[INFO] cloning repository https://github.com/benbenfan/reverse-polish-hanoi-calculator
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[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbenbenfan%2Freverse-polish-hanoi-calculator'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] b32568fbfd2f4efaef0313454d1f2ecce2974890
[INFO] checking benbenfan/reverse-polish-hanoi-calculator against try#21cad1f647cfd05a566220f933edd88a53e50bcf for pr-129249-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbenbenfan%2Freverse-polish-hanoi-calculator" "/workspace/builds/worker-5-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/benbenfan/reverse-polish-hanoi-calculator
[INFO] finished tweaking git repo https://github.com/benbenfan/reverse-polish-hanoi-calculator
[INFO] tweaked toml for git repo https://github.com/benbenfan/reverse-polish-hanoi-calculator written to /workspace/builds/worker-5-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/benbenfan/reverse-polish-hanoi-calculator on toolchain 21cad1f647cfd05a566220f933edd88a53e50bcf
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+21cad1f647cfd05a566220f933edd88a53e50bcf" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/benbenfan/reverse-polish-hanoi-calculator 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" "+21cad1f647cfd05a566220f933edd88a53e50bcf" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/target:/opt/rustwide/target:rw,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" "-m" "1610612736" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:3e793bdf10248eb2ddbd6b0faebed8155c11b4589982e2893733958d93e8d540" "sleep" "infinity", kill_on_drop: false }`
[INFO] [stdout] 03808d6c213cf9ce707c2ba0c946506b9108a3e68c0c8b1ead56389f90c0d273
[INFO] running `Command { std: "docker" "start" "03808d6c213cf9ce707c2ba0c946506b9108a3e68c0c8b1ead56389f90c0d273", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-w" "/opt/rustwide/workdir" "--user" "0:0" "03808d6c213cf9ce707c2ba0c946506b9108a3e68c0c8b1ead56389f90c0d273" "/opt/rustwide/cargo-home/bin/cargo" "+21cad1f647cfd05a566220f933edd88a53e50bcf" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "03808d6c213cf9ce707c2ba0c946506b9108a3e68c0c8b1ead56389f90c0d273", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-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" "-w" "/opt/rustwide/workdir" "--user" "0:0" "03808d6c213cf9ce707c2ba0c946506b9108a3e68c0c8b1ead56389f90c0d273" "/opt/rustwide/cargo-home/bin/cargo" "+21cad1f647cfd05a566220f933edd88a53e50bcf" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.50
[INFO] [stderr]     Checking rand_os v0.1.3
[INFO] [stderr]     Checking rand v0.6.5
[INFO] [stderr]     Checking hw4 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/problem1.rs:95:37
[INFO] [stdout]    |
[INFO] [stdout] 95 | pub fn filter(vs: &Vec<i32>, pred: &Fn(i32) -> bool) -> Vec<i32> {
[INFO] [stdout]    |                                     ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` (part of `#[warn(rust_2021_compatibility)]`) on by default
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 95 | pub fn filter(vs: &Vec<i32>, pred: &dyn Fn(i32) -> bool) -> Vec<i32> {
[INFO] [stdout]    |                                     +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/problem1.rs:95:37
[INFO] [stdout]    |
[INFO] [stdout] 95 | pub fn filter(vs: &Vec<i32>, pred: &Fn(i32) -> bool) -> Vec<i32> {
[INFO] [stdout]    |                                     ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` (part of `#[warn(rust_2021_compatibility)]`) on by default
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 95 | pub fn filter(vs: &Vec<i32>, pred: &dyn Fn(i32) -> bool) -> Vec<i32> {
[INFO] [stdout]    |                                     +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `eval` is never read
[INFO] [stdout]    --> src/problem1.rs:96:20
[INFO] [stdout]     |
[INFO] [stdout]  96 |     let mut eval = false;
[INFO] [stdout]     |                    ^^^^^ this value is reassigned later and never used
[INFO] [stdout] ...
