout]     |
[INFO] [stdout] 233 | fn cannot_change(s: &String) {
[INFO] [stdout]     |                  ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r1`
[INFO] [stdout]    --> a4_ownership/main.rs:259:13
[INFO] [stdout]     |
[INFO] [stdout] 259 |         let r1 = &mut s;
[INFO] [stdout]     |             ^^ help: if this is intentional, prefix it with an underscore: `_r1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s3`
[INFO] [stdout]    --> a4_ownership/main.rs:261:9
[INFO] [stdout]     |
[INFO] [stdout] 261 |     let s3 = &mut s;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_s3`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s1`
[INFO] [stdout]    --> a4_ownership/main.rs:267:9
[INFO] [stdout]     |
[INFO] [stdout] 267 |     let s1 = &s;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_s1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s2`
[INFO] [stdout]    --> a4_ownership/main.rs:268:9
[INFO] [stdout]     |
[INFO] [stdout] 268 |     let s2 = &s;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_s2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `s2` is never read
[INFO] [stdout]    --> a4_ownership/main.rs:302:13
[INFO] [stdout]     |
[INFO] [stdout] 302 |     let mut s2 = &s1;
[INFO] [stdout]     |             ^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `file`
[INFO] [stdout]    --> a9_error/src/main.rs:116:15
[INFO] [stdout]     |
[INFO] [stdout] 116 |     if let Ok(file) = f {
[INFO] [stdout]     |               ^^^^ help: if this is intentional, prefix it with an underscore: `_file`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f1`
[INFO] [stdout]    --> a9_error/src/main.rs:129:9
[INFO] [stdout]     |
[INFO] [stdout] 129 |     let f1 = File::open("hello.txt").unwrap();
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_f1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f2`
[INFO] [stdout]    --> a9_error/src/main.rs:130:9
[INFO] [stdout]     |
[INFO] [stdout] 130 |     let f2 = File::open("hello.txt").expect("Failed to open.");
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_f2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]    --> a9_error/src/main.rs:235:9
[INFO] [stdout]     |
[INFO] [stdout] 235 |     let f = File::open("hello.txt")?;
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `scope`
[INFO] [stdout]   --> a4_ownership/main.rs:33:4
[INFO] [stdout]    |
[INFO] [stdout] 33 | fn scope() {
[INFO] [stdout]    |    ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]   --> a8_common_collections/src/main.rs:23:9
[INFO] [stdout]    |
[INFO] [stdout] 23 |     let v: Vec<i32> = Vec::new();
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `does_not_exist`
[INFO] [stdout]   --> a8_common_collections/src/main.rs:60:9
[INFO] [stdout]    |
[INFO] [stdout] 60 |     let does_not_exist = v.get(100);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_does_not_exist`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]   --> a8_common_collections/src/main.rs:74:13
[INFO] [stdout]    |
[INFO] [stdout] 74 |     let mut v = vec![1, 2, 3, 4, 5];
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `str`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:142:9
[INFO] [stdout]     |
[INFO] [stdout] 142 |     let str = String::new();
[INFO] [stdout]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_str`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:147:9
[INFO] [stdout]     |
[INFO] [stdout] 147 |     let s = data.to_string();
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:150:9
[INFO] [stdout]     |
[INFO] [stdout] 150 |     let s = "Initail contents".to_string();
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:156:9
[INFO] [stdout]     |
[INFO] [stdout] 156 |     let hello = String::from("السلام عليكم");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:157:9
[INFO] [stdout]     |
[INFO] [stdout] 157 |     let hello = String::from("Dobrý den");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:158:9
[INFO] [stdout]     |
[INFO] [stdout] 158 |     let hello = String::from("Hello");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:159:9
[INFO] [stdout]     |
[INFO] [stdout] 159 |     let hello = String::from("שָׁלוֹם");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:164:9
[INFO] [stdout]     |
[INFO] [stdout] 164 |     let hello = String::from("안녕하세요");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:169:9
[INFO] [stdout]     |
[INFO] [stdout] 169 |     let hello = String::from("Здравствуйте");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:170:9
[INFO] [stdout]     |
[INFO] [stdout] 170 |     let hello = String::from("Hola");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `one`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:186:9
[INFO] [stdout]     |
[INFO] [stdout] 186 |     let one = 1.to_string();
[INFO] [stdout]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_one`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `float`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:187:9
[INFO] [stdout]     |
[INFO] [stdout] 187 |     let float = 1.3.to_string();
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_float`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `slice`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:188:9
[INFO] [stdout]     |
[INFO] [stdout] 188 |     let slice = "slice".to_string();
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_slice`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `len`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:222:9
[INFO] [stdout]     |
[INFO] [stdout] 222 |     let len = s.len();
[INFO] [stdout]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_len`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `len`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:225:9
[INFO] [stdout]     |
[INFO] [stdout] 225 |     let len = s.chars().count();
[INFO] [stdout]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_len`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:228:9
[INFO] [stdout]     |
[INFO] [stdout] 228 |     let a = s.chars().nth(2);
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `combine`
[INFO] [stdout]    --> a8_common_collections/src/main.rs:264:13
[INFO] [stdout]     |
[INFO] [stdout] 264 |     let mut combine: HashMap<_, _> = teams.iter().zip(scores.iter()).collect();
[INFO] [stdout]     |             ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_combine`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> a8_common_collections/src/main.rs:55:9
[INFO] [stdout]    |
[INFO] [stdout] 55 |     let mut v = vec![1, 2, 3, 4, 5];
[INFO] [stdout]    |         ----^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> a8_common_collections/src/main.rs:74:9
[INFO] [stdout]    |
[INFO] [stdout] 74 |     let mut v = vec![1, 2, 3, 4, 5];
[INFO] [stdout]    |         ----^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `foo`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:118:4
[INFO] [stdout]     |
[INFO] [stdout] 118 | fn foo(x: i32) {}
[INFO] [stdout]     |    ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `print_coordinates`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:119:4
[INFO] [stdout]     |
[INFO] [stdout] 119 | fn print_coordinates(&(x, y): &(i32, i32)) {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Quit`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:241:5
[INFO] [stdout]     |
[INFO] [stdout] 241 |     Quit,
[INFO] [stdout]     |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Move`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:242:5
[INFO] [stdout]     |
[INFO] [stdout] 242 |     Move { x: i32, y: i32 },
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Write`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:243:5
[INFO] [stdout]     |
[INFO] [stdout] 243 |     Write(String),
[INFO] [stdout]     |     ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Rgb`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:263:5
[INFO] [stdout]     |
[INFO] [stdout] 263 |     Rgb(i32, i32, i32),
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Quit`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:267:5
[INFO] [stdout]     |
[INFO] [stdout] 267 |     Quit,
[INFO] [stdout]     |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Move`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:268:5
[INFO] [stdout]     |
[INFO] [stdout] 268 |     Move { x: i32, y: i32 },
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Write`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:269:5
[INFO] [stdout]     |
[INFO] [stdout] 269 |     Write(String),
