[INFO] cloning repository https://github.com/tnlogy/adventofcode23
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/tnlogy/adventofcode23" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftnlogy%2Fadventofcode23", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftnlogy%2Fadventofcode23'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 735a95d2558e92d151c0234d11f6c08a45d7094f
[INFO] linting tnlogy/adventofcode23 against nightly for clippy-nonminimal_bool-denied
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftnlogy%2Fadventofcode23" "/workspace/builds/worker-1-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/tnlogy/adventofcode23
[INFO] finished tweaking git repo https://github.com/tnlogy/adventofcode23
[INFO] tweaked toml for git repo https://github.com/tnlogy/adventofcode23 written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/tnlogy/adventofcode23 on toolchain nightly
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+nightly" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/tnlogy/adventofcode23 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+nightly" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+nightly" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 47f1018f364ff4a597e726beffc4b7d2558c17ca98b621e4c737cb54e93322b6
[INFO] running `Command { std: "docker" "start" "-a" "47f1018f364ff4a597e726beffc4b7d2558c17ca98b621e4c737cb54e93322b6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "47f1018f364ff4a597e726beffc4b7d2558c17ca98b621e4c737cb54e93322b6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "47f1018f364ff4a597e726beffc4b7d2558c17ca98b621e4c737cb54e93322b6", kill_on_drop: false }`
[INFO] [stdout] 47f1018f364ff4a597e726beffc4b7d2558c17ca98b621e4c737cb54e93322b6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+nightly" "clippy" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9ae38e281e34d0f56c76f66412a67a54131032f123a05c1545aa5a810439afd0
[INFO] running `Command { std: "docker" "start" "-a" "9ae38e281e34d0f56c76f66412a67a54131032f123a05c1545aa5a810439afd0", kill_on_drop: false }`
[INFO] [stderr]     Checking memchr v2.6.4
[INFO] [stderr]     Checking regex-syntax v0.8.2
[INFO] [stderr]     Checking aho-corasick v1.1.2
[INFO] [stderr]     Checking regex-automata v0.4.3
[INFO] [stderr]     Checking regex v1.10.2
[INFO] [stderr]     Checking advent23 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: statics have by default a `'static` lifetime
[INFO] [stdout]  --> src/advent23_1.rs:5:19
[INFO] [stdout]   |
[INFO] [stdout] 5 | static NUMBERS: [&'static str; 9] = ["one", "two", "three", "four", "five", "six", "seven", "eight", "nine"];
[INFO] [stdout]   |                  -^^^^^^^---- help: consider removing `'static`: `&str`
[INFO] [stdout]   |
[INFO] [stdout]   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#redundant_static_lifetimes
[INFO] [stdout]   = note: `#[warn(clippy::redundant_static_lifetimes)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: statics have by default a `'static` lifetime
[INFO] [stdout]  --> src/advent23_1.rs:5:19
[INFO] [stdout]   |
[INFO] [stdout] 5 | static NUMBERS: [&'static str; 9] = ["one", "two", "three", "four", "five", "six", "seven", "eight", "nine"];
[INFO] [stdout]   |                  -^^^^^^^---- help: consider removing `'static`: `&str`
[INFO] [stdout]   |
[INFO] [stdout]   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#redundant_static_lifetimes
[INFO] [stdout]   = note: `#[warn(clippy::redundant_static_lifetimes)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/advent23_3.rs:67:25
[INFO] [stdout]    |
[INFO] [stdout] 67 |                     let mut entry = gears.entry(format!("{}-{}", px, py)).or_insert(Vec::new());
[INFO] [stdout]    |                         ----^^^^^
[INFO] [stdout]    |                         |
[INFO] [stdout]    |                         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `key`
[INFO] [stdout]   --> src/advent23_3.rs:79:10
[INFO] [stdout]    |
[INFO] [stdout] 79 |     for (key, values) in gears.iter() {
