[INFO] cloning repository https://github.com/iasoon/het
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/iasoon/het" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fiasoon%2Fhet", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fiasoon%2Fhet'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 7d2ff0ac751b08f089605216e26ba5acfac291ae
[INFO] testing iasoon/het against beta-2021-09-08 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fiasoon%2Fhet" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/iasoon/het on toolchain beta-2021-09-08
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/iasoon/het
[INFO] finished tweaking git repo https://github.com/iasoon/het
[INFO] tweaked toml for git repo https://github.com/iasoon/het written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/iasoon/het already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] c0176c4cdc2208c4d7b61b850c29b7cebb9819694624b3f1e3b8344d37312013
[INFO] running `Command { std: "docker" "start" "-a" "c0176c4cdc2208c4d7b61b850c29b7cebb9819694624b3f1e3b8344d37312013", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c0176c4cdc2208c4d7b61b850c29b7cebb9819694624b3f1e3b8344d37312013", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c0176c4cdc2208c4d7b61b850c29b7cebb9819694624b3f1e3b8344d37312013", kill_on_drop: false }`
[INFO] [stdout] c0176c4cdc2208c4d7b61b850c29b7cebb9819694624b3f1e3b8344d37312013
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d8b531e3d4ece0872d1af8ae8f75b4a608114096ba3b65e84345ea02417858d9
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "d8b531e3d4ece0872d1af8ae8f75b4a608114096ba3b65e84345ea02417858d9", kill_on_drop: false }`
[INFO] [stderr]    Compiling de-het-taal v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::collections::HashMap`
[INFO] [stdout]  --> src/types.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::collections::HashMap;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `arg_type`
[INFO] [stdout]    --> src/types.rs:129:21
[INFO] [stdout]     |
[INFO] [stdout] 129 |                 let arg_type = match &arg.type_name {
[INFO] [stdout]     |                     ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_arg_type`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/lexer.rs:72:33
[INFO] [stdout]    |
[INFO] [stdout] 72 |     fn read_while<P>(&mut self, mut pred: P) -> String
[INFO] [stdout]    |                                 ----^^^^
[INFO] [stdout]    |                                 |
[INFO] [stdout]    |                                 help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `pos`
[INFO] [stdout]   --> src/lexer.rs:54:8
[INFO] [stdout]    |
[INFO] [stdout] 54 |     fn pos(&self) -> Option<char> {
[INFO] [stdout]    |        ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `read_while`
[INFO] [stdout]   --> src/lexer.rs:72:8
[INFO] [stdout]    |
[INFO] [stdout] 72 |     fn read_while<P>(&mut self, mut pred: P) -> String
[INFO] [stdout]    |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `PrimitiveFn`
[INFO] [stdout]  --> src/evaluator.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 8 |     PrimitiveFn(&'static dyn Fn(&[Value]) -> Result<Value, String>),
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Number`
[INFO] [stdout]  --> src/evaluator.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 |     Number(f64),
[INFO] [stdout]   |     ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Lambda`
[INFO] [stdout]   --> src/evaluator.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 10 |     Lambda { args: Vec<String>, body: Closure },
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `resolve`
[INFO] [stdout]   --> src/evaluator.rs:37:8
[INFO] [stdout]    |
[INFO] [stdout] 37 |     fn resolve<'a>(&'a self, name: &str) -> Option<&'a Value> {
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `default`
[INFO] [stdout]   --> src/evaluator.rs:41:8
[INFO] [stdout]    |
[INFO] [stdout] 41 |     fn default() -> Env {
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `eval`
[INFO] [stdout]   --> src/evaluator.rs:48:8
[INFO] [stdout]    |
[INFO] [stdout] 48 | pub fn eval(expr: &Expr) -> Result<Value, String> {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `eval_`
[INFO] [stdout]   --> src/evaluator.rs:53:4
[INFO] [stdout]    |
[INFO] [stdout] 53 | fn eval_(env: &Env, expr: &Expr) -> Result<Value, String> {
[INFO] [stdout]    |    ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `apply`
[INFO] [stdout]   --> src/evaluator.rs:80:4
[INFO] [stdout]    |
[INFO] [stdout] 80 | fn apply(abs: &Value, args: &[Value]) -> Result<Value, String> {