[INFO] [stdout]     |     ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `y`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:362:5
[INFO] [stdout]     |
[INFO] [stdout] 362 |     y: i32,
[INFO] [stdout]     |     ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `z`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:363:5
[INFO] [stdout]     |
[INFO] [stdout] 363 |     z: i32,
[INFO] [stdout]     |     ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `match_guard`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:389:4
[INFO] [stdout]     |
[INFO] [stdout] 389 | fn match_guard() {
[INFO] [stdout]     |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `panic_error`
[INFO] [stdout]   --> a9_error/src/main.rs:44:4
[INFO] [stdout]    |
[INFO] [stdout] 44 | fn panic_error() {
[INFO] [stdout]    |    ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `deal_file`
[INFO] [stdout]   --> a9_error/src/main.rs:62:4
[INFO] [stdout]    |
[INFO] [stdout] 62 | fn deal_file() {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `match_error_kind`
[INFO] [stdout]   --> a9_error/src/main.rs:79:4
[INFO] [stdout]    |
[INFO] [stdout] 79 | fn match_error_kind() {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `match_error_closure`
[INFO] [stdout]   --> a9_error/src/main.rs:96:4
[INFO] [stdout]    |
[INFO] [stdout] 96 | fn match_error_closure() {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `deal_file_2`
[INFO] [stdout]    --> a9_error/src/main.rs:114:4
[INFO] [stdout]     |
[INFO] [stdout] 114 | fn deal_file_2() {
[INFO] [stdout]     |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `deal_file_error`
[INFO] [stdout]    --> a9_error/src/main.rs:128:4
[INFO] [stdout]     |
[INFO] [stdout] 128 | fn deal_file_error() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `deliver_error`
[INFO] [stdout]    --> a9_error/src/main.rs:135:4
[INFO] [stdout]     |
[INFO] [stdout] 135 | fn deliver_error(i: i32) {
[INFO] [stdout]     |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `f`
[INFO] [stdout]    --> a9_error/src/main.rs:144:4
[INFO] [stdout]     |
[INFO] [stdout] 144 | fn f(i: i32) -> Result<i32, bool> {
[INFO] [stdout]     |    ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `g1`
[INFO] [stdout]    --> a9_error/src/main.rs:154:4
[INFO] [stdout]     |
[INFO] [stdout] 154 | fn g1(i: i32) -> Result<i32, bool> {
[INFO] [stdout]     |    ^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `g`
[INFO] [stdout]    --> a9_error/src/main.rs:166:4
[INFO] [stdout]     |
[INFO] [stdout] 166 | fn g(i: i32) -> Result<i32, bool> {
[INFO] [stdout]     |    ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `read_username_from_file`
[INFO] [stdout]    --> a9_error/src/main.rs:174:4
[INFO] [stdout]     |
[INFO] [stdout] 174 | fn read_username_from_file() -> Result<String, io::Error> {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `read_username_from_file_short`
[INFO] [stdout]    --> a9_error/src/main.rs:188:4
[INFO] [stdout]     |
[INFO] [stdout] 188 | fn read_username_from_file_short() -> Result<String, io::Error> {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `read_text_from_file`
[INFO] [stdout]    --> a9_error/src/main.rs:209:4
[INFO] [stdout]     |
[INFO] [stdout] 209 | fn read_text_from_file(path: &str) -> Result<String, io::Error> {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `deal_good`
[INFO] [stdout]    --> a9_error/src/main.rs:216:4
[INFO] [stdout]     |
[INFO] [stdout] 216 | fn deal_good() {
[INFO] [stdout]     |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> a8_common_collections/src/main.rs:264:9
[INFO] [stdout]     |
[INFO] [stdout] 264 |     let mut combine: HashMap<_, _> = teams.iter().zip(scores.iter()).collect();
[INFO] [stdout]     |         ----^^^^^^^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `a` is never read
[INFO] [stdout]    --> a3_common_concepts/main.rs:135:13
[INFO] [stdout]     |
[INFO] [stdout] 135 |     let mut a = 123;
[INFO] [stdout]     |             ^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]    --> a3_common_concepts/main.rs:143:9
[INFO] [stdout]     |
[INFO] [stdout] 143 |     let b = 123;
[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 variable: `b`
[INFO] [stdout]    --> a3_common_concepts/main.rs:144:9
[INFO] [stdout]     |
[INFO] [stdout] 144 |     let b = "456";
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]    --> a3_common_concepts/main.rs:155:9
[INFO] [stdout]     |
[INFO] [stdout] 155 |     let y = 2.0; // f64
[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]    --> a3_common_concepts/main.rs:156:9
[INFO] [stdout]     |
[INFO] [stdout] 156 |     let x: f32 = 10.1; //f32
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]    --> a3_common_concepts/main.rs:158:9
[INFO] [stdout]     |
[INFO] [stdout] 158 |     let t = true;
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_t`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]    --> a3_common_concepts/main.rs:159:9
[INFO] [stdout]     |
[INFO] [stdout] 159 |     let f: bool = false;
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]    --> a3_common_concepts/main.rs:161:9
[INFO] [stdout]     |
[INFO] [stdout] 161 |     let c = 'z';
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `z`
[INFO] [stdout]    --> a3_common_concepts/main.rs:162:9
[INFO] [stdout]     |
[INFO] [stdout] 162 |     let z = 'Z';
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_z`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `heart_eyed_cat`
[INFO] [stdout]    --> a3_common_concepts/main.rs:163:9
[INFO] [stdout]     |
[INFO] [stdout] 163 |     let heart_eyed_cat = '😻';
[INFO] [stdout]     |         ^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_heart_eyed_cat`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tup`
[INFO] [stdout]    --> a3_common_concepts/main.rs:165:9
[INFO] [stdout]     |
[INFO] [stdout] 165 |     let tup = (100, 2.5, -80);
[INFO] [stdout]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_tup`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]    --> a3_common_concepts/main.rs:169:10
[INFO] [stdout]     |
[INFO] [stdout] 169 |     let (x, y, z) = tup;
[INFO] [stdout]     |          ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `z`
[INFO] [stdout]    --> a3_common_concepts/main.rs:169:16
[INFO] [stdout]     |
[INFO] [stdout] 169 |     let (x, y, z) = tup;
[INFO] [stdout]     |                ^ help: if this is intentional, prefix it with an underscore: `_z`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t1`
[INFO] [stdout]    --> a3_common_concepts/main.rs:172:9
[INFO] [stdout]     |
[INFO] [stdout] 172 |     let t1 = tup.0;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_t1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t3`
[INFO] [stdout]    --> a3_common_concepts/main.rs:173:9
[INFO] [stdout]     |
[INFO] [stdout] 173 |     let t3 = tup.2;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_t3`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `arr`
[INFO] [stdout]    --> a3_common_concepts/main.rs:175:9
[INFO] [stdout]     |
[INFO] [stdout] 175 |     let arr = [1, 2, 3, 4, 5, 6];
[INFO] [stdout]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_arr`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `months`
[INFO] [stdout]    --> a3_common_concepts/main.rs:176:9
[INFO] [stdout]     |
[INFO] [stdout] 176 |     let months = [
[INFO] [stdout]     |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_months`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `array`
[INFO] [stdout]    --> a3_common_concepts/main.rs:191:9
[INFO] [stdout]     |
[INFO] [stdout] 191 |     let array: [i32; 5] = [1, 2, 3, 4, 10];
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_array`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]    --> a3_common_concepts/main.rs:260:9
[INFO] [stdout]     |
[INFO] [stdout] 260 |     let a = 10; // end line commets
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `lucky_number`
[INFO] [stdout]    --> a3_common_concepts/main.rs:265:9
[INFO] [stdout]     |
[INFO] [stdout] 265 |     let lucky_number = 1;
[INFO] [stdout]     |         ^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_lucky_number`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> a3_common_concepts/main.rs:140:9
[INFO] [stdout]     |
[INFO] [stdout] 140 |     let mut a = 50;
[INFO] [stdout]     |         ----^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant is never used: `MAX_POINT`
[INFO] [stdout]    --> a3_common_concepts/main.rs:146:5
[INFO] [stdout]     |
[INFO] [stdout] 146 |     const MAX_POINT: u32 = 1000_1000;
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `domain`
[INFO] [stdout]   --> a5_structs/main.rs:12:5
[INFO] [stdout]    |
