[INFO] cloning repository https://github.com/ShadowLightMan/bayes-classifier-in-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/ShadowLightMan/bayes-classifier-in-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FShadowLightMan%2Fbayes-classifier-in-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FShadowLightMan%2Fbayes-classifier-in-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] af9a714350375e1c7698f3fb086d537e671705c9
[INFO] checking ShadowLightMan/bayes-classifier-in-rust against master#bca37a20bd376ce3fd138e7cdee7fe704e0f8814 for pr-139493-3
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FShadowLightMan%2Fbayes-classifier-in-rust" "/workspace/builds/worker-6-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/ShadowLightMan/bayes-classifier-in-rust
[INFO] finished tweaking git repo https://github.com/ShadowLightMan/bayes-classifier-in-rust
[INFO] tweaked toml for git repo https://github.com/ShadowLightMan/bayes-classifier-in-rust written to /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/ShadowLightMan/bayes-classifier-in-rust on toolchain bca37a20bd376ce3fd138e7cdee7fe704e0f8814
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+bca37a20bd376ce3fd138e7cdee7fe704e0f8814" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/ShadowLightMan/bayes-classifier-in-rust 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" "+bca37a20bd376ce3fd138e7cdee7fe704e0f8814" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded csv-core v0.1.6
[INFO] [stderr]   Downloaded regex-automata v0.1.8
[INFO] [stderr]   Downloaded bstr v0.2.8
[INFO] [stderr]   Downloaded csv v1.1.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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:aa71247004a7fa38d13ec170f48f06cdedf5bc50b2a8645e56ed7e992e6fa513" "/opt/rustwide/cargo-home/bin/cargo" "+bca37a20bd376ce3fd138e7cdee7fe704e0f8814" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a0ad0fe36a9e94635e2afbca6ef2af2a46598d685828dfb9488a3c2723391972
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[INFO] running `Command { std: "docker" "rm" "-f" "a0ad0fe36a9e94635e2afbca6ef2af2a46598d685828dfb9488a3c2723391972", kill_on_drop: false }`
[INFO] [stdout] a0ad0fe36a9e94635e2afbca6ef2af2a46598d685828dfb9488a3c2723391972
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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:aa71247004a7fa38d13ec170f48f06cdedf5bc50b2a8645e56ed7e992e6fa513" "/opt/rustwide/cargo-home/bin/cargo" "+bca37a20bd376ce3fd138e7cdee7fe704e0f8814" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 34905bd5f9e6d7b14b421ed8c3d59073ca37a6557fc8e054f398d8431b6345d8
[INFO] running `Command { std: "docker" "start" "-a" "34905bd5f9e6d7b14b421ed8c3d59073ca37a6557fc8e054f398d8431b6345d8", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.65
[INFO] [stderr]    Compiling memchr v2.2.1
[INFO] [stderr]    Compiling byteorder v1.3.2
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]    Compiling serde v1.0.102
[INFO] [stderr]    Compiling ryu v1.0.2
[INFO] [stderr]     Checking itoa v0.4.4
[INFO] [stderr]     Checking regex-syntax v0.6.12
[INFO] [stderr]     Checking thread_local v0.3.6
[INFO] [stderr]     Checking regex-automata v0.1.8
[INFO] [stderr]     Checking aho-corasick v0.7.6
[INFO] [stderr]     Checking csv-core v0.1.6
[INFO] [stderr]     Checking regex v1.3.1
[INFO] [stderr]     Checking bstr v0.2.8
[INFO] [stderr]     Checking csv v1.1.1
[INFO] [stderr]     Checking bayes-classifier-in-rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::collections::hash_map::RandomState`
[INFO] [stdout]  --> src/train.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::collections::hash_map::RandomState;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::collections::hash_map::RandomState`
[INFO] [stdout]  --> src/train.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::collections::hash_map::RandomState;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/classify.rs:25:9
[INFO] [stdout]    |
[INFO] [stdout] 25 |     let mut posterior_probability = compute_posterior_probability(&review_count_by_class, overall_reviews_count); // P(c) = |Dc|/|D|
[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/classify.rs:27:9
[INFO] [stdout]    |
[INFO] [stdout] 27 |     let mut prior_probability = compute_prior_probability(
[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]   --> src/classify.rs:25:9
[INFO] [stdout]    |