[INFO] [stdout] 101 |         eval = pred(vs[i]);
[INFO] [stdout]     |         ------------------ `eval` is overwritten here before the previous value is read
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_assignments)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/problem2.rs:29:9
[INFO] [stdout]    |
[INFO] [stdout] 29 |     let mut test_vec = &mat1[0];
[INFO] [stdout]    |         ----^^^^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `p00`
[INFO] [stdout]   --> src/problem2.rs:30:9
[INFO] [stdout]    |
[INFO] [stdout] 30 |     let p00 = &mat1[0][0];
[INFO] [stdout]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_p00`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `temp_val`
[INFO] [stdout]   --> src/problem2.rs:64:21
[INFO] [stdout]    |
[INFO] [stdout] 64 |                 let temp_val = &mat1[i][k] * &mat2[k][j];
[INFO] [stdout]    |                     ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_temp_val`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `j` is never read
[INFO] [stdout]   --> src/problem2.rs:35:17
[INFO] [stdout]    |
[INFO] [stdout] 35 |     let mut j = 0;
[INFO] [stdout]    |                 ^ this value is reassigned later and never used
[INFO] [stdout] ...
[INFO] [stdout] 54 |     j = 0;
[INFO] [stdout]    |     ----- `j` is overwritten here before the previous value is read
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `j` is never read
[INFO] [stdout]   --> src/problem2.rs:54:5
[INFO] [stdout]    |
[INFO] [stdout] 54 |     j = 0;
[INFO] [stdout]    |     ^^^^^ this value is reassigned later and never used
[INFO] [stdout] ...
[INFO] [stdout] 58 |         j = 0;
[INFO] [stdout]    |         ----- `j` is overwritten here before the previous value is read
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `k` is never read
[INFO] [stdout]   --> src/problem2.rs:36:17
[INFO] [stdout]    |
[INFO] [stdout] 36 |     let mut k = 0;
[INFO] [stdout]    |                 ^ this value is reassigned later and never used
[INFO] [stdout] ...
[INFO] [stdout] 55 |     k = 0;
[INFO] [stdout]    |     ----- `k` is overwritten here before the previous value is read
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `k` is never read
[INFO] [stdout]   --> src/problem2.rs:55:5
[INFO] [stdout]    |
[INFO] [stdout] 55 |     k = 0;
[INFO] [stdout]    |     ^^^^^ this value is reassigned later and never used
[INFO] [stdout] ...
[INFO] [stdout] 61 |             k = 0;
[INFO] [stdout]    |             ----- `k` is overwritten here before the previous value is read
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/problem4.rs:133:9
[INFO] [stdout]     |
[INFO] [stdout] 133 |     let mut empty_vals = vec![num_discs];
[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/problem4.rs:135:9
[INFO] [stdout]     |
[INFO] [stdout] 135 |     let mut aux_disks = Vec::new();
[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/problem4.rs:136:9
[INFO] [stdout]     |
[INFO] [stdout] 136 |     let mut dst_disks = Vec::new();
[INFO] [stdout]     |         ----^^^^^^^^^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]    --> src/problem4.rs:139:9
[INFO] [stdout]     |
[INFO] [stdout] 139 |     for x in 0..num_discs{
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `counter` is never read
[INFO] [stdout]    --> src/problem4.rs:309:9
[INFO] [stdout]     |
[INFO] [stdout] 309 |         counter = 0;
[INFO] [stdout]     |         ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `counter` is never read
[INFO] [stdout]    --> src/problem4.rs:226:9
[INFO] [stdout]     |
[INFO] [stdout] 226 |         counter = 0;
[INFO] [stdout]     |         ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/rpn.rs:286:21
[INFO] [stdout]     |
[INFO] [stdout] 286 |                 let mut tf = false;
[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/rpn.rs:423:21
[INFO] [stdout]     |
[INFO] [stdout] 423 |                 let mut first = self.pop()?;
[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/rpn.rs:424:21
[INFO] [stdout]     |
[INFO] [stdout] 424 |                 let mut second = self.pop()?;
[INFO] [stdout]     |                     ----^^^^^^
[INFO] [stdout]     |                     |
[INFO] [stdout]     |                     help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `value`
[INFO] [stdout]    --> src/rpn.rs:179:32
[INFO] [stdout]     |
[INFO] [stdout] 179 |                     Item::Bool(value)  => {
[INFO] [stdout]     |                                ^^^^^ help: if this is intentional, prefix it with an underscore: `_value`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `inside`
[INFO] [stdout]    --> src/rpn.rs:190:42
[INFO] [stdout]     |