[INFO] [stdout] 12 |     domain: String,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `name`
[INFO] [stdout]   --> a5_structs/main.rs:13:5
[INFO] [stdout]    |
[INFO] [stdout] 13 |     name: String,
[INFO] [stdout]    |     ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `found`
[INFO] [stdout]   --> a5_structs/main.rs:15:5
[INFO] [stdout]    |
[INFO] [stdout] 15 |     found: u32,
[INFO] [stdout]    |     ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Like`
[INFO] [stdout]    --> a5_structs/main.rs:111:8
[INFO] [stdout]     |
[INFO] [stdout] 111 | struct Like {}
[INFO] [stdout]     |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `test`
[INFO] [stdout]    --> a5_structs/main.rs:170:8
[INFO] [stdout]     |
[INFO] [stdout] 170 |     fn test(self, s: &str) {
[INFO] [stdout]     |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `UnitStruct`
[INFO] [stdout]    --> a5_structs/main.rs:201:8
[INFO] [stdout]     |
[INFO] [stdout] 201 | struct UnitStruct;
[INFO] [stdout]     |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `create_Rectangle` should have a snake case name
[INFO] [stdout]    --> a5_structs/main.rs:192:4
[INFO] [stdout]     |
[INFO] [stdout] 192 | fn create_Rectangle() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^ help: convert the identifier to snake case: `create_rectangle`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(non_snake_case)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type `List_Rc` should have an upper camel case name
[INFO] [stdout]    --> a15_pointers/src/main.rs:297:6
[INFO] [stdout]     |
[INFO] [stdout] 297 | enum List_Rc {
[INFO] [stdout]     |      ^^^^^^^ help: convert the identifier to upper camel case: `ListRc`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(non_camel_case_types)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `item`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:200:11
[INFO] [stdout]     |
[INFO] [stdout] 200 | fn notify(item: impl Summary + Display) {}
[INFO] [stdout]     |           ^^^^ help: if this is intentional, prefix it with an underscore: `_item`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `item`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:201:34
[INFO] [stdout]     |
[INFO] [stdout] 201 | fn notify1<T: Summary + Display>(item: T) {}
[INFO] [stdout]     |                                  ^^^^ help: if this is intentional, prefix it with an underscore: `_item`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:204:56
[INFO] [stdout]     |
[INFO] [stdout] 204 | fn some_function<T: Display + Clone, U: Clone + Debug>(t: T, u: U) {}
[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]    --> a10_generic_traits_lifetime/src/main.rs:204:62
[INFO] [stdout]     |
[INFO] [stdout] 204 | fn some_function<T: Display + Clone, U: Clone + Debug>(t: T, u: U) {}
[INFO] [stdout]     |                                                              ^ help: if this is intentional, prefix it with an underscore: `_u`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:206:25
[INFO] [stdout]     |
[INFO] [stdout] 206 | fn some_function1<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]    --> a10_generic_traits_lifetime/src/main.rs:206:31
[INFO] [stdout]     |
[INFO] [stdout] 206 | fn some_function1<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: `a`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:229:9
[INFO] [stdout]     |
[INFO] [stdout] 229 |     let a = [2, 4, 5, 3, 8];
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `y`
[INFO] [stdout]   --> a10_generic_traits_lifetime/src/main.rs:31:5
[INFO] [stdout]    |
[INFO] [stdout] 31 |     y: T,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Point1`
[INFO] [stdout]   --> a10_generic_traits_lifetime/src/main.rs:36:8
[INFO] [stdout]    |
[INFO] [stdout] 36 | struct Point1<T, U> {
[INFO] [stdout]    |        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `Option`
[INFO] [stdout]   --> a10_generic_traits_lifetime/src/main.rs:48:6
[INFO] [stdout]    |
[INFO] [stdout] 48 | enum Option<T> {
[INFO] [stdout]    |      ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `Result`
[INFO] [stdout]   --> a10_generic_traits_lifetime/src/main.rs:54:6
[INFO] [stdout]    |
[INFO] [stdout] 54 | enum Result<T, E> {
[INFO] [stdout]    |      ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `distance_from_orgin`
[INFO] [stdout]   --> a10_generic_traits_lifetime/src/main.rs:71:8
[INFO] [stdout]    |
[INFO] [stdout] 71 |     fn distance_from_orgin(&self) -> f32 {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Data`
[INFO] [stdout]   --> a10_generic_traits_lifetime/src/main.rs:77:8
[INFO] [stdout]    |
[INFO] [stdout] 77 | struct Data<T, U> {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `mixup`
[INFO] [stdout]   --> a10_generic_traits_lifetime/src/main.rs:83:8
[INFO] [stdout]    |
[INFO] [stdout] 83 |     fn mixup<V, W>(self, other: Data<V, W>) -> Data<T, W> {
[INFO] [stdout]    |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `printArticle`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:164:4
[INFO] [stdout]     |
[INFO] [stdout] 164 | fn printArticle() {
[INFO] [stdout]     |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `output`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:183:4
[INFO] [stdout]     |
[INFO] [stdout] 183 | fn output(object: impl Descriptive) {
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `output1`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:194:4
[INFO] [stdout]     |
[INFO] [stdout] 194 | fn output1<T: Descriptive>(object: T) {
[INFO] [stdout]     |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `notify`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:200:4
[INFO] [stdout]     |
[INFO] [stdout] 200 | fn notify(item: impl Summary + Display) {}
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `notify1`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:201:4
[INFO] [stdout]     |
[INFO] [stdout] 201 | fn notify1<T: Summary + Display>(item: T) {}
[INFO] [stdout]     |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `some_function`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:204:4
[INFO] [stdout]     |
[INFO] [stdout] 204 | fn some_function<T: Display + Clone, U: Clone + Debug>(t: T, u: U) {}
[INFO] [stdout]     |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `some_function1`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:206:4
[INFO] [stdout]     |
[INFO] [stdout] 206 | fn some_function1<T, U>(t: T, u: U) -> i32
[INFO] [stdout]     |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `returns_summarizable_1`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:216:4
[INFO] [stdout]     |
[INFO] [stdout] 216 | fn returns_summarizable_1() -> impl Summary {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `deal_file`
[INFO] [stdout]   --> a9_error/src/main.rs:62:4
[INFO] [stdout]    |
[INFO] [stdout] 62 | fn deal_file() {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `match_error_kind`
[INFO] [stdout]   --> a9_error/src/main.rs:79:4
[INFO] [stdout]    |
[INFO] [stdout] 79 | fn match_error_kind() {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `match_error_closure`
[INFO] [stdout]   --> a9_error/src/main.rs:96:4
[INFO] [stdout]    |
[INFO] [stdout] 96 | fn match_error_closure() {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `deal_file_2`
[INFO] [stdout]    --> a9_error/src/main.rs:114:4
[INFO] [stdout]     |
[INFO] [stdout] 114 | fn deal_file_2() {
[INFO] [stdout]     |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `deal_file_error`
[INFO] [stdout]    --> a9_error/src/main.rs:128:4
[INFO] [stdout]     |
[INFO] [stdout] 128 | fn deal_file_error() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `deliver_error`
[INFO] [stdout]    --> a9_error/src/main.rs:135:4
[INFO] [stdout]     |
[INFO] [stdout] 135 | fn deliver_error(i: i32) {
[INFO] [stdout]     |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `f`
[INFO] [stdout]    --> a9_error/src/main.rs:144:4
[INFO] [stdout]     |
[INFO] [stdout] 144 | fn f(i: i32) -> Result<i32, bool> {
[INFO] [stdout]     |    ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `g1`
[INFO] [stdout]    --> a9_error/src/main.rs:154:4
[INFO] [stdout]     |
[INFO] [stdout] 154 | fn g1(i: i32) -> Result<i32, bool> {
[INFO] [stdout]     |    ^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `g`
[INFO] [stdout]    --> a9_error/src/main.rs:166:4
[INFO] [stdout]     |
[INFO] [stdout] 166 | fn g(i: i32) -> Result<i32, bool> {
[INFO] [stdout]     |    ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `read_username_from_file`
[INFO] [stdout]    --> a9_error/src/main.rs:174:4
