[INFO] updating cached repository lucke84/playing_around_with_rust
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/lucke84/playing_around_with_rust
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/lucke84/playing_around_with_rust" "work/ex/clippy-test-run/sources/stable/gh/lucke84/playing_around_with_rust"`
[INFO] [stderr] Cloning into 'work/ex/clippy-test-run/sources/stable/gh/lucke84/playing_around_with_rust'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/lucke84/playing_around_with_rust" "work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/lucke84/playing_around_with_rust"`
[INFO] [stderr] Cloning into 'work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/lucke84/playing_around_with_rust'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 258cf4006127f9f86cf750b991e2051b64bf8a08
[INFO] sha for GitHub repo lucke84/playing_around_with_rust: 258cf4006127f9f86cf750b991e2051b64bf8a08
[INFO] validating manifest of lucke84/playing_around_with_rust 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 lucke84/playing_around_with_rust 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 lucke84/playing_around_with_rust
[INFO] finished frobbing lucke84/playing_around_with_rust
[INFO] frobbed toml for lucke84/playing_around_with_rust written to work/ex/clippy-test-run/sources/stable/gh/lucke84/playing_around_with_rust/Cargo.toml
[INFO] started frobbing lucke84/playing_around_with_rust
[INFO] finished frobbing lucke84/playing_around_with_rust
[INFO] frobbed toml for lucke84/playing_around_with_rust written to work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/lucke84/playing_around_with_rust/Cargo.toml
[INFO] crate lucke84/playing_around_with_rust has a lockfile. skipping
[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 lucke84/playing_around_with_rust against stable for clippy-test-run
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/clippy-test-run/worker-7/stable:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/clippy-test-run/sources/stable/gh/lucke84/playing_around_with_rust:/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] d06a9bcfd47eb08903045a42c7f5dd5626c9f498521e944d5efb02cc2ed5c7c5
[INFO] running `"docker" "start" "-a" "d06a9bcfd47eb08903045a42c7f5dd5626c9f498521e944d5efb02cc2ed5c7c5"`
[INFO] [stderr]     Checking playing_around_with_rust v0.0.1 (/opt/crater/workdir)
[INFO] [stderr] warning: 5th binding whose name is just one char
[INFO] [stderr]   --> src/main.rs:12:9
[INFO] [stderr]    |
[INFO] [stderr] 12 |     let e: i32;
[INFO] [stderr]    |         ^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::many_single_char_names)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 6th binding whose name is just one char
[INFO] [stderr]   --> src/main.rs:18:13
[INFO] [stderr]    |
[INFO] [stderr] 18 |     let mut f = 5;                              // make variable mutable
[INFO] [stderr]    |             ^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 7th binding whose name is just one char
[INFO] [stderr]   --> src/main.rs:23:9
[INFO] [stderr]    |
[INFO] [stderr] 23 |     let g: i32 = 7;
[INFO] [stderr]    |         ^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 8th binding whose name is just one char
[INFO] [stderr]   --> src/main.rs:30:13
[INFO] [stderr]    |
[INFO] [stderr] 30 |         let h = 8;                              // h is not accessible outside of the scope of this block
[INFO] [stderr]    |             ^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 8th binding whose name is just one char
[INFO] [stderr]   --> src/main.rs:36:13
[INFO] [stderr]    |
[INFO] [stderr] 36 |     let mut i = 5;
[INFO] [stderr]    |             ^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 9th binding whose name is just one char
[INFO] [stderr]   --> src/main.rs:37:9
[INFO] [stderr]    |
[INFO] [stderr] 37 |     let j = (i = 6);                            // the value of an assignment is an empty tuple: so j has the value (), not 6
[INFO] [stderr]    |         ^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 10th binding whose name is just one char