[INFO] [stdout]    |    ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `fun_add`
[INFO] [stdout]   --> src/evaluator.rs:96:4
[INFO] [stdout]    |
[INFO] [stdout] 96 | fn fun_add(values: &[Value]) -> Result<Value, String> {
[INFO] [stdout]    |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Eq`
[INFO] [stdout]   --> src/types.rs:35:5
[INFO] [stdout]    |
[INFO] [stdout] 35 |     Eq { t1: Type, t2: Type }
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 15 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.36s
[INFO] running `Command { std: "docker" "inspect" "d8b531e3d4ece0872d1af8ae8f75b4a608114096ba3b65e84345ea02417858d9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d8b531e3d4ece0872d1af8ae8f75b4a608114096ba3b65e84345ea02417858d9", kill_on_drop: false }`
[INFO] [stdout] d8b531e3d4ece0872d1af8ae8f75b4a608114096ba3b65e84345ea02417858d9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] eb7e312fe1e6774f1394bf38b92826ec9ddf9250bedaad5d73635f69c38660ff
[INFO] running `Command { std: "docker" "start" "-a" "eb7e312fe1e6774f1394bf38b92826ec9ddf9250bedaad5d73635f69c38660ff", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling de-het-taal v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::collections::HashMap`
[INFO] [stdout]  --> src/types.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::collections::HashMap;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `arg_type`
[INFO] [stdout]    --> src/types.rs:129:21
[INFO] [stdout]     |
[INFO] [stdout] 129 |                 let arg_type = match &arg.type_name {
[INFO] [stdout]     |                     ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_arg_type`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/lexer.rs:72:33
[INFO] [stdout]    |
[INFO] [stdout] 72 |     fn read_while<P>(&mut self, mut pred: P) -> String
[INFO] [stdout]    |                                 ----^^^^
[INFO] [stdout]    |                                 |
[INFO] [stdout]    |                                 help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `pos`
[INFO] [stdout]   --> src/lexer.rs:54:8
[INFO] [stdout]    |
[INFO] [stdout] 54 |     fn pos(&self) -> Option<char> {
[INFO] [stdout]    |        ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `read_while`
[INFO] [stdout]   --> src/lexer.rs:72:8
[INFO] [stdout]    |
[INFO] [stdout] 72 |     fn read_while<P>(&mut self, mut pred: P) -> String
[INFO] [stdout]    |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `PrimitiveFn`
[INFO] [stdout]  --> src/evaluator.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 8 |     PrimitiveFn(&'static dyn Fn(&[Value]) -> Result<Value, String>),
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Number`
[INFO] [stdout]  --> src/evaluator.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 |     Number(f64),
[INFO] [stdout]   |     ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Lambda`
[INFO] [stdout]   --> src/evaluator.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 10 |     Lambda { args: Vec<String>, body: Closure },
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `resolve`
[INFO] [stdout]   --> src/evaluator.rs:37:8
[INFO] [stdout]    |
[INFO] [stdout] 37 |     fn resolve<'a>(&'a self, name: &str) -> Option<&'a Value> {
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `default`
[INFO] [stdout]   --> src/evaluator.rs:41:8
[INFO] [stdout]    |
[INFO] [stdout] 41 |     fn default() -> Env {
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `eval`
[INFO] [stdout]   --> src/evaluator.rs:48:8
[INFO] [stdout]    |
[INFO] [stdout] 48 | pub fn eval(expr: &Expr) -> Result<Value, String> {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `eval_`
[INFO] [stdout]   --> src/evaluator.rs:53:4
[INFO] [stdout]    |
[INFO] [stdout] 53 | fn eval_(env: &Env, expr: &Expr) -> Result<Value, String> {
[INFO] [stdout]    |    ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `apply`
[INFO] [stdout]   --> src/evaluator.rs:80:4
[INFO] [stdout]    |
[INFO] [stdout] 80 | fn apply(abs: &Value, args: &[Value]) -> Result<Value, String> {
[INFO] [stdout]    |    ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `fun_add`
[INFO] [stdout]   --> src/evaluator.rs:96:4
[INFO] [stdout]    |
[INFO] [stdout] 96 | fn fun_add(values: &[Value]) -> Result<Value, String> {
[INFO] [stdout]    |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Eq`
[INFO] [stdout]   --> src/types.rs:35:5
[INFO] [stdout]    |
[INFO] [stdout] 35 |     Eq { t1: Type, t2: Type }
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 15 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.61s
