error: for loop over `option`, which is an `Option`. This is more readably written as an `if let` statement. --> for_loop.rs:17:14 | 17 | for x in option { | ^^^^^^ | = note: `-D for-loop-over-option` implied by `-D warnings` = help: consider replacing `for x in option` with `if let Some(x) = option` error: for loop over `result`, which is a `Result`. This is more readably written as an `if let` statement. --> for_loop.rs:22:14 | 22 | for x in result { | ^^^^^^ | = note: `-D for-loop-over-result` implied by `-D warnings` = help: consider replacing `for x in result` with `if let Ok(x) = result` error: for loop over `option.ok_or("x not found")`, which is a `Result`. This is more readably written as an `if let` statement. --> for_loop.rs:26:14 | 26 | for x in option.ok_or("x not found") { | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ | = help: consider replacing `for x in option.ok_or("x not found")` with `if let Ok(x) = option.ok_or("x not found")` error: you are iterating over `Iterator::next()` which is an Option; this will compile but is probably not what you want --> for_loop.rs:31:5 | 31 | / for x in v.iter().next() { 32 | | println!("{}", x); 33 | | } | |_____^ | = note: `-D iter-next-loop` implied by `-D warnings` error: for loop over `v.iter().next().and(Some(0))`, which is an `Option`. This is more readably written as an `if let` statement. --> for_loop.rs:36:14 | 36 | for x in v.iter().next().and(Some(0)) { | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | = help: consider replacing `for x in v.iter().next().and(Some(0))` with `if let Some(x) = v.iter().next().and(Some(0))` error: for loop over `v.iter().next().ok_or("x not found")`, which is a `Result`. This is more readably written as an `if let` statement. --> for_loop.rs:40:14 | 40 | for x in v.iter().next().ok_or("x not found") { | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | = help: consider replacing `for x in v.iter().next().ok_or("x not found")` with `if let Ok(x) = v.iter().next().ok_or("x not found")` error: this loop never actually loops --> for_loop.rs:52:5 | 52 | / while let Some(x) = option { 53 | | println!("{}", x); 54 | | break; 55 | | } | |_____^ | = note: `-D never-loop` implied by `-D warnings` error: this loop never actually loops --> for_loop.rs:58:5 | 58 | / while let Ok(x) = result { 59 | | println!("{}", x); 60 | | break; 61 | | } | |_____^ error: the loop variable `i` is only used to index `vec`. --> for_loop.rs:84:5 | 84 | / for i in 0..vec.len() { 85 | | println!("{}", vec[i]); 86 | | } | |_____^ | = note: `-D needless-range-loop` implied by `-D warnings` help: consider using an iterator | 84 | for in &vec { | ^^^^^^ error: unused variable: `i` --> for_loop.rs:88:9 | 88 | for i in 0..vec.len() { | ^ | = note: `-D unused-variables` implied by `-D warnings` error: the loop variable `i` is only used to index `vec`. --> for_loop.rs:93:5 | 93 | for i in 0..vec.len() { let _ = vec[i]; } | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | help: consider using an iterator | 93 | for in &vec { let _ = vec[i]; } | ^^^^^^ error: the loop variable `j` is only used to index `STATIC`. --> for_loop.rs:96:5 | 96 | / for j in 0..4 { 97 | | println!("{:?}", STATIC[j]); 98 | | } | |_____^ | help: consider using an iterator | 96 | for in STATIC.iter().take(4) { | ^^^^^^ error: the loop variable `j` is only used to index `CONST`. --> for_loop.rs:100:5 | 100 | / for j in 0..4 { 101 | | println!("{:?}", CONST[j]); 102 | | } | |_____^ | help: consider using an iterator | 100 | for in CONST.iter().take(4) { | ^^^^^^ error: the loop variable `i` is used to index `vec` --> for_loop.rs:104:5 | 104 | / for i in 0..vec.len() { 105 | | println!("{} {}", vec[i], i); 106 | | } | |_____^ | help: consider using an iterator | 104 | for (i, ) in vec.iter().enumerate() { | ^^^^^^^^^^^ error: the loop variable `i` is only used to index `vec2`. --> for_loop.rs:111:5 | 111 | / for i in 0..vec.len() { 112 | | println!("{}", vec2[i]); 113 | | } | |_____^ | help: consider using an iterator | 111 | for in vec2.iter().take(vec.len()) { | ^^^^^^ error: the loop variable `i` is only used to index `vec`. --> for_loop.rs:115:5 | 115 | / for i in 5..vec.len() { 116 | | println!("{}", vec[i]); 117 | | } | |_____^ | help: consider using an iterator | 115 | for in vec.iter().skip(5) { | ^^^^^^ error: the loop variable `i` is only used to index `vec`. --> for_loop.rs:119:5 | 119 | / for i in 0..MAX_LEN { 120 | | println!