[INFO] [stdout] 190 |                 } else if let Item::Bool(inside) = second {
[INFO] [stdout]     |                                          ^^^^^^ help: if this is intentional, prefix it with an underscore: `_inside`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `value`
[INFO] [stdout]    --> src/rpn.rs:245:32
[INFO] [stdout]     |
[INFO] [stdout] 245 |                     Item::Bool(value)  => {
[INFO] [stdout]     |                                ^^^^^ help: if this is intentional, prefix it with an underscore: `_value`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `value`
[INFO] [stdout]    --> src/rpn.rs:256:32
[INFO] [stdout]     |
[INFO] [stdout] 256 |                     Item::Bool(value)  => {
[INFO] [stdout]     |                                ^^^^^ help: if this is intentional, prefix it with an underscore: `_value`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `value`
[INFO] [stdout]    --> src/rpn.rs:355:31
[INFO] [stdout]     |
[INFO] [stdout] 355 |                     Item::Int(value) => {
[INFO] [stdout]     |                               ^^^^^ help: if this is intentional, prefix it with an underscore: `_value`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `value`
[INFO] [stdout]    --> src/rpn.rs:399:32
[INFO] [stdout]     |
[INFO] [stdout] 399 |                     Item::Bool(value)  => {
[INFO] [stdout]     |                                ^^^^^ help: if this is intentional, prefix it with an underscore: `_value`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `eval` is never read
[INFO] [stdout]    --> src/problem1.rs:96:20
[INFO] [stdout]     |
[INFO] [stdout]  96 |     let mut eval = false;
[INFO] [stdout]     |                    ^^^^^ this value is reassigned later and never used
[INFO] [stdout] ...
[INFO] [stdout] 101 |         eval = pred(vs[i]);
[INFO] [stdout]     |         ------------------ `eval` is overwritten here before the previous value is read
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_assignments)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: comparison is useless due to type limits
[INFO] [stdout]   --> src/problem3.rs:17:8
[INFO] [stdout]    |
[INFO] [stdout] 17 |     if n < 0 {
[INFO] [stdout]    |        ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_comparisons)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `canSwap` should have a snake case name
[INFO] [stdout]   --> src/problem4.rs:36:4
[INFO] [stdout]    |
[INFO] [stdout] 36 | fn canSwap (start: &Vec<u32>, end: &Vec<u32>) -> bool{
[INFO] [stdout]    |    ^^^^^^^ help: convert the identifier to snake case: `can_swap`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_snake_case)]` (part of `#[warn(nonstandard_style)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `findNext` should have a snake case name
[INFO] [stdout]   --> src/problem4.rs:77:4
[INFO] [stdout]    |
[INFO] [stdout] 77 | fn findNext (src: u32, disks: &Vec<Vec<u32>>) -> usize{
[INFO] [stdout]    |    ^^^^^^^^ help: convert the identifier to snake case: `find_next`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `nextP` should have a snake case name
[INFO] [stdout]    --> src/problem4.rs:149:9
[INFO] [stdout]     |
[INFO] [stdout] 149 |     let nextP = findNext(1, &disks);
[INFO] [stdout]     |         ^^^^^ help: convert the identifier to snake case: `next_p`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/problem2.rs:29:9
[INFO] [stdout]    |
[INFO] [stdout] 29 |     let mut test_vec = &mat1[0];
[INFO] [stdout]    |         ----^^^^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `p00`
[INFO] [stdout]   --> src/problem2.rs:30:9
[INFO] [stdout]    |
[INFO] [stdout] 30 |     let p00 = &mat1[0][0];
[INFO] [stdout]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_p00`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `temp_val`
[INFO] [stdout]   --> src/problem2.rs:64:21
[INFO] [stdout]    |
[INFO] [stdout] 64 |                 let temp_val = &mat1[i][k] * &mat2[k][j];
[INFO] [stdout]    |                     ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_temp_val`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `j` is never read
[INFO] [stdout]   --> src/problem2.rs:35:17
[INFO] [stdout]    |
[INFO] [stdout] 35 |     let mut j = 0;
[INFO] [stdout]    |                 ^ this value is reassigned later and never used
[INFO] [stdout] ...
[INFO] [stdout] 54 |     j = 0;
[INFO] [stdout]    |     ----- `j` is overwritten here before the previous value is read
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `j` is never read
[INFO] [stdout]   --> src/problem2.rs:54:5
[INFO] [stdout]    |
[INFO] [stdout] 54 |     j = 0;
[INFO] [stdout]    |     ^^^^^ this value is reassigned later and never used
[INFO] [stdout] ...