[INFO] [stderr]   --> src/main.rs:39:9
[INFO] [stderr]    |
[INFO] [stderr] 39 |     let k = sum(i, 3);
[INFO] [stderr]    |         ^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 11th binding whose name is just one char
[INFO] [stderr]   --> src/main.rs:42:9
[INFO] [stderr]    |
[INFO] [stderr] 42 |     let l = always_return_one(999999);
[INFO] [stderr]    |         ^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 12th binding whose name is just one char
[INFO] [stderr]   --> src/main.rs:50:9
[INFO] [stderr]    |
[INFO] [stderr] 50 |     let n: fn(i32, i32) -> i32 = sum;                 // this is a function pointer (without inference)
[INFO] [stderr]    |         ^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 13th binding whose name is just one char
[INFO] [stderr]    --> src/main.rs:113:10
[INFO] [stderr]     |
[INFO] [stderr] 113 |     let (x, y) = tuple_xy;  // destructuring let 
[INFO] [stderr]     |          ^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 14th binding whose name is just one char
[INFO] [stderr]    --> src/main.rs:113:13
[INFO] [stderr]     |
[INFO] [stderr] 113 |     let (x, y) = tuple_xy;  // destructuring let 
[INFO] [stderr]     |             ^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 5th binding whose name is just one char
[INFO] [stderr]   --> src/main.rs:12:9
[INFO] [stderr]    |
[INFO] [stderr] 12 |     let e: i32;
[INFO] [stderr]    |         ^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::many_single_char_names)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 6th binding whose name is just one char
[INFO] [stderr]   --> src/main.rs:18:13
[INFO] [stderr]    |
[INFO] [stderr] 18 |     let mut f = 5;                              // make variable mutable
[INFO] [stderr]    |             ^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 7th binding whose name is just one char
[INFO] [stderr]   --> src/main.rs:23:9
[INFO] [stderr]    |
[INFO] [stderr] 23 |     let g: i32 = 7;
[INFO] [stderr]    |         ^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 8th binding whose name is just one char
[INFO] [stderr]   --> src/main.rs:30:13
[INFO] [stderr]    |
[INFO] [stderr] 30 |         let h = 8;                              // h is not accessible outside of the scope of this block
[INFO] [stderr]    |             ^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 8th binding whose name is just one char
[INFO] [stderr]   --> src/main.rs:36:13
[INFO] [stderr]    |
[INFO] [stderr] 36 |     let mut i = 5;
[INFO] [stderr]    |             ^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 9th binding whose name is just one char
[INFO] [stderr]   --> src/main.rs:37:9
[INFO] [stderr]    |
[INFO] [stderr] 37 |     let j = (i = 6);                            // the value of an assignment is an empty tuple: so j has the value (), not 6
[INFO] [stderr]    |         ^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 10th binding whose name is just one char
[INFO] [stderr]   --> src/main.rs:39:9
[INFO] [stderr]    |
[INFO] [stderr] 39 |     let k = sum(i, 3);
[INFO] [stderr]    |         ^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 11th binding whose name is just one char
[INFO] [stderr]   --> src/main.rs:42:9
[INFO] [stderr]    |
[INFO] [stderr] 42 |     let l = always_return_one(999999);
[INFO] [stderr]    |         ^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 12th binding whose name is just one char
[INFO] [stderr]   --> src/main.rs:50:9
[INFO] [stderr]    |
[INFO] [stderr] 50 |     let n: fn(i32, i32) -> i32 = sum;                 // this is a function pointer (without inference)
[INFO] [stderr]    |         ^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 13th binding whose name is just one char
[INFO] [stderr]    --> src/main.rs:113:10
[INFO] [stderr]     |
[INFO] [stderr] 113 |     let (x, y) = tuple_xy;  // destructuring let 
[INFO] [stderr]     |          ^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 14th binding whose name is just one char
[INFO] [stderr]    --> src/main.rs:113:13
[INFO] [stderr]     |
[INFO] [stderr] 113 |     let (x, y) = tuple_xy;  // destructuring let 