("{}", vec[i]); 121 | | } | |_____^ | help: consider using an iterator | 119 | for in vec.iter().take(MAX_LEN) { | ^^^^^^ error: the loop variable `i` is only used to index `vec`. --> for_loop.rs:123:5 | 123 | / for i in 0...MAX_LEN { 124 | | println!("{}", vec[i]); 125 | | } | |_____^ | help: consider using an iterator | 123 | for in vec.iter().take(MAX_LEN + 1) { | ^^^^^^ error: the loop variable `i` is only used to index `vec`. --> for_loop.rs:127:5 | 127 | / for i in 5..10 { 128 | | println!("{}", vec[i]); 129 | | } | |_____^ | help: consider using an iterator | 127 | for in vec.iter().take(10).skip(5) { | ^^^^^^ error: the loop variable `i` is only used to index `vec`. --> for_loop.rs:131:5 | 131 | / for i in 5...10 { 132 | | println!("{}", vec[i]); 133 | | } | |_____^ | help: consider using an iterator | 131 | for in vec.iter().take(10 + 1).skip(5) { | ^^^^^^ error: the loop variable `i` is used to index `vec` --> for_loop.rs:135:5 | 135 | / for i in 5..vec.len() { 136 | | println!("{} {}", vec[i], i); 137 | | } | |_____^ | help: consider using an iterator | 135 | for (i, ) in vec.iter().enumerate().skip(5) { | ^^^^^^^^^^^ error: the loop variable `i` is used to index `vec` --> for_loop.rs:139:5 | 139 | / for i in 5..10 { 140 | | println!("{} {}", vec[i], i); 141 | | } | |_____^ | help: consider using an iterator | 139 | for (i, ) in vec.iter().enumerate().take(10).skip(5) { | ^^^^^^^^^^^ error: this range is empty so this for loop will never run --> for_loop.rs:143:5 | 143 | / for i in 10..0 { 144 | | println!("{}", i); 145 | | } | |_____^ | = note: `-D reverse-range-loop` implied by `-D warnings` help: consider using the following if you are attempting to iterate over this range in reverse | 143 | for i in (0..10).rev() { | ^^^^^^^^^^^^^ error: this range is empty so this for loop will never run --> for_loop.rs:147:5 | 147 | / for i in 10...0 { 148 | | println!("{}", i); 149 | | } | |_____^ | help: consider using the following if you are attempting to iterate over this range in reverse | 147 | for i in (0...10).rev() { | ^^^^^^^^^^^^^^ error: this range is empty so this for loop will never run --> for_loop.rs:151:5 | 151 | / for i in MAX_LEN..0 { 152 | | println!("{}", i); 153 | | } | |_____^ | help: consider using the following if you are attempting to iterate over this range in reverse | 151 | for i in (0..MAX_LEN).rev() { | ^^^^^^^^^^^^^^^^^^ error: this range is empty so this for loop will never run --> for_loop.rs:155:5 | 155 | / for i in 5..5 { 156 | | println!("{}", i); 157 | | } | |_____^ error: this range is empty so this for loop will never run --> for_loop.rs:176:5 | 176 | / for i in 10..5+4 { 177 | | println!("{}", i); 178 | | } | |_____^ | help: consider using the following if you are attempting to iterate over this range in reverse | 176 | for i in (5+4..10).rev() { | ^^^^^^^^^^^^^^^ error: this range is empty so this for loop will never run --> for_loop.rs:180:5 | 180 | / for i in (5+2)..(3-1) { 181 | | println!("{}", i); 182 | | } | |_____^ | help: consider using the following if you are attempting to iterate over this range in reverse | 180 | for i in ((3-1)..(5+2)).rev() { | ^^^^^^^^^^^^^^^^^^^^ error: this range is empty so this for loop will never run --> for_loop.rs:184:5 | 184 | / for i in (5+2)..(8-1) { 185 | | println!("{}", i); 186 | | } | |_____^ error: it is more idiomatic to loop over references to containers instead of using explicit iteration methods --> for_loop.rs:203:15 | 203 | for _v in vec.iter() { } | ^^^^^^^^^^ help: to write this more concisely, try: `&vec` | = note: `-D explicit-iter-loop` implied by `-D warnings` error: it is more idiomatic to loop over references to containers instead of using explicit iteration methods --> for_loop.rs:205:15 | 205 | for _v in vec.iter_mut() { } | ^^^^^^^^^^^^^^ help: to write this more concisely, try: `&mut vec` error: it is more idiomatic to loop over containers instead of using explicit iteration methods` --> for_loop.rs:208:15 | 208 | for _v in out_vec.into_iter() { } | ^^^^^^^^^^^^^^^^^^^ help: to write this more concisely, try: `out_vec` | = note: `-D explicit-into-iter-loop` implied by `-D warnings` error: it is more idiomatic to loop over references to containers instead of using explicit iteration methods --> for_loop.rs:211:15 | 211 | for _v in array.into_iter() {} | ^^^^^^^^^^^^^^^^^ help: to write this more concisely, try: `&array` error: it is more idiomatic to loop over references to containers