[INFO] [stdout] 25 |     let mut posterior_probability = compute_posterior_probability(&review_count_by_class, overall_reviews_count); // P(c) = |Dc|/|D|
[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/classify.rs:27:9
[INFO] [stdout]    |
[INFO] [stdout] 27 |     let mut prior_probability = compute_prior_probability(
[INFO] [stdout]    |         ----^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `class_name`
[INFO] [stdout]    --> src/classify.rs:108:10
[INFO] [stdout]     |
[INFO] [stdout] 108 |     for (class_name, reviews_count) in review_count_by_class.iter().enumerate() {
[INFO] [stdout]     |          ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_class_name`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/classify.rs:144:9
[INFO] [stdout]     |
[INFO] [stdout] 144 |     let mut max_value = v.iter().fold(v[0], |mut max, &val| {
[INFO] [stdout]     |         ----^^^^^^^^^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `class_name`
[INFO] [stdout]    --> src/classify.rs:108:10
[INFO] [stdout]     |
[INFO] [stdout] 108 |     for (class_name, reviews_count) in review_count_by_class.iter().enumerate() {
[INFO] [stdout]     |          ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_class_name`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/classify.rs:144:9
[INFO] [stdout]     |
[INFO] [stdout] 144 |     let mut max_value = v.iter().fold(v[0], |mut max, &val| {
[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]   --> src/train.rs:14:9
[INFO] [stdout]    |
[INFO] [stdout] 14 |     let mut classes = read_reviews(content_dir).unwrap();
[INFO] [stdout]    |         ----^^^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `class`
[INFO] [stdout]   --> src/train.rs:25:10
[INFO] [stdout]    |
[INFO] [stdout] 25 |     for (class, reviews) in joined_reviews.iter().enumerate() {
[INFO] [stdout]    |          ^^^^^ help: if this is intentional, prefix it with an underscore: `_class`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/train.rs:14:9
[INFO] [stdout]    |
[INFO] [stdout] 14 |     let mut classes = read_reviews(content_dir).unwrap();
[INFO] [stdout]    |         ----^^^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `class`
[INFO] [stdout]   --> src/train.rs:25:10
[INFO] [stdout]    |
[INFO] [stdout] 25 |     for (class, reviews) in joined_reviews.iter().enumerate() {
[INFO] [stdout]    |          ^^^^^ help: if this is intentional, prefix it with an underscore: `_class`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:12:9
[INFO] [stdout]    |
[INFO] [stdout] 12 |         train::train(&args[2]);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 12 |         let _ = train::train(&args[2]);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:14:9
[INFO] [stdout]    |
[INFO] [stdout] 14 |         classify::classify(&args[2], &args[3]);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 14 |         let _ = classify::classify(&args[2], &args[3]);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]   --> src/utils.rs:16:28
[INFO] [stdout]    |
[INFO] [stdout] 16 | pub fn compile_regex(text: &str) -> Cow<str> {
[INFO] [stdout]    |                            ^^^^     ^^^^^^^^ the same lifetime is hidden here
[INFO] [stdout]    |                            |
[INFO] [stdout]    |                            the lifetime is elided here
[INFO] [stdout]    |
[INFO] [stdout]    = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout]    = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]    |
[INFO] [stdout] 16 | pub fn compile_regex(text: &str) -> Cow<'_, str> {
[INFO] [stdout]    |                                         +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/train.rs:37:5
[INFO] [stdout]    |
[INFO] [stdout] 37 |     writer.write_record(&["class", "word", "count"]);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 37 |     let _ = writer.write_record(&["class", "word", "count"]);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/train.rs:41:13
[INFO] [stdout]    |
[INFO] [stdout] 41 |             writer.write_record(&[&class_name.to_string(), &word, &occurrences.to_string()]);
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 41 |             let _ = writer.write_record(&[&class_name.to_string(), &word, &occurrences.to_string()]);
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/train.rs:48:5
[INFO] [stdout]    |
[INFO] [stdout] 48 |     writer.write_record(&["class", "count"]);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 48 |     let _ = writer.write_record(&["class", "count"]);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/train.rs:55:9