[INFO] [stdout]     |
[INFO] [stdout] 174 | fn read_username_from_file() -> Result<String, io::Error> {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `read_username_from_file_short`
[INFO] [stdout]    --> a9_error/src/main.rs:188:4
[INFO] [stdout]     |
[INFO] [stdout] 188 | fn read_username_from_file_short() -> Result<String, io::Error> {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `read_text_from_file`
[INFO] [stdout]    --> a9_error/src/main.rs:209:4
[INFO] [stdout]     |
[INFO] [stdout] 209 | fn read_text_from_file(path: &str) -> Result<String, io::Error> {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `deal_good`
[INFO] [stdout]    --> a9_error/src/main.rs:216:4
[INFO] [stdout]     |
[INFO] [stdout] 216 | fn deal_good() {
[INFO] [stdout]     |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `printArticle` should have a snake case name
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:164:4
[INFO] [stdout]     |
[INFO] [stdout] 164 | fn printArticle() {
[INFO] [stdout]     |    ^^^^^^^^^^^^ help: convert the identifier to snake case: `print_article`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(non_snake_case)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `post`
[INFO] [stdout]   --> a17_oop/src/blog.rs:59:27
[INFO] [stdout]    |
[INFO] [stdout] 59 |     fn content<'a>(&self, post: &'a Post) -> &'a str {
[INFO] [stdout]    |                           ^^^^ help: if this is intentional, prefix it with an underscore: `_post`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `item`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:200:11
[INFO] [stdout]     |
[INFO] [stdout] 200 | fn notify(item: impl Summary + Display) {}
[INFO] [stdout]     |           ^^^^ help: if this is intentional, prefix it with an underscore: `_item`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `item`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:201:34
[INFO] [stdout]     |
[INFO] [stdout] 201 | fn notify1<T: Summary + Display>(item: T) {}
[INFO] [stdout]     |                                  ^^^^ help: if this is intentional, prefix it with an underscore: `_item`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:204:56
[INFO] [stdout]     |
[INFO] [stdout] 204 | fn some_function<T: Display + Clone, U: Clone + Debug>(t: T, u: U) {}
[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]    --> a10_generic_traits_lifetime/src/main.rs:204:62
[INFO] [stdout]     |
[INFO] [stdout] 204 | fn some_function<T: Display + Clone, U: Clone + Debug>(t: T, u: U) {}
[INFO] [stdout]     |                                                              ^ help: if this is intentional, prefix it with an underscore: `_u`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:206:25
[INFO] [stdout]     |
[INFO] [stdout] 206 | fn some_function1<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]    --> a10_generic_traits_lifetime/src/main.rs:206:31
[INFO] [stdout]     |
[INFO] [stdout] 206 | fn some_function1<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: `a`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:229:9
[INFO] [stdout]     |
[INFO] [stdout] 229 |     let a = [2, 4, 5, 3, 8];
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `y`
[INFO] [stdout]   --> a10_generic_traits_lifetime/src/main.rs:31:5
[INFO] [stdout]    |
[INFO] [stdout] 31 |     y: T,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Screen`
[INFO] [stdout]    --> a17_oop/src/main.rs:167:16
[INFO] [stdout]     |
[INFO] [stdout] 167 |     pub struct Screen<T: Draw> {
[INFO] [stdout]     |                ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `run`
[INFO] [stdout]    --> a17_oop/src/main.rs:175:16
[INFO] [stdout]     |
[INFO] [stdout] 175 |         pub fn run(&self) {
[INFO] [stdout]     |                ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Screen`
[INFO] [stdout]    --> a17_oop/src/main.rs:220:16
[INFO] [stdout]     |
[INFO] [stdout] 220 |     pub struct Screen {
[INFO] [stdout]     |                ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book`
[INFO] [stdout]   --> a6_enums_match/main.rs:87:9
[INFO] [stdout]    |
[INFO] [stdout] 87 |     let book = Book::Papery { index: 1001 };
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_book`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `ebook`
[INFO] [stdout]    --> a6_enums_match/main.rs:159:9
[INFO] [stdout]     |
[INFO] [stdout] 159 |     let ebook = Book::Electronic {
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_ebook`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book`
[INFO] [stdout]   --> a6_enums_match/main.rs:87:9
[INFO] [stdout]    |
[INFO] [stdout] 87 |     let book = Book::Papery { index: 1001 };
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_book`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `ebook`
[INFO] [stdout]    --> a6_enums_match/main.rs:159:9
[INFO] [stdout]     |
[INFO] [stdout] 159 |     let ebook = Book::Electronic {
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_ebook`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:111:9
[INFO] [stdout]     |
[INFO] [stdout] 111 |     let a = 6;
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `domain`
[INFO] [stdout]   --> a5_structs/main.rs:12:5
[INFO] [stdout]    |
[INFO] [stdout] 12 |     domain: 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]    --> a18_patterns_matching/src/main.rs:112:10
[INFO] [stdout]     |
[INFO] [stdout] 112 |     let (x, y, z) = (1, 2, 3);
[INFO] [stdout]     |          ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:112:13
[INFO] [stdout]     |
[INFO] [stdout] 112 |     let (x, y, z) = (1, 2, 3);
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `z`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:112:16
[INFO] [stdout]     |
[INFO] [stdout] 112 |     let (x, y, z) = (1, 2, 3);
[INFO] [stdout]     |                ^ help: if this is intentional, prefix it with an underscore: `_z`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:118:8
[INFO] [stdout]     |
[INFO] [stdout] 118 | fn foo(x: i32) {}
[INFO] [stdout]     |        ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `name`
[INFO] [stdout]   --> a5_structs/main.rs:13:5
[INFO] [stdout]    |
[INFO] [stdout] 13 |     name: String,
[INFO] [stdout]    |     ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `found`
[INFO] [stdout]   --> a5_structs/main.rs:15:5
[INFO] [stdout]    |
[INFO] [stdout] 15 |     found: u32,
[INFO] [stdout]    |     ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Like`
[INFO] [stdout]    --> a5_structs/main.rs:111:8
[INFO] [stdout]     |
[INFO] [stdout] 111 | struct Like {}
[INFO] [stdout]     |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `test`
[INFO] [stdout]    --> a5_structs/main.rs:170:8
[INFO] [stdout]     |
[INFO] [stdout] 170 |     fn test(self, s: &str) {
[INFO] [stdout]     |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `UnitStruct`
[INFO] [stdout]    --> a5_structs/main.rs:201:8
[INFO] [stdout]     |
[INFO] [stdout] 201 | struct UnitStruct;
[INFO] [stdout]     |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `create_Rectangle` should have a snake case name
[INFO] [stdout]    --> a5_structs/main.rs:192:4
[INFO] [stdout]     |
[INFO] [stdout] 192 | fn create_Rectangle() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^ help: convert the identifier to snake case: `create_rectangle`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(non_snake_case)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `feet`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:291:11
[INFO] [stdout]     |
[INFO] [stdout] 291 |     let ((feet, inches), Point { x, y }) = ((3, 10), Point { x: 3, y: -10 });
[INFO] [stdout]     |           ^^^^ help: if this is intentional, prefix it with an underscore: `_feet`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Ipv4Addr`
[INFO] [stdout]   --> a6_enums_match/main.rs:49:12
[INFO] [stdout]    |
[INFO] [stdout] 49 |     struct Ipv4Addr {}
[INFO] [stdout]    |            ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `cannot_change`
[INFO] [stdout]    --> a4_ownership/main.rs:233:4
[INFO] [stdout]     |
[INFO] [stdout] 233 | fn cannot_change(s: &String) {
[INFO] [stdout]     |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `inches`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:291:17
[INFO] [stdout]     |
[INFO] [stdout] 291 |     let ((feet, inches), Point { x, y }) = ((3, 10), Point { x: 3, y: -10 });
[INFO] [stdout]     |                 ^^^^^^ help: if this is intentional, prefix it with an underscore: `_inches`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:291:34
[INFO] [stdout]     |