[INFO] [stderr]     |             ^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around assigned value
[INFO] [stderr]   --> src/main.rs:37:13
[INFO] [stderr]    |
[INFO] [stderr] 37 |     let j = (i = 6);                            // the value of an assignment is an empty tuple: so j has the value (), not 6
[INFO] [stderr]    |             ^^^^^^^ help: remove these parentheses
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_parens)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: long literal lacking separators
[INFO] [stderr]   --> src/main.rs:42:31
[INFO] [stderr]    |
[INFO] [stderr] 42 |     let l = always_return_one(999999);
[INFO] [stderr]    |                               ^^^^^^ help: consider: `999_999`
[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: unnecessary parentheses around assigned value
[INFO] [stderr]   --> src/main.rs:37:13
[INFO] [stderr]    |
[INFO] [stderr] 37 |     let j = (i = 6);                            // the value of an assignment is an empty tuple: so j has the value (), not 6
[INFO] [stderr]    |             ^^^^^^^ help: remove these parentheses
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_parens)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: long literal lacking separators
[INFO] [stderr]   --> src/main.rs:42:31
[INFO] [stderr]    |
[INFO] [stderr] 42 |     let l = always_return_one(999999);
[INFO] [stderr]    |                               ^^^^^^ help: consider: `999_999`
[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: unreachable expression
[INFO] [stderr]    --> src/main.rs:137:5
[INFO] [stderr]     |
[INFO] [stderr] 137 |     x                                           // never executed
[INFO] [stderr]     |     ^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unreachable_code)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `a`
[INFO] [stderr]  --> src/main.rs:7:9
[INFO] [stderr]   |
[INFO] [stderr] 7 |     let a = 1;                                  // type i32 is infered
[INFO] [stderr]   |         ^ help: consider using `_a` instead
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `b`
[INFO] [stderr]  --> src/main.rs:8:9
[INFO] [stderr]   |
[INFO] [stderr] 8 |     let b: i32 = 2;                             // type i32 is explicitly declared
[INFO] [stderr]   |         ^ help: consider using `_b` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `c`
[INFO] [stderr]   --> src/main.rs:10:10
[INFO] [stderr]    |
[INFO] [stderr] 10 |     let (c, d) = (3, 4);                        // variable bindings of multiple vars at the same time
[INFO] [stderr]    |          ^ help: consider using `_c` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `d`
[INFO] [stderr]   --> src/main.rs:10:13
[INFO] [stderr]    |
[INFO] [stderr] 10 |     let (c, d) = (3, 4);                        // variable bindings of multiple vars at the same time
[INFO] [stderr]    |             ^ help: consider using `_d` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `e`
[INFO] [stderr]   --> src/main.rs:12:9
[INFO] [stderr]    |
[INFO] [stderr] 12 |     let e: i32;
[INFO] [stderr]    |         ^ help: consider using `_e` instead
[INFO] [stderr] 
[INFO] [stderr] warning: variable `f` is assigned to, but never used
[INFO] [stderr]   --> src/main.rs:18:13
[INFO] [stderr]    |
[INFO] [stderr] 18 |     let mut f = 5;                              // make variable mutable
[INFO] [stderr]    |             ^
[INFO] [stderr]    |
[INFO] [stderr]    = note: consider using `_f` instead
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `f` is never read
[INFO] [stderr]   --> src/main.rs:19:5
[INFO] [stderr]    |
[INFO] [stderr] 19 |     f = 6;                                      // now I can assign a new value (of the same type!) to this variable
[INFO] [stderr]    |     ^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_assignments)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `f`
[INFO] [stderr]   --> src/main.rs:20:9
[INFO] [stderr]    |
[INFO] [stderr] 20 |     let f = "Look, I am text now";              // shadowing, and changing type!