[INFO] [stdout]    |          ^^^ help: if this is intentional, prefix it with an underscore: `_key`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: writing `&Vec` instead of `&[_]` involves a new object where a slice will do
[INFO] [stdout]  --> src/advent23_3.rs:7:17
[INFO] [stdout]   |
[INFO] [stdout] 7 | fn get_map(map: &Vec<Vec<char>>, x: usize, y: usize) -> Option<char> {
[INFO] [stdout]   |                 ^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stdout]   = note: `#[warn(clippy::ptr_arg)]` on by default
[INFO] [stdout] help: change this to
[INFO] [stdout]   |
[INFO] [stdout] 7 - fn get_map(map: &Vec<Vec<char>>, x: usize, y: usize) -> Option<char> {
[INFO] [stdout] 7 + fn get_map(map: &[Vec<char>], x: usize, y: usize) -> Option<char> {
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression creates a reference which is immediately dereferenced by the compiler
[INFO] [stdout]   --> src/advent23_3.rs:19:21
[INFO] [stdout]    |
[INFO] [stdout] 19 |     let v = get_map(&map, x, y).unwrap().to_digit(10).unwrap();
[INFO] [stdout]    |                     ^^^^ help: change this to: `map`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout]    = note: `#[warn(clippy::needless_borrow)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression creates a reference which is immediately dereferenced by the compiler
[INFO] [stdout]   --> src/advent23_3.rs:21:37
[INFO] [stdout]    |
[INFO] [stdout] 21 |         if let Some(left) = get_map(&map, x - 1, y) {
[INFO] [stdout]    |                                     ^^^^ help: change this to: `map`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of `char::is_digit` with literal radix of 10
[INFO] [stdout]   --> src/advent23_3.rs:22:16
[INFO] [stdout]    |
[INFO] [stdout] 22 |             if left.is_digit(10) {
[INFO] [stdout]    |                ^^^^^^^^^^^^^^^^^ help: try: `left.is_ascii_digit()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#is_digit_ascii_radix
[INFO] [stdout]    = note: `#[warn(clippy::is_digit_ascii_radix)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression creates a reference which is immediately dereferenced by the compiler
[INFO] [stdout]   --> src/advent23_3.rs:23:43
[INFO] [stdout]    |
[INFO] [stdout] 23 |                 return v + 10 * get_value(&map, x - 1, y);
[INFO] [stdout]    |                                           ^^^^ help: change this to: `map`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression creates a reference which is immediately dereferenced by the compiler
[INFO] [stdout]   --> src/advent23_3.rs:33:38
[INFO] [stdout]    |
[INFO] [stdout] 33 |             if let Some(v) = get_map(&map, xp, yp) {
[INFO] [stdout]    |                                      ^^^^ help: change this to: `map`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of `char::is_digit` with literal radix of 10
[INFO] [stdout]   --> src/advent23_3.rs:34:21
[INFO] [stdout]    |
[INFO] [stdout] 34 |                 if !v.is_digit(10) && !v.eq(&'.') {
[INFO] [stdout]    |                     ^^^^^^^^^^^^^^ help: try: `v.is_ascii_digit()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#is_digit_ascii_radix
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression creates a reference which is immediately dereferenced by the compiler
[INFO] [stdout]   --> src/advent23_3.rs:44:42
[INFO] [stdout]    |
[INFO] [stdout] 44 |     if let (Some(v), Some(r)) = (get_map(&map, x, y), get_map(&map, x + 1, y)) {
[INFO] [stdout]    |                                          ^^^^ help: change this to: `map`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression creates a reference which is immediately dereferenced by the compiler
[INFO] [stdout]   --> src/advent23_3.rs:44:63
[INFO] [stdout]    |
[INFO] [stdout] 44 |     if let (Some(v), Some(r)) = (get_map(&map, x, y), get_map(&map, x + 1, y)) {
[INFO] [stdout]    |                                                               ^^^^ help: change this to: `map`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of `char::is_digit` with literal radix of 10
[INFO] [stdout]   --> src/advent23_3.rs:45:12