[INFO] [stdout] 291 |     let ((feet, inches), Point { x, y }) = ((3, 10), Point { x: 3, y: -10 });
[INFO] [stdout]     |                                  ^ help: try ignoring the field: `x: _`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:291:37
[INFO] [stdout]     |
[INFO] [stdout] 291 |     let ((feet, inches), Point { x, y }) = ((3, 10), Point { x: 3, y: -10 });
[INFO] [stdout]     |                                     ^ help: try ignoring the field: `y: _`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:348:9
[INFO] [stdout]     |
[INFO] [stdout] 348 |     let y = 10;
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Ipv6Addr`
[INFO] [stdout]   --> a6_enums_match/main.rs:51:12
[INFO] [stdout]    |
[INFO] [stdout] 51 |     struct Ipv6Addr {}
[INFO] [stdout]    |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `IP`
[INFO] [stdout]   --> a6_enums_match/main.rs:54:10
[INFO] [stdout]    |
[INFO] [stdout] 54 |     enum IP {
[INFO] [stdout]    |          ^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `other`
[INFO] [stdout]   --> a6_enums_match/main.rs:60:4
[INFO] [stdout]    |
[INFO] [stdout] 60 | fn other() {
[INFO] [stdout]    |    ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `index`
[INFO] [stdout]   --> a6_enums_match/main.rs:84:18
[INFO] [stdout]    |
[INFO] [stdout] 84 |         Papery { index: u32 },
[INFO] [stdout]    |                  ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Electronic`
[INFO] [stdout]   --> a6_enums_match/main.rs:85:9
[INFO] [stdout]    |
[INFO] [stdout] 85 |         Electronic { url: String },
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Quit`
[INFO] [stdout]   --> a6_enums_match/main.rs:93:5
[INFO] [stdout]    |
[INFO] [stdout] 93 |     Quit,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Move`
[INFO] [stdout]   --> a6_enums_match/main.rs:94:5
[INFO] [stdout]    |
[INFO] [stdout] 94 |     Move { x: i32, y: i32 }, // anonymous struct
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `ChangeColor`
[INFO] [stdout]   --> a6_enums_match/main.rs:96:5
[INFO] [stdout]    |
[INFO] [stdout] 96 |     ChangeColor(i32, i32, i32),
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Penny`
[INFO] [stdout]    --> a6_enums_match/main.rs:124:5
[INFO] [stdout]     |
[INFO] [stdout] 124 |     Penny,
[INFO] [stdout]     |     ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Nickel`
[INFO] [stdout]    --> a6_enums_match/main.rs:125:5
[INFO] [stdout]     |
[INFO] [stdout] 125 |     Nickel,
[INFO] [stdout]     |     ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Dime`
[INFO] [stdout]    --> a6_enums_match/main.rs:126:5
[INFO] [stdout]     |
[INFO] [stdout] 126 |     Dime,
[INFO] [stdout]     |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Alabama`
[INFO] [stdout]    --> a6_enums_match/main.rs:132:5
[INFO] [stdout]     |
[INFO] [stdout] 132 |     Alabama,
[INFO] [stdout]     |     ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `simulated_expensive_calculation`
[INFO] [stdout]   --> a13_functional/src/main.rs:20:4
[INFO] [stdout]    |
[INFO] [stdout] 20 | fn simulated_expensive_calculation(intensity: u32) -> u32 {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `Iterator_count_std` should have a snake case name
[INFO] [stdout]    --> a13_functional/src/main.rs:357:4
[INFO] [stdout]     |
[INFO] [stdout] 357 | fn Iterator_count_std() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^ help: convert the identifier to snake case (notice the capitalization): `iterator_count_std`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(non_snake_case)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `channel_ownership`
[INFO] [stdout]    --> a16_concurrency/src/main.rs:197:4
[INFO] [stdout]     |
[INFO] [stdout] 197 | fn channel_ownership() {
[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: struct is never constructed: `Ipv4Addr`
[INFO] [stdout]   --> a6_enums_match/main.rs:49:12
[INFO] [stdout]    |
[INFO] [stdout] 49 |     struct Ipv4Addr {}
[INFO] [stdout]    |            ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Ipv6Addr`
[INFO] [stdout]   --> a6_enums_match/main.rs:51:12
[INFO] [stdout]    |
[INFO] [stdout] 51 |     struct Ipv6Addr {}
[INFO] [stdout]    |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `IP`
[INFO] [stdout]   --> a6_enums_match/main.rs:54:10
[INFO] [stdout]    |
[INFO] [stdout] 54 |     enum IP {
[INFO] [stdout]    |          ^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `other`
[INFO] [stdout]   --> a6_enums_match/main.rs:60:4
[INFO] [stdout]    |
[INFO] [stdout] 60 | fn other() {
[INFO] [stdout]    |    ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `index`
[INFO] [stdout]   --> a6_enums_match/main.rs:84:18
[INFO] [stdout]    |
[INFO] [stdout] 84 |         Papery { index: u32 },
[INFO] [stdout]    |                  ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Electronic`
[INFO] [stdout]   --> a6_enums_match/main.rs:85:9
[INFO] [stdout]    |
[INFO] [stdout] 85 |         Electronic { url: String },
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Quit`
[INFO] [stdout]   --> a6_enums_match/main.rs:93:5
[INFO] [stdout]    |
[INFO] [stdout] 93 |     Quit,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Move`
[INFO] [stdout]   --> a6_enums_match/main.rs:94:5
[INFO] [stdout]    |
[INFO] [stdout] 94 |     Move { x: i32, y: i32 }, // anonymous struct
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `ChangeColor`
[INFO] [stdout]   --> a6_enums_match/main.rs:96:5
[INFO] [stdout]    |
[INFO] [stdout] 96 |     ChangeColor(i32, i32, i32),
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Penny`
[INFO] [stdout]    --> a6_enums_match/main.rs:124:5
[INFO] [stdout]     |
[INFO] [stdout] 124 |     Penny,
[INFO] [stdout]     |     ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Nickel`
[INFO] [stdout]    --> a6_enums_match/main.rs:125:5
[INFO] [stdout]     |
[INFO] [stdout] 125 |     Nickel,
[INFO] [stdout]     |     ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Dime`
[INFO] [stdout]    --> a6_enums_match/main.rs:126:5
[INFO] [stdout]     |
[INFO] [stdout] 126 |     Dime,
[INFO] [stdout]     |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Alabama`
[INFO] [stdout]    --> a6_enums_match/main.rs:132:5
[INFO] [stdout]     |
[INFO] [stdout] 132 |     Alabama,
[INFO] [stdout]     |     ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `foo`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:118:4
[INFO] [stdout]     |
[INFO] [stdout] 118 | fn foo(x: i32) {}
[INFO] [stdout]     |    ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `print_coordinates`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:119:4
[INFO] [stdout]     |
[INFO] [stdout] 119 | fn print_coordinates(&(x, y): &(i32, i32)) {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Quit`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:241:5
[INFO] [stdout]     |
[INFO] [stdout] 241 |     Quit,
[INFO] [stdout]     |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Move`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:242:5
[INFO] [stdout]     |
[INFO] [stdout] 242 |     Move { x: i32, y: i32 },
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Write`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:243:5
[INFO] [stdout]     |
[INFO] [stdout] 243 |     Write(String),
[INFO] [stdout]     |     ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Rgb`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:263:5
[INFO] [stdout]     |
[INFO] [stdout] 263 |     Rgb(i32, i32, i32),
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Quit`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:267:5
[INFO] [stdout]     |
[INFO] [stdout] 267 |     Quit,
[INFO] [stdout]     |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Move`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:268:5
[INFO] [stdout]     |
[INFO] [stdout] 268 |     Move { x: i32, y: i32 },
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Write`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:269:5
[INFO] [stdout]     |
[INFO] [stdout] 269 |     Write(String),
[INFO] [stdout]     |     ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `y`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:362:5
[INFO] [stdout]     |
[INFO] [stdout] 362 |     y: i32,
[INFO] [stdout]     |     ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `z`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:363:5
[INFO] [stdout]     |
[INFO] [stdout] 363 |     z: i32,
[INFO] [stdout]     |     ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `match_guard`
[INFO] [stdout]    --> a18_patterns_matching/src/main.rs:389:4
