[INFO] crate linear_solver 0.2.0 is already in cache [INFO] extracting crate linear_solver 0.2.0 into work/ex/clippy-test-run/sources/stable/reg/linear_solver/0.2.0 [INFO] extracting crate linear_solver 0.2.0 into work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/reg/linear_solver/0.2.0 [INFO] validating manifest of linear_solver-0.2.0 on toolchain stable [INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "read-manifest" "--manifest-path" "Cargo.toml"` [INFO] validating manifest of linear_solver-0.2.0 on toolchain stable+rustflags=-Dclippy::into_iter_on_array [INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "read-manifest" "--manifest-path" "Cargo.toml"` [INFO] started frobbing linear_solver-0.2.0 [INFO] finished frobbing linear_solver-0.2.0 [INFO] frobbed toml for linear_solver-0.2.0 written to work/ex/clippy-test-run/sources/stable/reg/linear_solver/0.2.0/Cargo.toml [INFO] started frobbing linear_solver-0.2.0 [INFO] finished frobbing linear_solver-0.2.0 [INFO] frobbed toml for linear_solver-0.2.0 written to work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/reg/linear_solver/0.2.0/Cargo.toml [INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"` [INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"` [INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "fetch" "--locked" "--manifest-path" "Cargo.toml"` [INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "fetch" "--locked" "--manifest-path" "Cargo.toml"` [INFO] linting linear_solver-0.2.0 against stable for clippy-test-run [INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/clippy-test-run/worker-4/stable:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/clippy-test-run/sources/stable/reg/linear_solver/0.2.0:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+stable" "clippy" "--frozen" "--all" "--all-targets"` [INFO] [stdout] 5c427bfe15db5107edf4e4e03bc13e3eecec8c2d129187e140b060e3e0f8057a [INFO] running `"docker" "start" "-a" "5c427bfe15db5107edf4e4e03bc13e3eecec8c2d129187e140b060e3e0f8057a"` [INFO] [stderr] Checking linear_solver v0.2.0 (/opt/crater/workdir) [INFO] [stderr] warning: long literal lacking separators [INFO] [stderr] --> src/lib.rs:405:31 [INFO] [stderr] | [INFO] [stderr] 405 | let false_positive_rate = 0.00000001; [INFO] [stderr] | ^^^^^^^^^^ help: consider: `0.000_000_01` [INFO] [stderr] | [INFO] [stderr] = note: #[warn(clippy::unreadable_literal)] on by default [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unreadable_literal [INFO] [stderr] [INFO] [stderr] warning: long literal lacking separators [INFO] [stderr] --> src/lib.rs:406:30 [INFO] [stderr] | [INFO] [stderr] 406 | let expected_num_items = 1000000000; [INFO] [stderr] | ^^^^^^^^^^ help: consider: `1_000_000_000` [INFO] [stderr] | [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unreadable_literal [INFO] [stderr] [INFO] [stderr] warning: parameter of type `HashSet` should be generalized over different hashers [INFO] [stderr] --> src/lib.rs:370:23 [INFO] [stderr] | [INFO] [stderr] 370 | infer: fn(cache: &HashSet, &[T]) -> Option> [INFO] [stderr] | ^^^^^^^^^^ [INFO] [stderr] | [INFO] [stderr] = note: #[warn(clippy::implicit_hasher)] on by default [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#implicit_hasher [INFO] [stderr] help: consider adding a type parameter [INFO] [stderr] | [INFO] [stderr] 368 | pub fn solve_minimum( [INFO] [stderr] 369 | mut facts: Vec, [INFO] [stderr] 370 | infer: fn(cache: &HashSet, &[T]) -> Option> [INFO] [stderr] | [INFO] [stderr] warning: long literal lacking separators [INFO] [stderr] --> src/lib.rs:405:31 [INFO] [stderr] | [INFO] [stderr] 405 | let false_positive_rate = 0.00000001; [INFO] [stderr] | ^^^^^^^^^^ help: consider: `0.000_000_01` [INFO] [stderr] | [INFO] [stderr] = note: #[warn(clippy::unreadable_literal)] on by default [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unreadable_literal [INFO] [stderr] [INFO] [stderr] warning: long literal lacking separators [INFO] [stderr] --> src/lib.rs:406:30 [INFO] [stderr] | [INFO] [stderr] 406 | let expected_num_items = 1000000000; [INFO] [stderr] | ^^^^^^^^^^ help: consider: `1_000_000_000` [INFO] [stderr] | [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unreadable_literal [INFO] [stderr] [INFO] [stderr] help: ...and use generic constructor [INFO] [stderr] | [INFO] [stderr] 397 | let mut cache = HashSet::default(); [INFO] [stderr] | ^^^^^^^^^^^^^^^^^^ [INFO] [stderr] [INFO] [stderr] warning: parameter of type `HashSet` should be generalized over different hashers [INFO] [stderr] --> src/lib.rs:370:23 [INFO] [stderr] | [INFO] [stderr] 370 | infer: fn(cache: &HashSet, &[T]) -> Option> [INFO] [stderr] | ^^^^^^^^^^ [INFO] [stderr] | [INFO] [stderr] = note: #[warn(clippy::implicit_hasher)] on by default [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#implicit_hasher [INFO] [stderr] help: consider adding a type parameter [INFO] [stderr] | [INFO] [stderr] 368 | pub fn solve_minimum( [INFO] [stderr] 369 | mut facts: Vec, [INFO] [stderr] 370 | infer: fn(cache: &HashSet, &[T]) -> Option> [INFO] [stderr] | [INFO] [stderr] help: ...and use generic constructor [INFO] [stderr] | [INFO] [stderr] 397 | let mut cache = HashSet::default(); [INFO] [stderr] | ^^^^^^^^^^^^^^^^^^ [INFO] [stderr] [INFO] [stderr] warning: this if statement can be collapsed [INFO] [stderr] --> examples/magic_square.rs:153:21 [INFO] [stderr] | [INFO] [stderr] 153 | / if vars[j] != var { [INFO] [stderr] 154 | | if rss[j] == rss[i] { [INFO] [stderr] 155 | | return Some(Propagate(False)); [INFO] [stderr] 156 | | } [INFO] [stderr] 157 | | } [INFO] [stderr] | |_____________________^ [INFO] [stderr] | [INFO] [stderr] = note: #[warn(clippy::collapsible_if)] on by default [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#collapsible_if [INFO] [stderr] help: try [INFO] [stderr] | [INFO] [stderr] 153 | if vars[j] != var && rss[j] == rss[i] { [INFO] [stderr] 154 | return Some(Propagate(False)); [INFO] [stderr] 155 | } [INFO] [stderr] | [INFO] [stderr] [INFO] [stderr] warning: parameter of type `HashSet` should be generalized over different hashers [INFO] [stderr] --> examples/le.rs:30:22 [INFO] [stderr] | [INFO] [stderr] 30 | pub fn infer(cache: &HashSet, facts: &[Expr]) -> Option> { [INFO] [stderr] | ^^^^^^^^^^^^^ [INFO] [stderr] | [INFO] [stderr] = note: #[warn(clippy::implicit_hasher)] on by default [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#implicit_hasher [INFO] [stderr] help: consider adding a type parameter [INFO] [stderr] | [INFO] [stderr] 30 | pub fn infer(cache: &HashSet, facts: &[Expr]) -> Option> { [INFO] [stderr] | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ^^^^^^^^^^^^^^^^ [INFO] [stderr] [INFO] [stderr] warning: the loop variable `i` is only used to index `res`. [INFO] [stderr] --> examples/le.rs:114:14 [INFO] [stderr] | [INFO] [stderr] 114 | for i in 0..res.len() { [INFO] [stderr] | ^^^^^^^^^^^^ [INFO] [stderr] | [INFO] [stderr] = note: #[warn(clippy::needless_range_loop)] on by default [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_range_loop [INFO] [stderr] help: consider using an iterator [INFO] [stderr] | [INFO] [stderr] 114 | for in &res { [INFO] [stderr] | ^^^^^^ ^^^^ [INFO] [stderr] [INFO] [stderr] warning: length comparison to zero [INFO] [stderr] --> examples/magic_square.rs:74:31 [INFO] [stderr] | [INFO] [stderr] 74 | } else if rs.len() == 0 {return Some((a, 0))} [INFO] [stderr] | ^^^^^^^^^^^^^ help: using `is_empty` is clearer and more explicit: `rs.is_empty()` [INFO] [stderr] | [INFO] [stderr] = note: #[warn(clippy::len_zero)] on by default [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#len_zero [INFO] [stderr] [INFO] [stderr] warning: parameter of type `HashSet` should be generalized over different hashers [INFO] [stderr] --> examples/magic_square.rs:82:22 [INFO] [stderr] | [INFO] [stderr] 82 | pub fn infer(cache: &HashSet, facts: &[Expr]) -> Option> { [INFO] [stderr] | ^^^^^^^^^^^^^ [INFO] [stderr] | [INFO] [stderr] = note: #[warn(clippy::implicit_hasher)] on by default [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#implicit_hasher [INFO] [stderr] help: consider adding a type parameter [INFO] [stderr] | [INFO] [stderr] 82 | pub fn infer(cache: &HashSet, facts: &[Expr]) -> Option> { [INFO] [stderr] | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ^^^^^^^^^^^^^^^^ [INFO] [stderr] [INFO] [stderr] warning: the function has a cyclomatic complexity of 95 [INFO] [stderr] --> examples/magic_square.rs:82:1 [INFO] [stderr] | [INFO] [stderr] 82 | / pub fn infer(cache: &HashSet, facts: &[Expr]) -> Option> { [INFO] [stderr] 83 | | if cache.contains(&False) {return None}; [INFO] [stderr] 84 | | [INFO] [stderr] 85 | | // Put simplification rules first to find simplest set of facts. [INFO] [stderr] ... | [INFO] [stderr] 398 | | None [INFO] [stderr] 399 | | } [INFO] [stderr] | |_^ [INFO] [stderr] | [INFO] [stderr] = note: #[warn(clippy::cyclomatic_complexity)] on by default [INFO] [stderr] = help: you could split it up into multiple smaller functions [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#cyclomatic_complexity [INFO] [stderr] [INFO] [stderr] warning: parameter of type `HashSet` should be generalized over different hashers [INFO] [stderr] --> examples/prime.rs:27:22 [INFO] [stderr] | [INFO] [stderr] 27 | pub fn infer(cache: &HashSet, facts: &[Expr]) -> Option> { [INFO] [stderr] | ^^^^^^^^^^^^^ [INFO] [stderr] | [INFO] [stderr] = note: #[warn(clippy::implicit_hasher)] on by default [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#implicit_hasher [INFO] [stderr] help: consider adding a type parameter [INFO] [stderr] | [INFO] [stderr] 27 | pub fn infer(cache: &HashSet, facts: &[Expr]) -> Option> { [INFO] [stderr] | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ^^^^^^^^^^^^^^^^ [INFO] [stderr] [INFO] [stderr] warning: you seem to be trying to use match for destructuring a single pattern. Consider using `if let` [INFO] [stderr] --> examples/prime.rs:34:21 [INFO] [stderr] | [INFO] [stderr] 34 | / match *eb { [INFO] [stderr] 35 | | Prime(j) => { [INFO] [stderr] 36 | | if i % j == 0 { [INFO] [stderr] 37 | | // Remove the number. [INFO] [stderr] ... | [INFO] [stderr] 41 | | _ => {} [INFO] [stderr] 42 | | } [INFO] [stderr] | |_____________________^ [INFO] [stderr] | [INFO] [stderr] = note: #[warn(clippy::single_match)] on by default [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#single_match [INFO] [stderr] help: try this [INFO] [stderr] | [INFO] [stderr] 34 | if let Prime(j) = *eb { [INFO] [stderr] 35 | if i % j == 0 { [INFO] [stderr] 36 | // Remove the number. [INFO] [stderr] 37 | return Some(OneTrue {from: ea.clone()}); [INFO] [stderr] 38 | } [INFO] [stderr] 39 | } [INFO] [stderr] | [INFO] [stderr] [INFO] [stderr] warning: length comparison to zero [INFO] [stderr] --> examples/magic_square.rs:186:24 [INFO] [stderr] | [INFO] [stderr] 186 | if rs.len() == 0 && ls.len() == 1 { [INFO] [stderr] | ^^^^^^^^^^^^^ help: using `is_empty` is clearer and more explicit: `rs.is_empty()` [INFO] [stderr] | [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#len_zero [INFO] [stderr] [INFO] [stderr] warning: length comparison to zero [INFO] [stderr] --> examples/magic_square.rs:198:24 [INFO] [stderr] | [INFO] [stderr] 198 | if rs.len() == 0 && ls.len() == 2 { [INFO] [stderr] | ^^^^^^^^^^^^^ help: using `is_empty` is clearer and more explicit: `rs.is_empty()` [INFO] [stderr] | [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#len_zero [INFO] [stderr] [INFO] [stderr] warning: the loop variable `i` is only used to index `ls`. [INFO] [stderr] --> examples/magic_square.rs:214:30 [INFO] [stderr] | [INFO] [stderr] 214 | for i in 0..ls.len() { [INFO] [stderr] | ^^^^^^^^^^^ [INFO] [stderr] | [INFO] [stderr] = note: #[warn(clippy::needless_range_loop)] on by default [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_range_loop [INFO] [stderr] help: consider using an iterator [INFO] [stderr] | [INFO] [stderr] 214 | for in &ls { [INFO] [stderr] | ^^^^^^ ^^^ [INFO] [stderr] [INFO] [stderr] warning: the loop variable `i` is only used to index `ls`. [INFO] [stderr] --> examples/magic_square.rs:222:34 [INFO] [stderr] | [INFO] [stderr] 222 | for i in 0..ls.len() { [INFO] [stderr] | ^^^^^^^^^^^ [INFO] [stderr] | [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_range_loop [INFO] [stderr] help: consider using an iterator [INFO] [stderr] | [INFO] [stderr] 222 | for in &ls { [INFO] [stderr] | ^^^^^^ ^^^ [INFO] [stderr] [INFO] [stderr] warning: the loop variable `k` is used to index `ls` [INFO] [stderr] --> examples/magic_square.rs:242:42 [INFO] [stderr] | [INFO] [stderr] 242 | for k in 0..ls.len() { [INFO] [stderr] | ^^^^^^^^^^^ [INFO] [stderr] | [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_range_loop [INFO] [stderr] help: consider using an iterator [INFO] [stderr] | [INFO] [stderr] 242 | for (k, ) in ls.iter().enumerate() { [INFO] [stderr] | ^^^^^^^^^^^ ^^^^^^^^^^^^^^^^^^^^^ [INFO] [stderr] [INFO] [stderr] warning: the loop variable `k` is used to index `rs` [INFO] [stderr] --> examples/magic_square.rs:246:42 [INFO] [stderr] | [INFO] [stderr] 246 | for k in 0..rs.len() { [INFO] [stderr] | ^^^^^^^^^^^ [INFO] [stderr] | [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_range_loop [INFO] [stderr] help: consider using an iterator [INFO] [stderr] | [INFO] [stderr] 246 | for (k, ) in rs.iter().enumerate() { [INFO] [stderr] | ^^^^^^^^^^^ ^^^^^^^^^^^^^^^^^^^^^ [INFO] [stderr] [INFO] [stderr] warning: the loop variable `i` is only used to index `res`. [INFO] [stderr] --> examples/prime.rs:65:14 [INFO] [stderr] | [INFO] [stderr] 65 | for i in 0..res.len() { [INFO] [stderr] | ^^^^^^^^^^^^ [INFO] [stderr] | [INFO] [stderr] = note: #[warn(clippy::needless_range_loop)] on by default [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_range_loop [INFO] [stderr] help: consider using an iterator [INFO] [stderr] | [INFO] [stderr] 65 | for in &res { [INFO] [stderr] | ^^^^^^ ^^^^ [INFO] [stderr] [INFO] [stderr] warning: the loop variable `k` is used to index `ls` [INFO] [stderr] --> examples/magic_square.rs:295:42 [INFO] [stderr] | [INFO] [stderr] 295 | for k in 0..ls.len() { [INFO] [stderr] | ^^^^^^^^^^^ [INFO] [stderr] | [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_range_loop [INFO] [stderr] help: consider using an iterator [INFO] [stderr] | [INFO] [stderr] 295 | for (k, ) in ls.iter().enumerate() { [INFO] [stderr] | ^^^^^^^^^^^ ^^^^^^^^^^^^^^^^^^^^^ [INFO] [stderr] [INFO] [stderr] warning: the loop variable `k` is used to index `rs` [INFO] [stderr] --> examples/magic_square.rs:304:42 [INFO] [stderr] | [INFO] [stderr] 