[INFO] [stdout]    |
[INFO] [stdout] 45 |         if v.is_digit(10) && !r.is_digit(10) {
[INFO] [stdout]    |            ^^^^^^^^^^^^^^ help: try: `v.is_ascii_digit()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#is_digit_ascii_radix
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of `char::is_digit` with literal radix of 10
[INFO] [stdout]   --> src/advent23_3.rs:45:31
[INFO] [stdout]    |
[INFO] [stdout] 45 |         if v.is_digit(10) && !r.is_digit(10) {
[INFO] [stdout]    |                               ^^^^^^^^^^^^^^ help: try: `r.is_ascii_digit()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#is_digit_ascii_radix
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression creates a reference which is immediately dereferenced by the compiler
[INFO] [stdout]   --> src/advent23_3.rs:46:35
[INFO] [stdout]    |
[INFO] [stdout] 46 |             let value = get_value(&map, x, y);
[INFO] [stdout]    |                                   ^^^^ help: change this to: `map`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression creates a reference which is immediately dereferenced by the compiler
[INFO] [stdout]   --> src/advent23_3.rs:48:55
[INFO] [stdout]    |
[INFO] [stdout] 48 |             if let Some((part, x, y)) = close_to_part(&map, x, y, valueLen) {
[INFO] [stdout]    |                                                       ^^^^ help: change this to: `map`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this `.fold` can be written more succinctly using another method
[INFO] [stdout]   --> src/advent23_3.rs:81:35
[INFO] [stdout]    |
[INFO] [stdout] 81 |             let m = values.iter().fold(1, |acc, x| acc * x);
[INFO] [stdout]    |                                   ^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `product::<u32>()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unnecessary_fold
[INFO] [stdout]    = note: `#[warn(clippy::unnecessary_fold)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `valueLen` should have a snake case name
[INFO] [stdout]   --> src/advent23_3.rs:47:17
[INFO] [stdout]    |
[INFO] [stdout] 47 |             let valueLen = value.to_string().len();
[INFO] [stdout]    |                 ^^^^^^^^ help: convert the identifier to snake case: `value_len`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_snake_case)]` (part of `#[warn(nonstandard_style)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/advent23_1.rs:55:9
[INFO] [stdout]    |
[INFO] [stdout] 55 |     let mut sum = 0;
[INFO] [stdout]    |         ----^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/advent23_1.rs:55:9
[INFO] [stdout]    |
[INFO] [stdout] 55 |     let mut sum = 0;
[INFO] [stdout]    |         ----^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `sum`
[INFO] [stdout]   --> src/advent23_1.rs:55:9
[INFO] [stdout]    |
[INFO] [stdout] 55 |     let mut sum = 0;
[INFO] [stdout]    |         ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_sum`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `sum`
[INFO] [stdout]   --> src/advent23_1.rs:55:9
[INFO] [stdout]    |
[INFO] [stdout] 55 |     let mut sum = 0;
[INFO] [stdout]    |         ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_sum`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `scratch` is never used
[INFO] [stdout]  --> src/advent23_4.rs:7:4
[INFO] [stdout]   |
[INFO] [stdout] 7 | fn scratch(input: &str, copies: &mut HashMap<u32, u32>) -> Option<u32> {
[INFO] [stdout]   |    ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `scratch` is never used
[INFO] [stdout]  --> src/advent23_4.rs:7:4
[INFO] [stdout]   |
[INFO] [stdout] 7 | fn scratch(input: &str, copies: &mut HashMap<u32, u32>) -> Option<u32> {
[INFO] [stdout]   |    ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `main` is never used
[INFO] [stdout]   --> src/advent23_4.rs:35:4
[INFO] [stdout]    |
[INFO] [stdout] 35 | fn main() -> io::Result<()> {
[INFO] [stdout]    |    ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `main` is never used
[INFO] [stdout]   --> src/advent23_4.rs:35:4
[INFO] [stdout]    |