[INFO] [stdout]     |
[INFO] [stdout] 389 | fn match_guard() {
[INFO] [stdout]     |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]    --> a15_pointers/src/main.rs:247:9
[INFO] [stdout]     |
[INFO] [stdout] 247 |     let c = CustomSmartPointer {
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `d`
[INFO] [stdout]    --> a15_pointers/src/main.rs:250:9
[INFO] [stdout]     |
[INFO] [stdout] 250 |     let d = CustomSmartPointer {
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_d`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]    --> a15_pointers/src/main.rs:312:9
[INFO] [stdout]     |
[INFO] [stdout] 312 |     let b = List_Rc::Cons(3, Rc::clone(&a));
[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]    --> a15_pointers/src/main.rs:313:9
[INFO] [stdout]     |
[INFO] [stdout] 313 |     let c = List_Rc::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: unused variable: `b`
[INFO] [stdout]    --> a15_pointers/src/main.rs:323:9
[INFO] [stdout]     |
[INFO] [stdout] 323 |     let b = List_Rc::Cons(3, Rc::clone(&a));
[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]    --> a15_pointers/src/main.rs:326:13
[INFO] [stdout]     |
[INFO] [stdout] 326 |         let c = List_Rc::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: unused variable: `x`
[INFO] [stdout]    --> a15_pointers/src/main.rs:381:9
[INFO] [stdout]     |
[INFO] [stdout] 381 |     let x = 5;
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `branch`
[INFO] [stdout]    --> a15_pointers/src/main.rs:665:13
[INFO] [stdout]     |
[INFO] [stdout] 665 |         let branch = Rc::new(Node {
[INFO] [stdout]     |             ^^^^^^ help: if this is intentional, prefix it with an underscore: `_branch`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `immutable`
[INFO] [stdout]    --> a15_pointers/src/main.rs:380:4
[INFO] [stdout]     |
[INFO] [stdout] 380 | fn immutable() {
[INFO] [stdout]     |    ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `value`
[INFO] [stdout]    --> a15_pointers/src/main.rs:649:9
[INFO] [stdout]     |
[INFO] [stdout] 649 |         value: i32,
[INFO] [stdout]     |         ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `children`
[INFO] [stdout]    --> a15_pointers/src/main.rs:650:9
[INFO] [stdout]     |
[INFO] [stdout] 650 |         children: RefCell<Vec<Rc<Node>>>,
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `tree`
[INFO] [stdout]    --> a15_pointers/src/main.rs:660:12
[INFO] [stdout]     |
[INFO] [stdout] 660 |     pub fn tree() {
[INFO] [stdout]     |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `value`
[INFO] [stdout]    --> a15_pointers/src/main.rs:687:9
[INFO] [stdout]     |
[INFO] [stdout] 687 |         value: i32,
[INFO] [stdout]     |         ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `children`
[INFO] [stdout]    --> a15_pointers/src/main.rs:689:9
[INFO] [stdout]     |
[INFO] [stdout] 689 |         children: RefCell<Vec<Rc<Node>>>,
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Point1`
[INFO] [stdout]   --> a10_generic_traits_lifetime/src/main.rs:36:8
[INFO] [stdout]    |
[INFO] [stdout] 36 | struct Point1<T, U> {
[INFO] [stdout]    |        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `Option`
[INFO] [stdout]   --> a10_generic_traits_lifetime/src/main.rs:48:6
[INFO] [stdout]    |
[INFO] [stdout] 48 | enum Option<T> {
[INFO] [stdout]    |      ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `Result`
[INFO] [stdout]   --> a10_generic_traits_lifetime/src/main.rs:54:6
[INFO] [stdout]    |
[INFO] [stdout] 54 | enum Result<T, E> {
[INFO] [stdout]    |      ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `distance_from_orgin`
[INFO] [stdout]   --> a10_generic_traits_lifetime/src/main.rs:71:8
[INFO] [stdout]    |
[INFO] [stdout] 71 |     fn distance_from_orgin(&self) -> f32 {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Data`
[INFO] [stdout]   --> a10_generic_traits_lifetime/src/main.rs:77:8
[INFO] [stdout]    |
[INFO] [stdout] 77 | struct Data<T, U> {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `mixup`
[INFO] [stdout]   --> a10_generic_traits_lifetime/src/main.rs:83:8
[INFO] [stdout]    |
[INFO] [stdout] 83 |     fn mixup<V, W>(self, other: Data<V, W>) -> Data<T, W> {
[INFO] [stdout]    |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `printArticle`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:164:4
[INFO] [stdout]     |
[INFO] [stdout] 164 | fn printArticle() {
[INFO] [stdout]     |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `output`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:183:4
[INFO] [stdout]     |
[INFO] [stdout] 183 | fn output(object: impl Descriptive) {
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `output1`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:194:4
[INFO] [stdout]     |
[INFO] [stdout] 194 | fn output1<T: Descriptive>(object: T) {
[INFO] [stdout]     |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `notify`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:200:4
[INFO] [stdout]     |
[INFO] [stdout] 200 | fn notify(item: impl Summary + Display) {}
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `notify1`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:201:4
[INFO] [stdout]     |
[INFO] [stdout] 201 | fn notify1<T: Summary + Display>(item: T) {}
[INFO] [stdout]     |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `some_function`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:204:4
[INFO] [stdout]     |
[INFO] [stdout] 204 | fn some_function<T: Display + Clone, U: Clone + Debug>(t: T, u: U) {}
[INFO] [stdout]     |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `some_function1`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:206:4
[INFO] [stdout]     |
[INFO] [stdout] 206 | fn some_function1<T, U>(t: T, u: U) -> i32
[INFO] [stdout]     |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `returns_summarizable_1`
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:216:4
[INFO] [stdout]     |
[INFO] [stdout] 216 | fn returns_summarizable_1() -> impl Summary {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `printArticle` should have a snake case name
[INFO] [stdout]    --> a10_generic_traits_lifetime/src/main.rs:164:4
[INFO] [stdout]     |
[INFO] [stdout] 164 | fn printArticle() {
[INFO] [stdout]     |    ^^^^^^^^^^^^ help: convert the identifier to snake case: `print_article`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(non_snake_case)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 22 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 23 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 15 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 22 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 16 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 16 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 22 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 23 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 20 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking rand_core v0.3.1
[INFO] [stdout] warning: 23 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking learn_rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: 7 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 20 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::*`
[INFO] [stdout]   --> a11_tests/src/main.rs:43:9
[INFO] [stdout]    |
[INFO] [stdout] 43 |     use super::*;
[INFO] [stdout]    |         ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::*`
[INFO] [stdout]    --> a11_tests/src/main.rs:101:9
[INFO] [stdout]     |
[INFO] [stdout] 101 |     use super::*;
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Rectangle`
[INFO] [stdout]   --> a11_tests/src/main.rs:32:8
[INFO] [stdout]    |
[INFO] [stdout] 32 | struct Rectangle {
[INFO] [stdout]    |        ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `value`
[INFO] [stdout]    --> a11_tests/src/main.rs:115:5
[INFO] [stdout]     |
[INFO] [stdout] 115 |     value: i32,
[INFO] [stdout]     |     ^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `can_hold`
[INFO] [stdout]   --> a11_tests/src/main.rs:37:8
[INFO] [stdout]    |
[INFO] [stdout] 37 |     fn can_hold(&self, other: &Rectangle) -> bool {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `add_two`
[INFO] [stdout]   --> a11_tests/src/main.rs:78:4
[INFO] [stdout]    |
[INFO] [stdout] 78 | fn add_two(a: i32) -> i32 {
[INFO] [stdout]    |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `greeting`
[INFO] [stdout]   --> a11_tests/src/main.rs:96:4
[INFO] [stdout]    |
[INFO] [stdout] 96 | fn greeting(name: &str) -> String {
[INFO] [stdout]    |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `value`