[INFO] [stderr]    |         ^ help: consider using `_f` instead
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `i` is never read
[INFO] [stderr]   --> src/main.rs:36:13
[INFO] [stderr]    |
[INFO] [stderr] 36 |     let mut i = 5;
[INFO] [stderr]    |             ^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `j`
[INFO] [stderr]   --> src/main.rs:37:9
[INFO] [stderr]    |
[INFO] [stderr] 37 |     let j = (i = 6);                            // the value of an assignment is an empty tuple: so j has the value (), not 6
[INFO] [stderr]    |         ^ help: consider using `_j` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `a_boolean`
[INFO] [stderr]   --> src/main.rs:59:9
[INFO] [stderr]    |
[INFO] [stderr] 59 |     let a_boolean = true;                         // with inference
[INFO] [stderr]    |         ^^^^^^^^^ help: consider using `_a_boolean` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `another_boolean`
[INFO] [stderr]   --> src/main.rs:60:9
[INFO] [stderr]    |
[INFO] [stderr] 60 |     let another_boolean: bool = false;            // without inference
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^ help: consider using `_another_boolean` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `this_is_a_char`
[INFO] [stderr]   --> src/main.rs:63:9
[INFO] [stderr]    |
[INFO] [stderr] 63 |     let this_is_a_char = 'x';                    // delimited by a single quote/tick
[INFO] [stderr]    |         ^^^^^^^^^^^^^^ help: consider using `_this_is_a_char` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `two_hearts_char`
[INFO] [stderr]   --> src/main.rs:64:9
[INFO] [stderr]    |
[INFO] [stderr] 64 |     let two_hearts_char = '💕';                   // any unicode char (due to the fact that they are UTF-32, all chars are 4 bytes instead of just 1)
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^ help: consider using `_two_hearts_char` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `an_integer`
[INFO] [stderr]   --> src/main.rs:67:9
[INFO] [stderr]    |
[INFO] [stderr] 67 |     let an_integer = 42;                         // default with inference (type i32 - The 32-bit signed integer type)
[INFO] [stderr]    |         ^^^^^^^^^^ help: consider using `_an_integer` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `a_float`
[INFO] [stderr]   --> src/main.rs:68:9
[INFO] [stderr]    |
[INFO] [stderr] 68 |     let a_float = 1.0;                           // default with inference (type f64 - The 64-bit floating point type)
[INFO] [stderr]    |         ^^^^^^^ help: consider using `_a_float` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `complete_slice`
[INFO] [stderr]   --> src/main.rs:99:9
[INFO] [stderr]    |
[INFO] [stderr] 99 |     let complete_slice = &mutable_array[..];                  // [5, 7, 3, 23, 11]
[INFO] [stderr]    |         ^^^^^^^^^^^^^^ help: consider using `_complete_slice` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `partial_slice`
[INFO] [stderr]    --> src/main.rs:100:9
[INFO] [stderr]     |
[INFO] [stderr] 100 |     let partial_slice = &mutable_array[1..3];                 // [7, 4] - from item at index 1 to item at index 3 (excluded)
[INFO] [stderr]     |         ^^^^^^^^^^^^^ help: consider using `_partial_slice` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `from_item_till_end_slice`
[INFO] [stderr]    --> src/main.rs:101:9
[INFO] [stderr]     |
[INFO] [stderr] 101 |     let from_item_till_end_slice = &mutable_array[1..];       // [7, 4, 23, 11]
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using `_from_item_till_end_slice` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `from_beginning_till_item_slice`
[INFO] [stderr]    --> src/main.rs:102:9
[INFO] [stderr]     |
[INFO] [stderr] 102 |     let from_beginning_till_item_slice = &mutable_array[..2]; // [5, 7]
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using `_from_beginning_till_item_slice` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `tuple_one`
[INFO] [stderr]    --> src/main.rs:106:9
[INFO] [stderr]     |
[INFO] [stderr] 106 |     let tuple_one = (1, "one");
[INFO] [stderr]     |         ^^^^^^^^^ help: consider using `_tuple_one` instead
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `tuple_xy` is never read
[INFO] [stderr]    --> src/main.rs:110:13
[INFO] [stderr]     |
[INFO] [stderr] 110 |     let mut tuple_xy = (0, "zero");
