[INFO] updating cached repository Darksecond/lox
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/Darksecond/lox
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/Darksecond/lox" "work/ex/clippy-test-run/sources/stable/gh/Darksecond/lox"`
[INFO] [stderr] Cloning into 'work/ex/clippy-test-run/sources/stable/gh/Darksecond/lox'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/Darksecond/lox" "work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/Darksecond/lox"`
[INFO] [stderr] Cloning into 'work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/Darksecond/lox'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 52d1368284d9f0173956740ad1b673cab768eb51
[INFO] sha for GitHub repo Darksecond/lox: 52d1368284d9f0173956740ad1b673cab768eb51
[INFO] validating manifest of Darksecond/lox on toolchain stable
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of Darksecond/lox on toolchain stable+rustflags=-Dclippy::into_iter_on_array
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing Darksecond/lox
[INFO] finished frobbing Darksecond/lox
[INFO] frobbed toml for Darksecond/lox written to work/ex/clippy-test-run/sources/stable/gh/Darksecond/lox/Cargo.toml
[INFO] started frobbing Darksecond/lox
[INFO] finished frobbing Darksecond/lox
[INFO] frobbed toml for Darksecond/lox written to work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/Darksecond/lox/Cargo.toml
[INFO] crate Darksecond/lox has a lockfile. skipping
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] linting Darksecond/lox against stable+rustflags=-Dclippy::into_iter_on_array for clippy-test-run
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/clippy-test-run/worker-5/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/Darksecond/lox:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid -Dclippy::into_iter_on_array" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+stable" "clippy" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 4203ac6b8b582b00db3055ebbb80cface8268c4bf9971dce96a10d6db659a8f3
[INFO] running `"docker" "start" "-a" "4203ac6b8b582b00db3055ebbb80cface8268c4bf9971dce96a10d6db659a8f3"`
[INFO] [stderr]     Checking lang v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: you seem to be trying to use match for destructuring a single pattern. Consider using `if let`
[INFO] [stderr]   --> src/tokenizer.rs:48:9
[INFO] [stderr]    |
[INFO] [stderr] 48 | /         match it.next() {
[INFO] [stderr] 49 | |             None => return false,
[INFO] [stderr] 50 | |             _ => (),
[INFO] [stderr] 51 | |         }
[INFO] [stderr]    | |_________^ help: try this: `if let None = it.next() { return false }`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::single_match)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#single_match
[INFO] [stderr] 
[INFO] [stderr] warning: you seem to be trying to use match for destructuring a single pattern. Consider using `if let`
[INFO] [stderr]    --> src/tokenizer.rs:113:17
[INFO] [stderr]     |
[INFO] [stderr] 113 | /                 match self.it.next() {
[INFO] [stderr] 114 | |                     // Skip last "
[INFO] [stderr] 115 | |                     None => panic!("Unterminated string"),
[INFO] [stderr] 116 | |                     _ => (),
[INFO] [stderr] 117 | |                 }
[INFO] [stderr]     | |_________________^ help: try this: `if let None = self.it.next() { panic!("Unterminated string") }`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#single_match
[INFO] [stderr] 
[INFO] [stderr] warning: you should consider deriving a `Default` implementation for `bytecode::Chunk`
[INFO] [stderr]   --> src/bytecode.rs:37:5
[INFO] [stderr]    |
[INFO] [stderr] 37 | /     pub fn new() -> Chunk {
[INFO] [stderr] 38 | |         Chunk {
[INFO] [stderr] 39 | |             instructions: vec![],
[INFO] [stderr] 40 | |             constants: vec![],
[INFO] [stderr] 41 | |         }
[INFO] [stderr] 42 | |     }
[INFO] [stderr]    | |_____^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::new_without_default_derive)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#new_without_default_derive
[INFO] [stderr] help: try this
[INFO] [stderr]    |
[INFO] [stderr] 31 | #[derive(Default)]
[INFO] [stderr]    |
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]   --> src/stmt_parser.rs:24:5
[INFO] [stderr]    |
[INFO] [stderr] 24 | /     match peek(it)? {