[INFO] [stdout]    --> a11_tests/src/main.rs:115:5
[INFO] [stdout]     |
[INFO] [stdout] 115 |     value: i32,
[INFO] [stdout]     |     ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `prints_and_returns_10`
[INFO] [stdout]    --> a11_tests/src/main.rs:197:4
[INFO] [stdout]     |
[INFO] [stdout] 197 | fn prints_and_returns_10(a: i32) -> i32 {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `add_two`
[INFO] [stdout]    --> a11_tests/src/main.rs:260:12
[INFO] [stdout]     |
[INFO] [stdout] 260 |     pub fn add_two(a: i32) -> i32 {
[INFO] [stdout]     |            ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `internal_adder`
[INFO] [stdout]    --> a11_tests/src/main.rs:264:8
[INFO] [stdout]     |
[INFO] [stdout] 264 |     fn internal_adder(a: i32, b: i32) -> i32 {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 7 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 15 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 15 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 22 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 15 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 23 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking quote v1.0.9
[INFO] [stderr]     Checking rand v0.5.6
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 10 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking a7_projects v0.1.0 (/opt/rustwide/workdir/a7_projects)
[INFO] [stderr]     Checking a2_guessing_game v0.1.0 (/opt/rustwide/workdir/a2_guessing_game)
[INFO] [stdout] warning: function is never used: `seat_at_table`
[INFO] [stdout]  --> a7_projects/src/lib.rs:5:12
[INFO] [stdout]   |
[INFO] [stdout] 5 |         fn seat_at_table() {}
[INFO] [stdout]   |            ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `take_order`
[INFO] [stdout]  --> a7_projects/src/lib.rs:9:12
[INFO] [stdout]   |
[INFO] [stdout] 9 |         fn take_order() {}
[INFO] [stdout]   |            ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `serve_order`
[INFO] [stdout]   --> a7_projects/src/lib.rs:11:12
[INFO] [stdout]    |
[INFO] [stdout] 11 |         fn serve_order() {}
[INFO] [stdout]    |            ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `take_payment`
[INFO] [stdout]   --> a7_projects/src/lib.rs:13:12
[INFO] [stdout]    |
[INFO] [stdout] 13 |         fn take_payment() {}
[INFO] [stdout]    |            ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `serve_order`
[INFO] [stdout]   --> a7_projects/src/lib.rs:38:4
[INFO] [stdout]    |
[INFO] [stdout] 38 | fn serve_order() {}
[INFO] [stdout]    |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `fix_incorrect_order`
[INFO] [stdout]   --> a7_projects/src/lib.rs:44:8
[INFO] [stdout]    |
[INFO] [stdout] 44 |     fn fix_incorrect_order() {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `cook_order`
[INFO] [stdout]   --> a7_projects/src/lib.rs:49:8
[INFO] [stdout]    |
[INFO] [stdout] 49 |     fn cook_order() {}
[INFO] [stdout]    |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `seasonal_fruit`
[INFO] [stdout]   --> a7_projects/src/lib.rs:55:9
[INFO] [stdout]    |
[INFO] [stdout] 55 |         seasonal_fruit: String, // private field
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `Person`
[INFO] [stdout]   --> a7_projects/src/lib.rs:77:14
[INFO] [stdout]    |
[INFO] [stdout] 77 |     pub enum Person {
[INFO] [stdout]    |              ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `enum_mod`
[INFO] [stdout]   --> a7_projects/src/lib.rs:83:4
[INFO] [stdout]    |
[INFO] [stdout] 83 | fn enum_mod() {
[INFO] [stdout]    |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: module `SomeModule` should have a snake case name
[INFO] [stdout]   --> a7_projects/src/lib.rs:76:5
[INFO] [stdout]    |
[INFO] [stdout] 76 | mod SomeModule {
[INFO] [stdout]    |     ^^^^^^^^^^ help: convert the identifier to snake case: `some_module`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_snake_case)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `seat_at_table`
[INFO] [stdout]  --> a7_projects/src/lib.rs:5:12
[INFO] [stdout]   |
[INFO] [stdout] 5 |         fn seat_at_table() {}
[INFO] [stdout]   |            ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `take_order`
[INFO] [stdout]  --> a7_projects/src/lib.rs:9:12
[INFO] [stdout]   |
[INFO] [stdout] 9 |         fn take_order() {}
[INFO] [stdout]   |            ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `serve_order`
[INFO] [stdout]   --> a7_projects/src/lib.rs:11:12
[INFO] [stdout]    |
[INFO] [stdout] 11 |         fn serve_order() {}
[INFO] [stdout]    |            ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `take_payment`
[INFO] [stdout]   --> a7_projects/src/lib.rs:13:12
[INFO] [stdout]    |
[INFO] [stdout] 13 |         fn take_payment() {}
[INFO] [stdout]    |            ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `serve_order`
[INFO] [stdout]   --> a7_projects/src/lib.rs:38:4
[INFO] [stdout]    |
[INFO] [stdout] 38 | fn serve_order() {}
[INFO] [stdout]    |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `fix_incorrect_order`
[INFO] [stdout]   --> a7_projects/src/lib.rs:44:8
[INFO] [stdout]    |
[INFO] [stdout] 44 |     fn fix_incorrect_order() {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `cook_order`
[INFO] [stdout]   --> a7_projects/src/lib.rs:49:8
[INFO] [stdout]    |
[INFO] [stdout] 49 |     fn cook_order() {}
[INFO] [stdout]    |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `seasonal_fruit`
[INFO] [stdout]   --> a7_projects/src/lib.rs:55:9
[INFO] [stdout]    |
[INFO] [stdout] 55 |         seasonal_fruit: String, // private field
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `Person`
[INFO] [stdout]   --> a7_projects/src/lib.rs:77:14
[INFO] [stdout]    |
[INFO] [stdout] 77 |     pub enum Person {
[INFO] [stdout]    |              ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `enum_mod`
[INFO] [stdout]   --> a7_projects/src/lib.rs:83:4
[INFO] [stdout]    |
[INFO] [stdout] 83 | fn enum_mod() {
[INFO] [stdout]    |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: module `SomeModule` should have a snake case name
[INFO] [stdout]   --> a7_projects/src/lib.rs:76:5
[INFO] [stdout]    |
[INFO] [stdout] 76 | mod SomeModule {
[INFO] [stdout]    |     ^^^^^^^^^^ help: convert the identifier to snake case: `some_module`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_snake_case)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 11 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 11 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking hello_macro_derive v0.1.0 (/opt/rustwide/workdir/hello_macro/hello_macro_derive)
[INFO] [stdout] warning: function is never used: `legislate`
[INFO] [stdout]   --> a7_projects/src/main.rs:80:16
[INFO] [stdout]    |
[INFO] [stdout] 80 |         pub fn legislate() {}
[INFO] [stdout]    |                ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `judicial`
[INFO] [stdout]   --> a7_projects/src/main.rs:84:12
[INFO] [stdout]    |
[INFO] [stdout] 84 |         fn judicial() {
[INFO] [stdout]    |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `seasonal_fruit`
[INFO] [stdout]   --> a7_projects/src/main.rs:95:9
[INFO] [stdout]    |
[INFO] [stdout] 95 |         seasonal_fruit: String, // private field
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Quene`
[INFO] [stdout]    --> a7_projects/src/main.rs:118:9
[INFO] [stdout]     |
[INFO] [stdout] 118 |         Quene,
[INFO] [stdout]     |         ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: module `SomeModule` should have a snake case name
[INFO] [stdout]    --> a7_projects/src/main.rs:115:5
[INFO] [stdout]     |
[INFO] [stdout] 115 | mod SomeModule {
[INFO] [stdout]     |     ^^^^^^^^^^ help: convert the identifier to snake case: `some_module`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(non_snake_case)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `legislate`
[INFO] [stdout]   --> a7_projects/src/main.rs:80:16
[INFO] [stdout]    |
[INFO] [stdout] 80 |         pub fn legislate() {}
[INFO] [stdout]    |                ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `judicial`
[INFO] [stdout]   --> a7_projects/src/main.rs:84:12
[INFO] [stdout]    |
[INFO] [stdout] 84 |         fn judicial() {
[INFO] [stdout]    |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `seasonal_fruit`
[INFO] [stdout]   --> a7_projects/src/main.rs:95:9
[INFO] [stdout]    |
[INFO] [stdout] 95 |         seasonal_fruit: String, // private field
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Quene`
[INFO] [stdout]    --> a7_projects/src/main.rs:118:9
[INFO] [stdout]     |