[INFO] [stdout] 35 | fn main() -> io::Result<()> {
[INFO] [stdout]    |    ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression borrows a value the compiler would automatically borrow
[INFO] [stdout]   --> src/advent23_4.rs:13:29
[INFO] [stdout]    |
[INFO] [stdout] 13 |         let match_nr: u32 = (&card[1]).parse().unwrap();
[INFO] [stdout]    |                             ^^^^^^^^^^ help: change this to: `card[1]`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout]    = note: `#[warn(clippy::needless_borrow)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression borrows a value the compiler would automatically borrow
[INFO] [stdout]   --> src/advent23_4.rs:13:29
[INFO] [stdout]    |
[INFO] [stdout] 13 |         let match_nr: u32 = (&card[1]).parse().unwrap();
[INFO] [stdout]    |                             ^^^^^^^^^^ help: change this to: `card[1]`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout]    = note: `#[warn(clippy::needless_borrow)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression creates a reference which is immediately dereferenced by the compiler
[INFO] [stdout]   --> src/advent23_4.rs:17:84
[INFO] [stdout]    |
[INFO] [stdout] 17 |         let winning_numbers: Vec<u32> = numbers.iter().filter(|n| winners.contains(&n)).cloned().collect();
[INFO] [stdout]    |                                                                                    ^^ help: change this to: `n`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: length comparison to zero
[INFO] [stdout]   --> src/advent23_4.rs:20:12
[INFO] [stdout]    |
[INFO] [stdout] 20 |         if winning_numbers.len() > 0 {
[INFO] [stdout]    |            ^^^^^^^^^^^^^^^^^^^^^^^^^ help: using `!is_empty` is clearer and more explicit: `!winning_numbers.is_empty()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#len_zero
[INFO] [stdout]    = note: `#[warn(clippy::len_zero)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression creates a reference which is immediately dereferenced by the compiler
[INFO] [stdout]   --> src/advent23_4.rs:17:84
[INFO] [stdout]    |
[INFO] [stdout] 17 |         let winning_numbers: Vec<u32> = numbers.iter().filter(|n| winners.contains(&n)).cloned().collect();
[INFO] [stdout]    |                                                                                    ^^ help: change this to: `n`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: length comparison to zero
[INFO] [stdout]   --> src/advent23_4.rs:20:12
[INFO] [stdout]    |
[INFO] [stdout] 20 |         if winning_numbers.len() > 0 {
[INFO] [stdout]    |            ^^^^^^^^^^^^^^^^^^^^^^^^^ help: using `!is_empty` is clearer and more explicit: `!winning_numbers.is_empty()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#len_zero
[INFO] [stdout]    = note: `#[warn(clippy::len_zero)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: iterating on a map's values
[INFO] [stdout]   --> src/advent23_4.rs:52:16
[INFO] [stdout]    |
[INFO] [stdout] 52 |     let sum2 = copies.iter().map(|(_match_nr, copy_nr)| copy_nr).sum::<u32>();
[INFO] [stdout]    |                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `copies.values()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#iter_kv_map
[INFO] [stdout]    = note: `#[warn(clippy::iter_kv_map)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: iterating on a map's values
[INFO] [stdout]   --> src/advent23_4.rs:52:16
[INFO] [stdout]    |
[INFO] [stdout] 52 |     let sum2 = copies.iter().map(|(_match_nr, copy_nr)| copy_nr).sum::<u32>();
[INFO] [stdout]    |                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `copies.values()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#iter_kv_map
[INFO] [stdout]    = note: `#[warn(clippy::iter_kv_map)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of `char::is_digit` with literal radix of 10
[INFO] [stdout]  --> src/advent23_1.rs:9:12
[INFO] [stdout]   |
[INFO] [stdout] 9 |         if c.is_digit(10) {
[INFO] [stdout]   |            ^^^^^^^^^^^^^^ help: try: `c.is_ascii_digit()`
[INFO] [stdout]   |