[INFO] [stderr] 25 | |         &Token::Var => parse_var_declaration(it),
[INFO] [stderr] 26 | |         &Token::Fun => parse_function_declaration(it),
[INFO] [stderr] 27 | |         &Token::Class => parse_class_declaration(it),
[INFO] [stderr] 28 | |         _ => parse_statement(it),
[INFO] [stderr] 29 | |     }
[INFO] [stderr]    | |_____^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::match_ref_pats)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]    |
[INFO] [stderr] 24 |     match *(peek(it)?) {
[INFO] [stderr] 25 |         Token::Var => parse_var_declaration(it),
[INFO] [stderr] 26 |         Token::Fun => parse_function_declaration(it),
[INFO] [stderr] 27 |         Token::Class => parse_class_declaration(it),
[INFO] [stderr]    |
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]   --> src/stmt_parser.rs:36:5
[INFO] [stderr]    |
[INFO] [stderr] 36 | /     match peek(it)? {
[INFO] [stderr] 37 | |         &Token::Print => parse_print_statement(it),
[INFO] [stderr] 38 | |         &Token::If => parse_if_statement(it),
[INFO] [stderr] 39 | |         &Token::LeftBrace => parse_block_statement(it),
[INFO] [stderr] ...  |
[INFO] [stderr] 43 | |         _ => parse_expr_statement(it),
[INFO] [stderr] 44 | |     }
[INFO] [stderr]    | |_____^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]    |
[INFO] [stderr] 36 |     match *(peek(it)?) {
[INFO] [stderr] 37 |         Token::Print => parse_print_statement(it),
[INFO] [stderr] 38 |         Token::If => parse_if_statement(it),
[INFO] [stderr] 39 |         Token::LeftBrace => parse_block_statement(it),
[INFO] [stderr] 40 |         Token::While => parse_while_statement(it),
[INFO] [stderr] 41 |         Token::Return => parse_return_statement(it),
[INFO] [stderr]  ...
[INFO] [stderr] 
[INFO] [stderr] warning: `if _ { .. } else { .. }` is an expression
[INFO] [stderr]    --> src/stmt_parser.rs:117:5
[INFO] [stderr]     |
[INFO] [stderr] 117 | /     let mut initializer: Option<Expr> = None;
[INFO] [stderr] 118 | |
[INFO] [stderr] 119 | |     if optionally(it, &Token::Equal)? {
[INFO] [stderr] 120 | |         initializer = Some(parse_expr(it)?);
[INFO] [stderr] 121 | |     }
[INFO] [stderr]     | |_____^ help: it is more idiomatic to write: `let <mut> initializer = if optionally(it, &Token::Equal)? { Some(parse_expr(it)?) } else { None };`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::useless_let_if_seq)] on by default
[INFO] [stderr]     = note: you might not need `mut` at all
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#useless_let_if_seq
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]    --> src/stmt_parser.rs:141:23
[INFO] [stderr]     |
[INFO] [stderr] 141 |       let initializer = match peek(it)? {
[INFO] [stderr]     |  _______________________^
[INFO] [stderr] 142 | |         &Token::Var => Some(parse_var_declaration(it)?),
[INFO] [stderr] 143 | |         &Token::Semicolon => {
[INFO] [stderr] 144 | |             expect(it, &Token::Semicolon)?;
[INFO] [stderr] ...   |
[INFO] [stderr] 147 | |         _ => Some(parse_expr_statement(it)?),
[INFO] [stderr] 148 | |     };
[INFO] [stderr]     | |_____^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]     |
[INFO] [stderr] 141 |     let initializer = match *(peek(it)?) {
[INFO] [stderr] 142 |         Token::Var => Some(parse_var_declaration(it)?),
[INFO] [stderr] 143 |         Token::Semicolon => {
[INFO] [stderr]     |
[INFO] [stderr] 
[INFO] [stderr] warning: `if _ { .. } else { .. }` is an expression
[INFO] [stderr]    --> src/stmt_parser.rs:181:5
[INFO] [stderr]     |
[INFO] [stderr] 181 | /     let mut expr: Option<Expr> = None;
[INFO] [stderr] 182 | |     if peek(it)? != &Token::Semicolon {
[INFO] [stderr] 183 | |         expr = Some(parse_expr(it)?);
[INFO] [stderr] 184 | |     }
[INFO] [stderr]     | |_____^ help: it is more idiomatic to write: `let <mut> expr = if peek(it)? != &Token::Semicolon { Some(parse_expr(it)?) } else { None };`
[INFO] [stderr]     |
[INFO] [stderr]     = note: you might not need `mut` at all
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#useless_let_if_seq
[INFO] [stderr] 
[INFO] [stderr] warning: `if _ { .. } else { .. }` is an expression
[INFO] [stderr]    --> src/stmt_parser.rs:233:5
[INFO] [stderr]     |
[INFO] [stderr] 233 | /     let mut else_stmt: Option<Stmt> = None;
[INFO] [stderr] 234 | |
[INFO] [stderr] 235 | |     if optionally(it, &Token::Else)? {
[INFO] [stderr] 236 | |         else_stmt = Some(parse_statement(it)?);