[INFO] [stdout] 58 |         j = 0;
[INFO] [stdout]    |         ----- `j` is overwritten here before the previous value is read
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `k` is never read
[INFO] [stdout]   --> src/problem2.rs:36:17
[INFO] [stdout]    |
[INFO] [stdout] 36 |     let mut k = 0;
[INFO] [stdout]    |                 ^ this value is reassigned later and never used
[INFO] [stdout] ...
[INFO] [stdout] 55 |     k = 0;
[INFO] [stdout]    |     ----- `k` is overwritten here before the previous value is read
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `k` is never read
[INFO] [stdout]   --> src/problem2.rs:55:5
[INFO] [stdout]    |
[INFO] [stdout] 55 |     k = 0;
[INFO] [stdout]    |     ^^^^^ this value is reassigned later and never used
[INFO] [stdout] ...
[INFO] [stdout] 61 |             k = 0;
[INFO] [stdout]    |             ----- `k` is overwritten here before the previous value is read
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/parser.rs:64:21
[INFO] [stdout]    |
[INFO] [stdout] 64 |                     stack.push(rpn::Item::Int(i));
[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] 64 |                     let _ = stack.push(rpn::Item::Int(i));
[INFO] [stdout]    |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/parser.rs:76:21
[INFO] [stdout]    |
[INFO] [stdout] 76 |                     stack.push(rpn::Item::Bool(i));
[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] 76 |                     let _ = stack.push(rpn::Item::Bool(i));
[INFO] [stdout]    |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/parser.rs:87:17
[INFO] [stdout]    |
[INFO] [stdout] 87 |                 stack.eval(rpn::Op::Add);
[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] 87 |                 let _ = stack.eval(rpn::Op::Add);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/parser.rs:90:17
[INFO] [stdout]    |
[INFO] [stdout] 90 |                 stack.eval(rpn::Op::Eq);
[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] 90 |                 let _ = stack.eval(rpn::Op::Eq);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/parser.rs:93:17
[INFO] [stdout]    |
[INFO] [stdout] 93 |                 stack.eval(rpn::Op::Neg);
[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] 93 |                 let _ = stack.eval(rpn::Op::Neg);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/parser.rs:96:17
[INFO] [stdout]    |
[INFO] [stdout] 96 |                 stack.eval(rpn::Op::Swap);
[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] 96 |                 let _ = stack.eval(rpn::Op::Swap);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/parser.rs:99:17
[INFO] [stdout]    |
[INFO] [stdout] 99 |                 stack.eval(rpn::Op::Rand);
[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] 99 |                 let _ = stack.eval(rpn::Op::Rand);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/parser.rs:102:17
[INFO] [stdout]     |
[INFO] [stdout] 102 |                 stack.eval(rpn::Op::Cond);
[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] 102 |                 let _ = stack.eval(rpn::Op::Cond);
[INFO] [stdout]     |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/parser.rs:105:17
[INFO] [stdout]     |
[INFO] [stdout] 105 |                 stack.eval(rpn::Op::Quit);
[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] 105 |                 let _ = stack.eval(rpn::Op::Quit);
[INFO] [stdout]     |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:198:21
[INFO] [stdout]     |
[INFO] [stdout] 198 |                     self.push(second);
[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] 198 |                     let _ = self.push(second);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:199:21
[INFO] [stdout]     |
[INFO] [stdout] 199 |                     self.push(first);
[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] 199 |                     let _ = self.push(first);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:204:17
[INFO] [stdout]     |
[INFO] [stdout] 204 |                 self.push(to_add);
[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] 204 |                 let _ = self.push(to_add);
[INFO] [stdout]     |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:264:21
[INFO] [stdout]     |
[INFO] [stdout] 264 |                     self.push(third);
[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] 264 |                     let _ = self.push(third);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:265:21
[INFO] [stdout]     |
[INFO] [stdout] 265 |                     self.push(second);
[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] 265 |                     let _ = self.push(second);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:266:21
[INFO] [stdout]     |
[INFO] [stdout] 266 |                     self.push(first);
[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] 266 |                     let _ = self.push(first);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:272:21
[INFO] [stdout]     |
[INFO] [stdout] 272 |                     self.push(to_add);
[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] 272 |                     let _ = self.push(to_add);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:276:21
[INFO] [stdout]     |
[INFO] [stdout] 276 |                     self.push(to_add);
[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] 276 |                     let _ = self.push(to_add);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:323:21
[INFO] [stdout]     |
[INFO] [stdout] 323 |                     self.push(second);