[INFO] [stdout]   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#is_digit_ascii_radix
[INFO] [stdout]   = note: `#[warn(clippy::is_digit_ascii_radix)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the loop variable `i` is used to index `NUMBERS`
[INFO] [stdout]   --> src/advent23_1.rs:14:14
[INFO] [stdout]    |
[INFO] [stdout] 14 |     for i in 0..NUMBERS.len() {
[INFO] [stdout]    |              ^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_range_loop
[INFO] [stdout]    = note: `#[warn(clippy::needless_range_loop)]` on by default
[INFO] [stdout] help: consider using an iterator and enumerate()
[INFO] [stdout]    |
[INFO] [stdout] 14 -     for i in 0..NUMBERS.len() {
[INFO] [stdout] 14 +     for (i, <item>) in NUMBERS.iter().enumerate() {
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this boolean expression can be simplified
[INFO] [stdout]   --> src/advent23_1.rs:30:16
[INFO] [stdout]    |
[INFO] [stdout] 30 |             if !first.is_some() {
[INFO] [stdout]    |                ^^^^^^^^^^^^^^^^ help: try: `first.is_none()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#nonminimal_bool
[INFO] [stdout]    = note: `#[warn(clippy::nonminimal_bool)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this boolean expression can be simplified
[INFO] [stdout]   --> src/advent23_1.rs:39:16
[INFO] [stdout]    |
[INFO] [stdout] 39 |             if !last.is_some() {
[INFO] [stdout]    |                ^^^^^^^^^^^^^^^ help: try: `last.is_none()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#nonminimal_bool
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unneeded `return` statement
[INFO] [stdout]   --> src/advent23_1.rs:47:9
[INFO] [stdout]    |
[INFO] [stdout] 47 |         return Some(a * 10 + b);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stdout]    = note: `#[warn(clippy::needless_return)]` on by default
[INFO] [stdout] help: remove `return`
[INFO] [stdout]    |
[INFO] [stdout] 47 -         return Some(a * 10 + b);
[INFO] [stdout] 47 +         Some(a * 10 + b)
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unneeded `return` statement
[INFO] [stdout]   --> src/advent23_1.rs:49:9
[INFO] [stdout]    |
[INFO] [stdout] 49 |         return None;
[INFO] [stdout]    |         ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stdout] help: remove `return`
[INFO] [stdout]    |
[INFO] [stdout] 49 -         return None;
[INFO] [stdout] 49 +         None
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of `char::is_digit` with literal radix of 10
[INFO] [stdout]  --> src/advent23_1.rs:9:12
[INFO] [stdout]   |
[INFO] [stdout] 9 |         if c.is_digit(10) {
[INFO] [stdout]   |            ^^^^^^^^^^^^^^ help: try: `c.is_ascii_digit()`
[INFO] [stdout]   |
[INFO] [stdout]   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#is_digit_ascii_radix
[INFO] [stdout]   = note: `#[warn(clippy::is_digit_ascii_radix)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the loop variable `i` is used to index `NUMBERS`
[INFO] [stdout]   --> src/advent23_1.rs:14:14
[INFO] [stdout]    |
[INFO] [stdout] 14 |     for i in 0..NUMBERS.len() {
[INFO] [stdout]    |              ^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_range_loop
[INFO] [stdout]    = note: `#[warn(clippy::needless_range_loop)]` on by default
[INFO] [stdout] help: consider using an iterator and enumerate()
[INFO] [stdout]    |
[INFO] [stdout] 14 -     for i in 0..NUMBERS.len() {
[INFO] [stdout] 14 +     for (i, <item>) in NUMBERS.iter().enumerate() {
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this boolean expression can be simplified
[INFO] [stdout]   --> src/advent23_1.rs:30:16
[INFO] [stdout]    |
[INFO] [stdout] 30 |             if !first.is_some() {
[INFO] [stdout]    |                ^^^^^^^^^^^^^^^^ help: try: `first.is_none()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#nonminimal_bool
[INFO] [stdout]    = note: `#[warn(clippy::nonminimal_bool)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this boolean expression can be simplified
[INFO] [stdout]   --> src/advent23_1.rs:39:16
[INFO] [stdout]    |