[INFO] [stdout]    |
[INFO] [stdout] 55 |         writer.write_record(&[&class_name.to_string(), &count.to_string()]);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 55 |         let _ = writer.write_record(&[&class_name.to_string(), &count.to_string()]);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/train.rs:67:5
[INFO] [stdout]    |
[INFO] [stdout] 67 |     writer.write_record(&["class", "count"]);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 67 |     let _ = writer.write_record(&["class", "count"]);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/train.rs:70:9
[INFO] [stdout]    |
[INFO] [stdout] 70 |         writer.write_record(&[&class_name.to_string(), &class_reviews.len().to_string()]);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 70 |         let _ = writer.write_record(&[&class_name.to_string(), &class_reviews.len().to_string()]);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:12:9
[INFO] [stdout]    |
[INFO] [stdout] 12 |         train::train(&args[2]);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 12 |         let _ = train::train(&args[2]);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:14:9
[INFO] [stdout]    |
[INFO] [stdout] 14 |         classify::classify(&args[2], &args[3]);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 14 |         let _ = classify::classify(&args[2], &args[3]);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]   --> src/utils.rs:16:28
[INFO] [stdout]    |
[INFO] [stdout] 16 | pub fn compile_regex(text: &str) -> Cow<str> {
[INFO] [stdout]    |                            ^^^^     ^^^^^^^^ the same lifetime is hidden here
[INFO] [stdout]    |                            |
[INFO] [stdout]    |                            the lifetime is elided here
[INFO] [stdout]    |
[INFO] [stdout]    = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout]    = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]    |
[INFO] [stdout] 16 | pub fn compile_regex(text: &str) -> Cow<'_, str> {
[INFO] [stdout]    |                                         +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/train.rs:37:5
[INFO] [stdout]    |
[INFO] [stdout] 37 |     writer.write_record(&["class", "word", "count"]);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 37 |     let _ = writer.write_record(&["class", "word", "count"]);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/train.rs:41:13
[INFO] [stdout]    |
[INFO] [stdout] 41 |             writer.write_record(&[&class_name.to_string(), &word, &occurrences.to_string()]);
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 41 |             let _ = writer.write_record(&[&class_name.to_string(), &word, &occurrences.to_string()]);
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/train.rs:48:5
[INFO] [stdout]    |
[INFO] [stdout] 48 |     writer.write_record(&["class", "count"]);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 48 |     let _ = writer.write_record(&["class", "count"]);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/train.rs:55:9
[INFO] [stdout]    |
[INFO] [stdout] 55 |         writer.write_record(&[&class_name.to_string(), &count.to_string()]);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 55 |         let _ = writer.write_record(&[&class_name.to_string(), &count.to_string()]);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/train.rs:67:5
[INFO] [stdout]    |
[INFO] [stdout] 67 |     writer.write_record(&["class", "count"]);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 67 |     let _ = writer.write_record(&["class", "count"]);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/train.rs:70:9
[INFO] [stdout]    |
[INFO] [stdout] 70 |         writer.write_record(&[&class_name.to_string(), &class_reviews.len().to_string()]);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 70 |         let _ = writer.write_record(&[&class_name.to_string(), &class_reviews.len().to_string()]);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [optimized + debuginfo] target(s) in 6.66s
[INFO] running `Command { std: "docker" "inspect" "34905bd5f9e6d7b14b421ed8c3d59073ca37a6557fc8e054f398d8431b6345d8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "34905bd5f9e6d7b14b421ed8c3d59073ca37a6557fc8e054f398d8431b6345d8", kill_on_drop: false }`
[INFO] [stdout] 34905bd5f9e6d7b14b421ed8c3d59073ca37a6557fc8e054f398d8431b6345d8