304 | for k in 0..rs.len() { [INFO] [stderr] | ^^^^^^^^^^^ [INFO] [stderr] | [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_range_loop [INFO] [stderr] help: consider using an iterator [INFO] [stderr] | [INFO] [stderr] 304 | for (k, ) in rs.iter().enumerate() { [INFO] [stderr] | ^^^^^^^^^^^ ^^^^^^^^^^^^^^^^^^^^^ [INFO] [stderr] [INFO] [stderr] warning: length comparison to zero [INFO] [stderr] --> examples/magic_square.rs:365:16 [INFO] [stderr] | [INFO] [stderr] 365 | if alternatives.len() == 0 { [INFO] [stderr] | ^^^^^^^^^^^^^^^^^^^^^^^ help: using `is_empty` is clearer and more explicit: `alternatives.is_empty()` [INFO] [stderr] | [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#len_zero [INFO] [stderr] [INFO] [stderr] warning: an inclusive range would be more readable [INFO] [stderr] --> examples/magic_square.rs:377:34 [INFO] [stderr] | [INFO] [stderr] 377 | for k in start..end+1 { [INFO] [stderr] | ^^^^^^^^^^^^ help: use: `start..=end` [INFO] [stderr] | [INFO] [stderr] = note: #[warn(clippy::range_plus_one)] on by default [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#range_plus_one [INFO] [stderr] [INFO] [stderr] warning: the loop variable `i` is only used to index `facts`. [INFO] [stderr] --> examples/magic_square.rs:379:38 [INFO] [stderr] | [INFO] [stderr] 379 | for i in 0..facts.len() { [INFO] [stderr] | ^^^^^^^^^^^^^^ [INFO] [stderr] | [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_range_loop [INFO] [stderr] help: consider using an iterator [INFO] [stderr] | [INFO] [stderr] 379 | for in &facts { [INFO] [stderr] | ^^^^^^ ^^^^^^ [INFO] [stderr] [INFO] [stderr] warning: the loop variable `i` is only used to index `res`. [INFO] [stderr] --> examples/magic_square.rs:501:14 [INFO] [stderr] | [INFO] [stderr] 501 | for i in 0..res.len() { [INFO] [stderr] | ^^^^^^^^^^^^ [INFO] [stderr] | [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_range_loop [INFO] [stderr] help: consider using an iterator [INFO] [stderr] | [INFO] [stderr] 501 | for in &res { [INFO] [stderr] | ^^^^^^ ^^^^ [INFO] [stderr] [INFO] [stderr] warning: parameter of type `HashSet` should be generalized over different hashers [INFO] [stderr] --> examples/walk.rs:28:22 [INFO] [stderr] | [INFO] [stderr] 28 | pub fn infer(cache: &HashSet, _facts: &[Expr]) -> Option> { [INFO] [stderr] | ^^^^^^^^^^^^^ [INFO] [stderr] | [INFO] [stderr] = note: #[warn(clippy::implicit_hasher)] on by default [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#implicit_hasher [INFO] [stderr] help: consider adding a type parameter [INFO] [stderr] | [INFO] [stderr] 28 | pub fn infer(cache: &HashSet, _facts: &[Expr]) -> Option> { [INFO] [stderr] | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ^^^^^^^^^^^^^^^^ [INFO] [stderr] [INFO] [stderr] warning: the loop variable `i` is only used to index `res`. [INFO] [stderr] --> examples/walk.rs:52:14 [INFO] [stderr] | [INFO] [stderr] 52 | for i in 0..res.len() { [INFO] [stderr] | ^^^^^^^^^^^^ [INFO] [stderr] | [INFO] [stderr] = note: #[warn(clippy::needless_range_loop)] on by default [INFO] [stderr] = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_range_loop [INFO] [stderr] help: consider using an iterator [INFO] [stderr] | [INFO] [stderr] 52 | for in &res { [INFO] [stderr] | ^^^^^^ ^^^^ [INFO] [stderr] [INFO] [stderr] Finished dev [unoptimized + debuginfo] target(s) in 2.52s [INFO] running `"docker" "inspect" "5c427bfe15db5107edf4e4e03bc13e3eecec8c2d129187e140b060e3e0f8057a"` [INFO] running `"docker" "rm" "-f" "5c427bfe15db5107edf4e4e03bc13e3eecec8c2d129187e140b060e3e0f8057a"` [INFO] [stdout] 5c427bfe15db5107edf4e4e03bc13e3eecec8c2d129187e140b060e3e0f8057a