[INFO] [stdout] 39 |             if !last.is_some() {
[INFO] [stdout]    |                ^^^^^^^^^^^^^^^ help: try: `last.is_none()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#nonminimal_bool
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unneeded `return` statement
[INFO] [stdout]   --> src/advent23_1.rs:47:9
[INFO] [stdout]    |
[INFO] [stdout] 47 |         return Some(a * 10 + b);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stdout]    = note: `#[warn(clippy::needless_return)]` on by default
[INFO] [stdout] help: remove `return`
[INFO] [stdout]    |
[INFO] [stdout] 47 -         return Some(a * 10 + b);
[INFO] [stdout] 47 +         Some(a * 10 + b)
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unneeded `return` statement
[INFO] [stdout]   --> src/advent23_1.rs:49:9
[INFO] [stdout]    |
[INFO] [stdout] 49 |         return None;
[INFO] [stdout]    |         ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stdout] help: remove `return`
[INFO] [stdout]    |
[INFO] [stdout] 49 -         return None;
[INFO] [stdout] 49 +         None
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/advent23_3.rs:67:25
[INFO] [stdout]    |
[INFO] [stdout] 67 |                     let mut entry = gears.entry(format!("{}-{}", px, py)).or_insert(Vec::new());
[INFO] [stdout]    |                         ----^^^^^
[INFO] [stdout]    |                         |
[INFO] [stdout]    |                         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `key`
[INFO] [stdout]   --> src/advent23_3.rs:79:10
[INFO] [stdout]    |
[INFO] [stdout] 79 |     for (key, values) in gears.iter() {
[INFO] [stdout]    |          ^^^ help: if this is intentional, prefix it with an underscore: `_key`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: writing `&Vec` instead of `&[_]` involves a new object where a slice will do
[INFO] [stdout]  --> src/advent23_3.rs:7:17
[INFO] [stdout]   |
[INFO] [stdout] 7 | fn get_map(map: &Vec<Vec<char>>, x: usize, y: usize) -> Option<char> {
[INFO] [stdout]   |                 ^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stdout]   = note: `#[warn(clippy::ptr_arg)]` on by default
[INFO] [stdout] help: change this to
[INFO] [stdout]   |
[INFO] [stdout] 7 - fn get_map(map: &Vec<Vec<char>>, x: usize, y: usize) -> Option<char> {
[INFO] [stdout] 7 + fn get_map(map: &[Vec<char>], x: usize, y: usize) -> Option<char> {
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression creates a reference which is immediately dereferenced by the compiler
[INFO] [stdout]   --> src/advent23_3.rs:19:21
[INFO] [stdout]    |
[INFO] [stdout] 19 |     let v = get_map(&map, x, y).unwrap().to_digit(10).unwrap();
[INFO] [stdout]    |                     ^^^^ help: change this to: `map`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout]    = note: `#[warn(clippy::needless_borrow)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression creates a reference which is immediately dereferenced by the compiler
[INFO] [stdout]   --> src/advent23_3.rs:21:37
[INFO] [stdout]    |
[INFO] [stdout] 21 |         if let Some(left) = get_map(&map, x - 1, y) {
[INFO] [stdout]    |                                     ^^^^ help: change this to: `map`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of `char::is_digit` with literal radix of 10
[INFO] [stdout]   --> src/advent23_3.rs:22:16
[INFO] [stdout]    |
[INFO] [stdout] 22 |             if left.is_digit(10) {
[INFO] [stdout]    |                ^^^^^^^^^^^^^^^^^ help: try: `left.is_ascii_digit()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#is_digit_ascii_radix
[INFO] [stdout]    = note: `#[warn(clippy::is_digit_ascii_radix)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression creates a reference which is immediately dereferenced by the compiler
[INFO] [stdout]   --> src/advent23_3.rs:23:43
[INFO] [stdout]    |
[INFO] [stdout] 23 |                 return v + 10 * get_value(&map, x - 1, y);
[INFO] [stdout]    |                                           ^^^^ help: change this to: `map`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression creates a reference which is immediately dereferenced by the compiler