[INFO] [stdout] 118 |         Quene,
[INFO] [stdout]     |         ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: module `SomeModule` should have a snake case name
[INFO] [stdout]    --> a7_projects/src/main.rs:115:5
[INFO] [stdout]     |
[INFO] [stdout] 115 | mod SomeModule {
[INFO] [stdout]     |     ^^^^^^^^^^ help: convert the identifier to snake case: `some_module`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(non_snake_case)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking a19_advaced_features v0.1.0 (/opt/rustwide/workdir/a19_advaced_features)
[INFO] [stdout] warning: struct is never constructed: `Parser`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:351:8
[INFO] [stdout]     |
[INFO] [stdout] 351 | struct Parser<'c, 's: 'c> {
[INFO] [stdout]     |        ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Ref`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:380:8
[INFO] [stdout]     |
[INFO] [stdout] 380 | struct Ref<'a, T: 'a>(&'a T);
[INFO] [stdout]     |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `StaticRef`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:384:8
[INFO] [stdout]     |
[INFO] [stdout] 384 | struct StaticRef<T: 'static>(&'static T);
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `diameter`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:391:5
[INFO] [stdout]     |
[INFO] [stdout] 391 |     diameter: &'a i32,
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `foo`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:418:4
[INFO] [stdout]     |
[INFO] [stdout] 418 | fn foo<'a>(string: &'a str) -> StrWrap<'a> {
[INFO] [stdout]     |    ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `foo_new`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:422:4
[INFO] [stdout]     |
[INFO] [stdout] 422 | fn foo_new(string: &str) -> StrWrap<'_> {
[INFO] [stdout]     |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type alias is never used: `Thunk`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:716:1
[INFO] [stdout]     |
[INFO] [stdout] 716 | type Thunk = Box<dyn Fn() + Send + 'static>;
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `bar`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:734:4
[INFO] [stdout]     |
[INFO] [stdout] 734 | fn bar() -> ! {
[INFO] [stdout]     |    ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `no_return`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:739:4
[INFO] [stdout]     |
[INFO] [stdout] 739 | fn no_return(guess: String) {
[INFO] [stdout]     |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `loop_value`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:770:4
[INFO] [stdout]     |
[INFO] [stdout] 770 | fn loop_value() {
[INFO] [stdout]     |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `dst`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:789:4
[INFO] [stdout]     |
[INFO] [stdout] 789 | fn dst() {
[INFO] [stdout]     |    ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `generic`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:820:4
[INFO] [stdout]     |
[INFO] [stdout] 820 | fn generic<T: Sized>(t: T) {
[INFO] [stdout]     |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `generic_1`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:826:4
[INFO] [stdout]     |
[INFO] [stdout] 826 | fn generic_1<T: ?Sized>(t: &T) {
[INFO] [stdout]     |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Stop`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:886:5
[INFO] [stdout]     |
[INFO] [stdout] 886 |     Stop,
[INFO] [stdout]     |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `return_closure`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:909:4
[INFO] [stdout]     |
[INFO] [stdout] 909 | fn return_closure() -> Box<dyn Fn(i32) -> i32> {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `macro_rules`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:950:4
[INFO] [stdout]     |
[INFO] [stdout] 950 | fn macro_rules() {
[INFO] [stdout]     |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `new_Ball` should have a snake case name
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:408:4
[INFO] [stdout]     |
[INFO] [stdout] 408 | fn new_Ball() {
[INFO] [stdout]     |    ^^^^^^^^ help: convert the identifier to snake case: `new_ball`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(non_snake_case)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Parser`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:351:8
[INFO] [stdout]     |
[INFO] [stdout] 351 | struct Parser<'c, 's: 'c> {
[INFO] [stdout]     |        ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Ref`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:380:8
[INFO] [stdout]     |
[INFO] [stdout] 380 | struct Ref<'a, T: 'a>(&'a T);
[INFO] [stdout]     |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `StaticRef`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:384:8
[INFO] [stdout]     |
[INFO] [stdout] 384 | struct StaticRef<T: 'static>(&'static T);
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `diameter`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:391:5
[INFO] [stdout]     |
[INFO] [stdout] 391 |     diameter: &'a i32,
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `foo`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:418:4
[INFO] [stdout]     |
[INFO] [stdout] 418 | fn foo<'a>(string: &'a str) -> StrWrap<'a> {
[INFO] [stdout]     |    ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `foo_new`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:422:4
[INFO] [stdout]     |
[INFO] [stdout] 422 | fn foo_new(string: &str) -> StrWrap<'_> {
[INFO] [stdout]     |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type alias is never used: `Thunk`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:716:1
[INFO] [stdout]     |
[INFO] [stdout] 716 | type Thunk = Box<dyn Fn() + Send + 'static>;
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `bar`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:734:4
[INFO] [stdout]     |
[INFO] [stdout] 734 | fn bar() -> ! {
[INFO] [stdout]     |    ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `no_return`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:739:4
[INFO] [stdout]     |
[INFO] [stdout] 739 | fn no_return(guess: String) {
[INFO] [stdout]     |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `loop_value`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:770:4
[INFO] [stdout]     |
[INFO] [stdout] 770 | fn loop_value() {
[INFO] [stdout]     |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `dst`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:789:4
[INFO] [stdout]     |
[INFO] [stdout] 789 | fn dst() {
[INFO] [stdout]     |    ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `generic`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:820:4
[INFO] [stdout]     |
[INFO] [stdout] 820 | fn generic<T: Sized>(t: T) {
[INFO] [stdout]     |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `generic_1`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:826:4
[INFO] [stdout]     |
[INFO] [stdout] 826 | fn generic_1<T: ?Sized>(t: &T) {
[INFO] [stdout]     |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Stop`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:886:5
[INFO] [stdout]     |
[INFO] [stdout] 886 |     Stop,
[INFO] [stdout]     |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `return_closure`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:909:4
[INFO] [stdout]     |
[INFO] [stdout] 909 | fn return_closure() -> Box<dyn Fn(i32) -> i32> {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `macro_rules`
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:950:4
[INFO] [stdout]     |
[INFO] [stdout] 950 | fn macro_rules() {
[INFO] [stdout]     |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `new_Ball` should have a snake case name
[INFO] [stdout]    --> a19_advaced_features/src/main.rs:408:4
[INFO] [stdout]     |
[INFO] [stdout] 408 | fn new_Ball() {
[INFO] [stdout]     |    ^^^^^^^^ help: convert the identifier to snake case: `new_ball`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(non_snake_case)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 17 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 17 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 57.65s
[INFO] running `Command { std: "docker" "inspect" "0e802ad875ff5e47c0f3fd0f11b781c9d191c6434131f593a4c0bde933ad236c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0e802ad875ff5e47c0f3fd0f11b781c9d191c6434131f593a4c0bde933ad236c", kill_on_drop: false }`
[INFO] [stdout] 0e802ad875ff5e47c0f3fd0f11b781c9d191c6434131f593a4c0bde933ad236c