[INFO] [stderr]     |             ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `tuple_second_item`
[INFO] [stderr]    --> src/main.rs:123:9
[INFO] [stderr]     |
[INFO] [stderr] 123 |     let tuple_second_item = tuple_xy.1;
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^ help: consider using `_tuple_second_item` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]    --> src/main.rs:135:22
[INFO] [stderr]     |
[INFO] [stderr] 135 | fn always_return_one(x: i32) -> i32 {
[INFO] [stderr]     |                      ^ help: consider using `_x` instead
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:87:9
[INFO] [stderr]    |
[INFO] [stderr] 87 |     let mut mutable_array = [1.5, 2.3, 3.0]; // type [f64; 3]
[INFO] [stderr]    |         ----^^^^^^^^^^^^^
[INFO] [stderr]    |         |
[INFO] [stderr]    |         help: remove this `mut`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_mut)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `diverges`
[INFO] [stderr]    --> src/main.rs:140:1
[INFO] [stderr]     |
[INFO] [stderr] 140 | fn diverges() -> ! {                            // defines the return type as "diverges" using the bang symbol
[INFO] [stderr]     | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(dead_code)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unreachable expression
[INFO] [stderr]    --> src/main.rs:137:5
[INFO] [stderr]     |
[INFO] [stderr] 137 |     x                                           // never executed
[INFO] [stderr]     |     ^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unreachable_code)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: this let-binding has unit value. Consider omitting `let j =`
[INFO] [stderr]   --> src/main.rs:37:5
[INFO] [stderr]    |
[INFO] [stderr] 37 |     let j = (i = 6);                            // the value of an assignment is an empty tuple: so j has the value (), not 6
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::let_unit_value)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#let_unit_value
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `a`
[INFO] [stderr]  --> src/main.rs:7:9
[INFO] [stderr]   |
[INFO] [stderr] 7 |     let a = 1;                                  // type i32 is infered
[INFO] [stderr]   |         ^ help: consider using `_a` instead
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `b`
[INFO] [stderr]  --> src/main.rs:8:9
[INFO] [stderr]   |
[INFO] [stderr] 8 |     let b: i32 = 2;                             // type i32 is explicitly declared
[INFO] [stderr]   |         ^ help: consider using `_b` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `c`
[INFO] [stderr]   --> src/main.rs:10:10
[INFO] [stderr]    |
[INFO] [stderr] 10 |     let (c, d) = (3, 4);                        // variable bindings of multiple vars at the same time
[INFO] [stderr]    |          ^ help: consider using `_c` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `d`
[INFO] [stderr]   --> src/main.rs:10:13
[INFO] [stderr]    |
[INFO] [stderr] 10 |     let (c, d) = (3, 4);                        // variable bindings of multiple vars at the same time
[INFO] [stderr]    |             ^ help: consider using `_d` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `e`
[INFO] [stderr]   --> src/main.rs:12:9
[INFO] [stderr]    |
[INFO] [stderr] 12 |     let e: i32;
[INFO] [stderr]    |         ^ help: consider using `_e` instead
[INFO] [stderr] 
[INFO] [stderr] warning: variable `f` is assigned to, but never used
[INFO] [stderr]   --> src/main.rs:18:13
[INFO] [stderr]    |
[INFO] [stderr] 18 |     let mut f = 5;                              // make variable mutable
[INFO] [stderr]    |             ^
[INFO] [stderr]    |
[INFO] [stderr]    = note: consider using `_f` instead
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `f` is never read
[INFO] [stderr]   --> src/main.rs:19:5
[INFO] [stderr]    |
[INFO] [stderr] 19 |     f = 6;                                      // now I can assign a new value (of the same type!) to this variable
[INFO] [stderr]    |     ^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_assignments)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `f`
[INFO] [stderr]   --> src/main.rs:20:9
[INFO] [stderr]    |
[INFO] [stderr] 20 |     let f = "Look, I am text now";              // shadowing, and changing type!