[INFO] [stdout]   --> src/advent23_3.rs:33:38
[INFO] [stdout]    |
[INFO] [stdout] 33 |             if let Some(v) = get_map(&map, xp, yp) {
[INFO] [stdout]    |                                      ^^^^ help: change this to: `map`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of `char::is_digit` with literal radix of 10
[INFO] [stdout]   --> src/advent23_3.rs:34:21
[INFO] [stdout]    |
[INFO] [stdout] 34 |                 if !v.is_digit(10) && !v.eq(&'.') {
[INFO] [stdout]    |                     ^^^^^^^^^^^^^^ help: try: `v.is_ascii_digit()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#is_digit_ascii_radix
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression creates a reference which is immediately dereferenced by the compiler
[INFO] [stdout]   --> src/advent23_3.rs:44:42
[INFO] [stdout]    |
[INFO] [stdout] 44 |     if let (Some(v), Some(r)) = (get_map(&map, x, y), get_map(&map, x + 1, y)) {
[INFO] [stdout]    |                                          ^^^^ help: change this to: `map`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression creates a reference which is immediately dereferenced by the compiler
[INFO] [stdout]   --> src/advent23_3.rs:44:63
[INFO] [stdout]    |
[INFO] [stdout] 44 |     if let (Some(v), Some(r)) = (get_map(&map, x, y), get_map(&map, x + 1, y)) {
[INFO] [stdout]    |                                                               ^^^^ help: change this to: `map`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of `char::is_digit` with literal radix of 10
[INFO] [stdout]   --> src/advent23_3.rs:45:12
[INFO] [stdout]    |
[INFO] [stdout] 45 |         if v.is_digit(10) && !r.is_digit(10) {
[INFO] [stdout]    |            ^^^^^^^^^^^^^^ help: try: `v.is_ascii_digit()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#is_digit_ascii_radix
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of `char::is_digit` with literal radix of 10
[INFO] [stdout]   --> src/advent23_3.rs:45:31
[INFO] [stdout]    |
[INFO] [stdout] 45 |         if v.is_digit(10) && !r.is_digit(10) {
[INFO] [stdout]    |                               ^^^^^^^^^^^^^^ help: try: `r.is_ascii_digit()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#is_digit_ascii_radix
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression creates a reference which is immediately dereferenced by the compiler
[INFO] [stdout]   --> src/advent23_3.rs:46:35
[INFO] [stdout]    |
[INFO] [stdout] 46 |             let value = get_value(&map, x, y);
[INFO] [stdout]    |                                   ^^^^ help: change this to: `map`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression creates a reference which is immediately dereferenced by the compiler
[INFO] [stdout]   --> src/advent23_3.rs:48:55
[INFO] [stdout]    |
[INFO] [stdout] 48 |             if let Some((part, x, y)) = close_to_part(&map, x, y, valueLen) {
[INFO] [stdout]    |                                                       ^^^^ help: change this to: `map`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this `.fold` can be written more succinctly using another method
[INFO] [stdout]   --> src/advent23_3.rs:81:35
[INFO] [stdout]    |
[INFO] [stdout] 81 |             let m = values.iter().fold(1, |acc, x| acc * x);
[INFO] [stdout]    |                                   ^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `product::<u32>()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unnecessary_fold
[INFO] [stdout]    = note: `#[warn(clippy::unnecessary_fold)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `valueLen` should have a snake case name
[INFO] [stdout]   --> src/advent23_3.rs:47:17
[INFO] [stdout]    |
[INFO] [stdout] 47 |             let valueLen = value.to_string().len();
[INFO] [stdout]    |                 ^^^^^^^^ help: convert the identifier to snake case: `value_len`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_snake_case)]` (part of `#[warn(nonstandard_style)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression borrows a value the compiler would automatically borrow