[INFO] running `Command { std: "docker" "inspect" "eb7e312fe1e6774f1394bf38b92826ec9ddf9250bedaad5d73635f69c38660ff", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "eb7e312fe1e6774f1394bf38b92826ec9ddf9250bedaad5d73635f69c38660ff", kill_on_drop: false }`
[INFO] [stdout] eb7e312fe1e6774f1394bf38b92826ec9ddf9250bedaad5d73635f69c38660ff
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "test" "--frozen", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 5a5324b788d53a52daf3a3d1ceffce21b951ddc99a0258602437648e7ab28cba
[INFO] running `Command { std: "docker" "start" "-a" "5a5324b788d53a52daf3a3d1ceffce21b951ddc99a0258602437648e7ab28cba", kill_on_drop: false }`
[INFO] [stderr] warning: unused import: `std::collections::HashMap`
[INFO] [stderr]  --> src/types.rs:5:5
[INFO] [stderr]   |
[INFO] [stderr] 5 | use std::collections::HashMap;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `arg_type`
[INFO] [stderr]    --> src/types.rs:129:21
[INFO] [stderr]     |
[INFO] [stderr] 129 |                 let arg_type = match &arg.type_name {
[INFO] [stderr]     |                     ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_arg_type`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/lexer.rs:72:33
[INFO] [stderr]    |
[INFO] [stderr] 72 |     fn read_while<P>(&mut self, mut pred: P) -> String
[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: associated function is never used: `pos`
[INFO] [stderr]   --> src/lexer.rs:54:8
[INFO] [stderr]    |
[INFO] [stderr] 54 |     fn pos(&self) -> Option<char> {
[INFO] [stderr]    |        ^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `read_while`
[INFO] [stderr]   --> src/lexer.rs:72:8
[INFO] [stderr]    |
[INFO] [stderr] 72 |     fn read_while<P>(&mut self, mut pred: P) -> String
[INFO] [stderr]    |        ^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: variant is never constructed: `PrimitiveFn`
[INFO] [stderr]  --> src/evaluator.rs:8:5
[INFO] [stderr]   |
[INFO] [stderr] 8 |     PrimitiveFn(&'static dyn Fn(&[Value]) -> Result<Value, String>),
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: variant is never constructed: `Number`
[INFO] [stderr]  --> src/evaluator.rs:9:5
[INFO] [stderr]   |
[INFO] [stderr] 9 |     Number(f64),
[INFO] [stderr]   |     ^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: variant is never constructed: `Lambda`
[INFO] [stderr]   --> src/evaluator.rs:10:5
[INFO] [stderr]    |
[INFO] [stderr] 10 |     Lambda { args: Vec<String>, body: Closure },
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `resolve`
[INFO] [stderr]   --> src/evaluator.rs:37:8
[INFO] [stderr]    |
[INFO] [stderr] 37 |     fn resolve<'a>(&'a self, name: &str) -> Option<&'a Value> {
[INFO] [stderr]    |        ^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `default`
[INFO] [stderr]   --> src/evaluator.rs:41:8
[INFO] [stderr]    |
[INFO] [stderr] 41 |     fn default() -> Env {
[INFO] [stderr]    |        ^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `eval`
[INFO] [stderr]   --> src/evaluator.rs:48:8
[INFO] [stderr]    |
[INFO] [stderr] 48 | pub fn eval(expr: &Expr) -> Result<Value, String> {
[INFO] [stderr]    |        ^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `eval_`
[INFO] [stderr]   --> src/evaluator.rs:53:4
[INFO] [stderr]    |
[INFO] [stderr] 53 | fn eval_(env: &Env, expr: &Expr) -> Result<Value, String> {
[INFO] [stderr]    |    ^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `apply`
[INFO] [stderr]   --> src/evaluator.rs:80:4
[INFO] [stderr]    |
[INFO] [stderr] 80 | fn apply(abs: &Value, args: &[Value]) -> Result<Value, String> {
[INFO] [stderr]    |    ^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `fun_add`
[INFO] [stderr]   --> src/evaluator.rs:96:4
[INFO] [stderr]    |
[INFO] [stderr] 96 | fn fun_add(values: &[Value]) -> Result<Value, String> {
[INFO] [stderr]    |    ^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: variant is never constructed: `Eq`
[INFO] [stderr]   --> src/types.rs:35:5
[INFO] [stderr]    |
[INFO] [stderr] 35 |     Eq { t1: Type, t2: Type }
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: `de-het-taal` (bin "de-het-taal" test) generated 15 warnings
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stdout] 
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/de_het_taal-963ad74b799eaf6e)
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "5a5324b788d53a52daf3a3d1ceffce21b951ddc99a0258602437648e7ab28cba", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5a5324b788d53a52daf3a3d1ceffce21b951ddc99a0258602437648e7ab28cba", kill_on_drop: false }`
[INFO] [stdout] 5a5324b788d53a52daf3a3d1ceffce21b951ddc99a0258602437648e7ab28cba