[INFO] [stderr]    |         ^ help: consider using `_f` instead
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `i` is never read
[INFO] [stderr]   --> src/main.rs:36:13
[INFO] [stderr]    |
[INFO] [stderr] 36 |     let mut i = 5;
[INFO] [stderr]    |             ^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `j`
[INFO] [stderr]   --> src/main.rs:37:9
[INFO] [stderr]    |
[INFO] [stderr] 37 |     let j = (i = 6);                            // the value of an assignment is an empty tuple: so j has the value (), not 6
[INFO] [stderr]    |         ^ help: consider using `_j` instead
[INFO] [stderr] 
[INFO] [stderr] warning: statement with no effect
[INFO] [stderr]    --> src/main.rs:118:5
[INFO] [stderr]     |
[INFO] [stderr] 118 |     (0,); // single-element tuple
[INFO] [stderr]     |     ^^^^^
[INFO] [stderr] warning: unused variable: `a_boolean`
[INFO] [stderr]   --> src/main.rs:59:9
[INFO] [stderr]    |
[INFO] [stderr] 59 |     let a_boolean = true;                         // with inference
[INFO] [stderr]    |         ^^^^^^^^^ help: consider using `_a_boolean` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `another_boolean`
[INFO] [stderr]   --> src/main.rs:60:9
[INFO] [stderr]    |
[INFO] [stderr] 60 |     let another_boolean: bool = false;            // without inference
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^ help: consider using `_another_boolean` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `this_is_a_char`
[INFO] [stderr]   --> src/main.rs:63:9
[INFO] [stderr]    |
[INFO] [stderr] 63 |     let this_is_a_char = 'x';                    // delimited by a single quote/tick
[INFO] [stderr]    |         ^^^^^^^^^^^^^^ help: consider using `_this_is_a_char` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `two_hearts_char`
[INFO] [stderr]   --> src/main.rs:64:9
[INFO] [stderr]    |
[INFO] [stderr] 64 |     let two_hearts_char = '💕';                   // any unicode char (due to the fact that they are UTF-32, all chars are 4 bytes instead of just 1)
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^ help: consider using `_two_hearts_char` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `an_integer`
[INFO] [stderr]   --> src/main.rs:67:9
[INFO] [stderr]    |
[INFO] [stderr] 67 |     let an_integer = 42;                         // default with inference (type i32 - The 32-bit signed integer type)
[INFO] [stderr]    |         ^^^^^^^^^^ help: consider using `_an_integer` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `a_float`
[INFO] [stderr]   --> src/main.rs:68:9
[INFO] [stderr]    |
[INFO] [stderr] 68 |     let a_float = 1.0;                           // default with inference (type f64 - The 64-bit floating point type)
[INFO] [stderr]    |         ^^^^^^^ help: consider using `_a_float` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `complete_slice`
[INFO] [stderr]   --> src/main.rs:99:9
[INFO] [stderr]    |
[INFO] [stderr] 99 |     let complete_slice = &mutable_array[..];                  // [5, 7, 3, 23, 11]
[INFO] [stderr]    |         ^^^^^^^^^^^^^^ help: consider using `_complete_slice` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `partial_slice`
[INFO] [stderr]    --> src/main.rs:100:9
[INFO] [stderr]     |
[INFO] [stderr] 100 |     let partial_slice = &mutable_array[1..3];                 // [7, 4] - from item at index 1 to item at index 3 (excluded)
[INFO] [stderr]     |         ^^^^^^^^^^^^^ help: consider using `_partial_slice` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `from_item_till_end_slice`
[INFO] [stderr]    --> src/main.rs:101:9
[INFO] [stderr]     |
[INFO] [stderr] 101 |     let from_item_till_end_slice = &mutable_array[1..];       // [7, 4, 23, 11]
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using `_from_item_till_end_slice` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `from_beginning_till_item_slice`