instead of using explicit iteration methods --> for_loop.rs:216:15 | 216 | for _v in [1, 2, 3].iter() { } | ^^^^^^^^^^^^^^^^ help: to write this more concisely, try: `&[1, 2, 3]` error: it is more idiomatic to loop over references to containers instead of using explicit iteration methods --> for_loop.rs:220:15 | 220 | for _v in [0; 32].iter() {} | ^^^^^^^^^^^^^^ help: to write this more concisely, try: `&[0; 32]` error: it is more idiomatic to loop over references to containers instead of using explicit iteration methods --> for_loop.rs:225:15 | 225 | for _v in ll.iter() { } | ^^^^^^^^^ help: to write this more concisely, try: `&ll` error: it is more idiomatic to loop over references to containers instead of using explicit iteration methods --> for_loop.rs:228:15 | 228 | for _v in vd.iter() { } | ^^^^^^^^^ help: to write this more concisely, try: `&vd` error: it is more idiomatic to loop over references to containers instead of using explicit iteration methods --> for_loop.rs:231:15 | 231 | for _v in bh.iter() { } | ^^^^^^^^^ help: to write this more concisely, try: `&bh` error: it is more idiomatic to loop over references to containers instead of using explicit iteration methods --> for_loop.rs:234:15 | 234 | for _v in hm.iter() { } | ^^^^^^^^^ help: to write this more concisely, try: `&hm` error: it is more idiomatic to loop over references to containers instead of using explicit iteration methods --> for_loop.rs:237:15 | 237 | for _v in bt.iter() { } | ^^^^^^^^^ help: to write this more concisely, try: `&bt` error: it is more idiomatic to loop over references to containers instead of using explicit iteration methods --> for_loop.rs:240:15 | 240 | for _v in hs.iter() { } | ^^^^^^^^^ help: to write this more concisely, try: `&hs` error: it is more idiomatic to loop over references to containers instead of using explicit iteration methods --> for_loop.rs:243:15 | 243 | for _v in bs.iter() { } | ^^^^^^^^^ help: to write this more concisely, try: `&bs` error: you are iterating over `Iterator::next()` which is an Option; this will compile but is probably not what you want --> for_loop.rs:245:5 | 245 | for _v in vec.iter().next() { } | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: you are collect()ing an iterator and throwing away the result. Consider using an explicit for loop to exhaust the iterator --> for_loop.rs:252:5 | 252 | vec.iter().cloned().map(|x| out.push(x)).collect::>(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | = note: `-D unused-collect` implied by `-D warnings` error: the variable `_index` is used as a loop counter. Consider using `for (_index, item) in &vec.enumerate()` or similar iterators --> for_loop.rs:257:5 | 257 | for _v in &vec { _index += 1 } | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | = note: `-D explicit-counter-loop` implied by `-D warnings` error: the variable `_index` is used as a loop counter. Consider using `for (_index, item) in &vec.enumerate()` or similar iterators --> for_loop.rs:261:5 | 261 | for _v in &vec { _index += 1 } | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: you seem to want to iterate on a map's values --> for_loop.rs:321:5 | 321 | / for (_, v) in &m { 322 | | let _v = v; 323 | | } | |_____^ | = note: `-D for-kv-map` implied by `-D warnings` help: use the corresponding method | 321 | for v in m.values() { | ^ error: you seem to want to iterate on a map's values --> for_loop.rs:326:5 | 326 | / for (_, v) in &*m { 327 | | let _v = v; 328 | | // Here the `*` is not actually necesarry, but the test tests that we don't suggest 329 | | // `in *m.values()` as we used to 330 | | } | |_____^ | help: use the corresponding method | 326 | for v in (*m).values() { | ^ error: you seem to want to iterate on a map's values --> for_loop.rs:333:5 | 333 | / for (_, v) in &mut m { 334 | | let _v = v; 335 | | } | |_____^ | help: use the corresponding method | 333 | for v in m.values_mut() { | ^ error: you seem to want to iterate on a map's values --> for_loop.rs:338:5 | 338 | / for (_, v) in &mut *m { 339 | | let _v = v; 340 | | } | |_____^ | help: use the corresponding method | 338 | for v in (*m).values_mut() { | ^ error: you seem to want to iterate on a map's keys --> for_loop.rs:344:5 | 344 | / for (k, _value) in rm { 345 | | let _k = k; 346 | | } | |_____^ | help: use the corresponding method | 344 | for k in rm.keys() { | ^ error: aborting due to 51 previous errors To learn more, run the command again with --verbose.