[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] 323 |                     let _ = self.push(second);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/problem4.rs:133:9
[INFO] [stdout]     |
[INFO] [stdout] 133 |     let mut empty_vals = vec![num_discs];
[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/problem4.rs:135:9
[INFO] [stdout]     |
[INFO] [stdout] 135 |     let mut aux_disks = Vec::new();
[INFO] [stdout]     |         ----^^^^^^^^^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:324:21
[INFO] [stdout]     |
[INFO] [stdout] 324 |                     self.push(first);
[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] 324 |                     let _ = self.push(first);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/problem4.rs:136:9
[INFO] [stdout]     |
[INFO] [stdout] 136 |     let mut dst_disks = Vec::new();
[INFO] [stdout]     |         ----^^^^^^^^^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:329:25
[INFO] [stdout]     |
[INFO] [stdout] 329 |                         self.push(to_add);
[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] 329 |                         let _ = self.push(to_add);
[INFO] [stdout]     |                         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:332:25
[INFO] [stdout]     |
[INFO] [stdout] 332 |                         self.push(to_add);
[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] 332 |                         let _ = self.push(to_add);
[INFO] [stdout]     |                         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:337:25
[INFO] [stdout]     |
[INFO] [stdout] 337 |                         self.push(to_add);
[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] 337 |                         let _ = self.push(to_add);
[INFO] [stdout]     |                         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:340:25
[INFO] [stdout]     |
[INFO] [stdout] 340 |                         self.push(to_add);
[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] 340 |                         let _ = self.push(to_add);
[INFO] [stdout]     |                         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]    --> src/problem4.rs:139:9
[INFO] [stdout]     |
[INFO] [stdout] 139 |     for x in 0..num_discs{
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:366:21
[INFO] [stdout]     |
[INFO] [stdout] 366 |                     self.push(first);
[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] 366 |                     let _ = self.push(first);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:372:21
[INFO] [stdout]     |
[INFO] [stdout] 372 |                     self.push(to_add);
[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] 372 |                     let _ = self.push(to_add);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:376:21
[INFO] [stdout]     |
[INFO] [stdout] 376 |                     self.push(to_add);
[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] 376 |                     let _ = self.push(to_add);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:406:21
[INFO] [stdout]     |
[INFO] [stdout] 406 |                     self.push(first);
[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] 406 |                     let _ = self.push(first);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:414:17
[INFO] [stdout]     |
[INFO] [stdout] 414 |                 self.push(to_add);
[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] 414 |                 let _ = self.push(to_add);
[INFO] [stdout]     |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `counter` is never read
[INFO] [stdout]    --> src/problem4.rs:309:9
[INFO] [stdout]     |
[INFO] [stdout] 309 |         counter = 0;
[INFO] [stdout]     |         ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `counter` is never read
[INFO] [stdout]    --> src/problem4.rs:226:9
[INFO] [stdout]     |
[INFO] [stdout] 226 |         counter = 0;
[INFO] [stdout]     |         ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:425:17
[INFO] [stdout]     |
[INFO] [stdout] 425 |                 self.push(first);
[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] 425 |                 let _ = self.push(first);
[INFO] [stdout]     |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:426:17
[INFO] [stdout]     |
[INFO] [stdout] 426 |                 self.push(second);
[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] 426 |                 let _ = self.push(second);
[INFO] [stdout]     |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/rpn.rs:286:21
[INFO] [stdout]     |
[INFO] [stdout] 286 |                 let mut tf = false;
[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/rpn.rs:423:21
[INFO] [stdout]     |
[INFO] [stdout] 423 |                 let mut first = self.pop()?;
[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/rpn.rs:424:21
[INFO] [stdout]     |
[INFO] [stdout] 424 |                 let mut second = self.pop()?;
[INFO] [stdout]     |                     ----^^^^^^
[INFO] [stdout]     |                     |
[INFO] [stdout]     |                     help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `value`
[INFO] [stdout]    --> src/rpn.rs:179:32
[INFO] [stdout]     |
[INFO] [stdout] 179 |                     Item::Bool(value)  => {
[INFO] [stdout]     |                                ^^^^^ help: if this is intentional, prefix it with an underscore: `_value`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `inside`
[INFO] [stdout]    --> src/rpn.rs:190:42
[INFO] [stdout]     |
[INFO] [stdout] 190 |                 } else if let Item::Bool(inside) = second {