[INFO] [stderr]    --> src/main.rs:102:9
[INFO] [stderr]     |
[INFO] [stderr] 102 |     let from_beginning_till_item_slice = &mutable_array[..2]; // [5, 7]
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using `_from_beginning_till_item_slice` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `tuple_one`
[INFO] [stderr]    --> src/main.rs:106:9
[INFO] [stderr]     |
[INFO] [stderr] 106 |     let tuple_one = (1, "one");
[INFO] [stderr]     |         ^^^^^^^^^ help: consider using `_tuple_one` instead
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `tuple_xy` is never read
[INFO] [stderr]    --> src/main.rs:110:13
[INFO] [stderr]     |
[INFO] [stderr] 110 |     let mut tuple_xy = (0, "zero");
[INFO] [stderr]     |             ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `tuple_second_item`
[INFO] [stderr]    --> src/main.rs:123:9
[INFO] [stderr]     |
[INFO] [stderr] 123 |     let tuple_second_item = tuple_xy.1;
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^ help: consider using `_tuple_second_item` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]    --> src/main.rs:135:22
[INFO] [stderr]     |
[INFO] [stderr] 135 | fn always_return_one(x: i32) -> i32 {
[INFO] [stderr]     |                      ^ help: consider using `_x` instead
[INFO] [stderr] 
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::no_effect)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#no_effect
[INFO] [stderr] 
[INFO] [stderr] warning: statement with no effect
[INFO] [stderr]    --> src/main.rs:119:5
[INFO] [stderr]     |
[INFO] [stderr] 119 |     (0); // zero in parentheses
[INFO] [stderr]     |     ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#no_effect
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:87:9
[INFO] [stderr]    |
[INFO] [stderr] 87 |     let mut mutable_array = [1.5, 2.3, 3.0]; // type [f64; 3]
[INFO] [stderr]    |         ----^^^^^^^^^^^^^
[INFO] [stderr]    |         |
[INFO] [stderr]    |         help: remove this `mut`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_mut)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `diverges`
[INFO] [stderr]    --> src/main.rs:140:1
[INFO] [stderr]     |
[INFO] [stderr] 140 | fn diverges() -> ! {                            // defines the return type as "diverges" using the bang symbol
[INFO] [stderr]     | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(dead_code)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: this let-binding has unit value. Consider omitting `let j =`
[INFO] [stderr]   --> src/main.rs:37:5
[INFO] [stderr]    |
[INFO] [stderr] 37 |     let j = (i = 6);                            // the value of an assignment is an empty tuple: so j has the value (), not 6
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::let_unit_value)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#let_unit_value
[INFO] [stderr] 
[INFO] [stderr] warning: statement with no effect
[INFO] [stderr]    --> src/main.rs:118:5
[INFO] [stderr]     |
[INFO] [stderr] 118 |     (0,); // single-element tuple
[INFO] [stderr]     |     ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::no_effect)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#no_effect
[INFO] [stderr] 
[INFO] [stderr] warning: statement with no effect
[INFO] [stderr]    --> src/main.rs:119:5
[INFO] [stderr]     |
[INFO] [stderr] 119 |     (0); // zero in parentheses
[INFO] [stderr]     |     ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#no_effect
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.75s
[INFO] running `"docker" "inspect" "d06a9bcfd47eb08903045a42c7f5dd5626c9f498521e944d5efb02cc2ed5c7c5"`
[INFO] running `"docker" "rm" "-f" "d06a9bcfd47eb08903045a42c7f5dd5626c9f498521e944d5efb02cc2ed5c7c5"`
[INFO] [stdout] d06a9bcfd47eb08903045a42c7f5dd5626c9f498521e944d5efb02cc2ed5c7c5