[INFO] [stdout]   --> src/advent23_4.rs:13:29
[INFO] [stdout]    |
[INFO] [stdout] 13 |         let match_nr: u32 = (&card[1]).parse().unwrap();
[INFO] [stdout]    |                             ^^^^^^^^^^ help: change this to: `card[1]`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout]    = note: `#[warn(clippy::needless_borrow)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression creates a reference which is immediately dereferenced by the compiler
[INFO] [stdout]   --> src/advent23_4.rs:17:84
[INFO] [stdout]    |
[INFO] [stdout] 17 |         let winning_numbers: Vec<u32> = numbers.iter().filter(|n| winners.contains(&n)).cloned().collect();
[INFO] [stdout]    |                                                                                    ^^ help: change this to: `n`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: length comparison to zero
[INFO] [stdout]   --> src/advent23_4.rs:20:12
[INFO] [stdout]    |
[INFO] [stdout] 20 |         if winning_numbers.len() > 0 {
[INFO] [stdout]    |            ^^^^^^^^^^^^^^^^^^^^^^^^^ help: using `!is_empty` is clearer and more explicit: `!winning_numbers.is_empty()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#len_zero
[INFO] [stdout]    = note: `#[warn(clippy::len_zero)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: iterating on a map's values
[INFO] [stdout]   --> src/advent23_4.rs:52:16
[INFO] [stdout]    |
[INFO] [stdout] 52 |     let sum2 = copies.iter().map(|(_match_nr, copy_nr)| copy_nr).sum::<u32>();
[INFO] [stdout]    |                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `copies.values()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#iter_kv_map
[INFO] [stdout]    = note: `#[warn(clippy::iter_kv_map)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression borrows a value the compiler would automatically borrow
[INFO] [stdout]   --> src/advent23_4.rs:13:29
[INFO] [stdout]    |
[INFO] [stdout] 13 |         let match_nr: u32 = (&card[1]).parse().unwrap();
[INFO] [stdout]    |                             ^^^^^^^^^^ help: change this to: `card[1]`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout]    = note: `#[warn(clippy::needless_borrow)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this expression creates a reference which is immediately dereferenced by the compiler
[INFO] [stdout]   --> src/advent23_4.rs:17:84
[INFO] [stdout]    |
[INFO] [stdout] 17 |         let winning_numbers: Vec<u32> = numbers.iter().filter(|n| winners.contains(&n)).cloned().collect();
[INFO] [stdout]    |                                                                                    ^^ help: change this to: `n`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: length comparison to zero
[INFO] [stdout]   --> src/advent23_4.rs:20:12
[INFO] [stdout]    |
[INFO] [stdout] 20 |         if winning_numbers.len() > 0 {
[INFO] [stdout]    |            ^^^^^^^^^^^^^^^^^^^^^^^^^ help: using `!is_empty` is clearer and more explicit: `!winning_numbers.is_empty()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#len_zero
[INFO] [stdout]    = note: `#[warn(clippy::len_zero)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: iterating on a map's values
[INFO] [stdout]   --> src/advent23_4.rs:52:16
[INFO] [stdout]    |
[INFO] [stdout] 52 |     let sum2 = copies.iter().map(|(_match_nr, copy_nr)| copy_nr).sum::<u32>();
[INFO] [stdout]    |                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `copies.values()`
[INFO] [stdout]    |
[INFO] [stdout]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#iter_kv_map
[INFO] [stdout]    = note: `#[warn(clippy::iter_kv_map)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 4.81s
[INFO] running `Command { std: "docker" "inspect" "9ae38e281e34d0f56c76f66412a67a54131032f123a05c1545aa5a810439afd0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9ae38e281e34d0f56c76f66412a67a54131032f123a05c1545aa5a810439afd0", kill_on_drop: false }`
[INFO] [stdout] 9ae38e281e34d0f56c76f66412a67a54131032f123a05c1545aa5a810439afd0