[INFO] [stdout]     |                                          ^^^^^^ help: if this is intentional, prefix it with an underscore: `_inside`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `value`
[INFO] [stdout]    --> src/rpn.rs:245:32
[INFO] [stdout]     |
[INFO] [stdout] 245 |                     Item::Bool(value)  => {
[INFO] [stdout]     |                                ^^^^^ help: if this is intentional, prefix it with an underscore: `_value`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `value`
[INFO] [stdout]    --> src/rpn.rs:256:32
[INFO] [stdout]     |
[INFO] [stdout] 256 |                     Item::Bool(value)  => {
[INFO] [stdout]     |                                ^^^^^ help: if this is intentional, prefix it with an underscore: `_value`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `value`
[INFO] [stdout]    --> src/rpn.rs:355:31
[INFO] [stdout]     |
[INFO] [stdout] 355 |                     Item::Int(value) => {
[INFO] [stdout]     |                               ^^^^^ help: if this is intentional, prefix it with an underscore: `_value`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `value`
[INFO] [stdout]    --> src/rpn.rs:399:32
[INFO] [stdout]     |
[INFO] [stdout] 399 |                     Item::Bool(value)  => {
[INFO] [stdout]     |                                ^^^^^ help: if this is intentional, prefix it with an underscore: `_value`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: comparison is useless due to type limits
[INFO] [stdout]   --> src/problem3.rs:17:8
[INFO] [stdout]    |
[INFO] [stdout] 17 |     if n < 0 {
[INFO] [stdout]    |        ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_comparisons)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `canSwap` should have a snake case name
[INFO] [stdout]   --> src/problem4.rs:36:4
[INFO] [stdout]    |
[INFO] [stdout] 36 | fn canSwap (start: &Vec<u32>, end: &Vec<u32>) -> bool{
[INFO] [stdout]    |    ^^^^^^^ help: convert the identifier to snake case: `can_swap`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_snake_case)]` (part of `#[warn(nonstandard_style)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `findNext` should have a snake case name
[INFO] [stdout]   --> src/problem4.rs:77:4
[INFO] [stdout]    |
[INFO] [stdout] 77 | fn findNext (src: u32, disks: &Vec<Vec<u32>>) -> usize{
[INFO] [stdout]    |    ^^^^^^^^ help: convert the identifier to snake case: `find_next`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `nextP` should have a snake case name
[INFO] [stdout]    --> src/problem4.rs:149:9
[INFO] [stdout]     |
[INFO] [stdout] 149 |     let nextP = findNext(1, &disks);
[INFO] [stdout]     |         ^^^^^ help: convert the identifier to snake case: `next_p`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/parser.rs:64:21
[INFO] [stdout]    |
[INFO] [stdout] 64 |                     stack.push(rpn::Item::Int(i));
[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] 64 |                     let _ = stack.push(rpn::Item::Int(i));
[INFO] [stdout]    |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/parser.rs:76:21
[INFO] [stdout]    |
[INFO] [stdout] 76 |                     stack.push(rpn::Item::Bool(i));
[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] 76 |                     let _ = stack.push(rpn::Item::Bool(i));
[INFO] [stdout]    |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/parser.rs:87:17
[INFO] [stdout]    |
[INFO] [stdout] 87 |                 stack.eval(rpn::Op::Add);
[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] 87 |                 let _ = stack.eval(rpn::Op::Add);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/parser.rs:90:17
[INFO] [stdout]    |
[INFO] [stdout] 90 |                 stack.eval(rpn::Op::Eq);
[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] 90 |                 let _ = stack.eval(rpn::Op::Eq);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/parser.rs:93:17
[INFO] [stdout]    |
[INFO] [stdout] 93 |                 stack.eval(rpn::Op::Neg);
[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] 93 |                 let _ = stack.eval(rpn::Op::Neg);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/parser.rs:96:17
[INFO] [stdout]    |
[INFO] [stdout] 96 |                 stack.eval(rpn::Op::Swap);
[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] 96 |                 let _ = stack.eval(rpn::Op::Swap);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/parser.rs:99:17
[INFO] [stdout]    |
[INFO] [stdout] 99 |                 stack.eval(rpn::Op::Rand);
[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] 99 |                 let _ = stack.eval(rpn::Op::Rand);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/parser.rs:102:17
[INFO] [stdout]     |
[INFO] [stdout] 102 |                 stack.eval(rpn::Op::Cond);
[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] 102 |                 let _ = stack.eval(rpn::Op::Cond);
[INFO] [stdout]     |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/parser.rs:105:17
[INFO] [stdout]     |
[INFO] [stdout] 105 |                 stack.eval(rpn::Op::Quit);
[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] 105 |                 let _ = stack.eval(rpn::Op::Quit);
[INFO] [stdout]     |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:198:21
[INFO] [stdout]     |
[INFO] [stdout] 198 |                     self.push(second);
[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] 198 |                     let _ = self.push(second);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:199:21
[INFO] [stdout]     |
[INFO] [stdout] 199 |                     self.push(first);
[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] 199 |                     let _ = self.push(first);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:204:17
[INFO] [stdout]     |
[INFO] [stdout] 204 |                 self.push(to_add);
[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] 204 |                 let _ = self.push(to_add);
[INFO] [stdout]     |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:264:21
[INFO] [stdout]     |
[INFO] [stdout] 264 |                     self.push(third);
[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] 264 |                     let _ = self.push(third);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:265:21
[INFO] [stdout]     |
[INFO] [stdout] 265 |                     self.push(second);
[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] 265 |                     let _ = self.push(second);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:266:21
[INFO] [stdout]     |
[INFO] [stdout] 266 |                     self.push(first);
[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] 266 |                     let _ = self.push(first);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:272:21
[INFO] [stdout]     |
[INFO] [stdout] 272 |                     self.push(to_add);
[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] 272 |                     let _ = self.push(to_add);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:276:21
[INFO] [stdout]     |
[INFO] [stdout] 276 |                     self.push(to_add);
[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] 276 |                     let _ = self.push(to_add);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:323:21
[INFO] [stdout]     |
[INFO] [stdout] 323 |                     self.push(second);
[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] 323 |                     let _ = self.push(second);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:324:21
[INFO] [stdout]     |
[INFO] [stdout] 324 |                     self.push(first);
[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] 324 |                     let _ = self.push(first);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:329:25
[INFO] [stdout]     |
[INFO] [stdout] 329 |                         self.push(to_add);
[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] 329 |                         let _ = self.push(to_add);
[INFO] [stdout]     |                         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:332:25
[INFO] [stdout]     |
[INFO] [stdout] 332 |                         self.push(to_add);
[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] 332 |                         let _ = self.push(to_add);
[INFO] [stdout]     |                         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:337:25
[INFO] [stdout]     |
[INFO] [stdout] 337 |                         self.push(to_add);
[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] 337 |                         let _ = self.push(to_add);
[INFO] [stdout]     |                         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:340:25
[INFO] [stdout]     |
[INFO] [stdout] 340 |                         self.push(to_add);
[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] 340 |                         let _ = self.push(to_add);
[INFO] [stdout]     |                         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:366:21
[INFO] [stdout]     |
[INFO] [stdout] 366 |                     self.push(first);
[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] 366 |                     let _ = self.push(first);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:372:21
[INFO] [stdout]     |
[INFO] [stdout] 372 |                     self.push(to_add);
[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] 372 |                     let _ = self.push(to_add);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:376:21
[INFO] [stdout]     |
[INFO] [stdout] 376 |                     self.push(to_add);
[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] 376 |                     let _ = self.push(to_add);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:406:21
[INFO] [stdout]     |
[INFO] [stdout] 406 |                     self.push(first);
[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] 406 |                     let _ = self.push(first);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:414:17
[INFO] [stdout]     |
[INFO] [stdout] 414 |                 self.push(to_add);
[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] 414 |                 let _ = self.push(to_add);
[INFO] [stdout]     |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:425:17
[INFO] [stdout]     |
[INFO] [stdout] 425 |                 self.push(first);
[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] 425 |                 let _ = self.push(first);
[INFO] [stdout]     |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/rpn.rs:426:17
[INFO] [stdout]     |
[INFO] [stdout] 426 |                 self.push(second);
[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] 426 |                 let _ = self.push(second);
[INFO] [stdout]     |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 2.26s
[INFO] running `Command { std: "docker" "inspect" "03808d6c213cf9ce707c2ba0c946506b9108a3e68c0c8b1ead56389f90c0d273", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "03808d6c213cf9ce707c2ba0c946506b9108a3e68c0c8b1ead56389f90c0d273", kill_on_drop: false }`
[INFO] [stdout] 03808d6c213cf9ce707c2ba0c946506b9108a3e68c0c8b1ead56389f90c0d273