[INFO] [stderr] 237 | |     }
[INFO] [stderr]     | |_____^ help: it is more idiomatic to write: `let <mut> else_stmt = if optionally(it, &Token::Else)? { Some(parse_statement(it)?) } else { None };`
[INFO] [stderr]     |
[INFO] [stderr]     = note: you might not need `mut` at all
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#useless_let_if_seq
[INFO] [stderr] 
[INFO] [stderr] warning: you seem to be trying to use match for destructuring a single pattern. Consider using `if let`
[INFO] [stderr]   --> src/tokenizer.rs:48:9
[INFO] [stderr]    |
[INFO] [stderr] 48 | /         match it.next() {
[INFO] [stderr] 49 | |             None => return false,
[INFO] [stderr] 50 | |             _ => (),
[INFO] [stderr] 51 | |         }
[INFO] [stderr]    | |_________^ help: try this: `if let None = it.next() { return false }`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::single_match)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#single_match
[INFO] [stderr] 
[INFO] [stderr] warning: you seem to be trying to use match for destructuring a single pattern. Consider using `if let`
[INFO] [stderr]    --> src/tokenizer.rs:113:17
[INFO] [stderr]     |
[INFO] [stderr] 113 | /                 match self.it.next() {
[INFO] [stderr] 114 | |                     // Skip last "
[INFO] [stderr] 115 | |                     None => panic!("Unterminated string"),
[INFO] [stderr] 116 | |                     _ => (),
[INFO] [stderr] 117 | |                 }
[INFO] [stderr]     | |_________________^ help: try this: `if let None = self.it.next() { panic!("Unterminated string") }`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#single_match
[INFO] [stderr] 
[INFO] [stderr] warning: you should consider deriving a `Default` implementation for `bytecode::Chunk`
[INFO] [stderr]   --> src/bytecode.rs:37:5
[INFO] [stderr]    |
[INFO] [stderr] 37 | /     pub fn new() -> Chunk {
[INFO] [stderr] 38 | |         Chunk {
[INFO] [stderr] 39 | |             instructions: vec![],
[INFO] [stderr] 40 | |             constants: vec![],
[INFO] [stderr] 41 | |         }
[INFO] [stderr] 42 | |     }
[INFO] [stderr]    | |_____^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::new_without_default_derive)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#new_without_default_derive
[INFO] [stderr] help: try this
[INFO] [stderr]    |
[INFO] [stderr] 31 | #[derive(Default)]
[INFO] [stderr]    |
[INFO] [stderr] 
[INFO] [stderr] warning: this .into_iter() call is equivalent to .iter() and will not move the slice
[INFO] [stderr]   --> src/compiler.rs:83:40
[INFO] [stderr]    |
[INFO] [stderr] 83 |         let mut it = tokens.as_slice().into_iter().peekable();
[INFO] [stderr]    |                                        ^^^^^^^^^ help: call directly: `iter`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::into_iter_on_ref)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#into_iter_on_ref
[INFO] [stderr] 
[INFO] [stderr] warning: this .into_iter() call is equivalent to .iter() and will not move the slice
[INFO] [stderr]    --> src/expr_parser.rs:271:40
[INFO] [stderr]     |
[INFO] [stderr] 271 |         let mut it = tokens.as_slice().into_iter().peekable();
[INFO] [stderr]     |                                        ^^^^^^^^^ help: call directly: `iter`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#into_iter_on_ref
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]   --> src/stmt_parser.rs:24:5
[INFO] [stderr]    |
[INFO] [stderr] 24 | /     match peek(it)? {
[INFO] [stderr] 25 | |         &Token::Var => parse_var_declaration(it),
[INFO] [stderr] 26 | |         &Token::Fun => parse_function_declaration(it),
[INFO] [stderr] 27 | |         &Token::Class => parse_class_declaration(it),
[INFO] [stderr] 28 | |         _ => parse_statement(it),
[INFO] [stderr] 29 | |     }
[INFO] [stderr]    | |_____^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::match_ref_pats)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]    |
[INFO] [stderr] 24 |     match *(peek(it)?) {
[INFO] [stderr] 25 |         Token::Var => parse_var_declaration(it),
[INFO] [stderr] 26 |         Token::Fun => parse_function_declaration(it),
[INFO] [stderr] 27 |         Token::Class => parse_class_declaration(it),
[INFO] [stderr]    |
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]   --> src/stmt_parser.rs:36:5
[INFO] [stderr]    |
[INFO] [stderr] 36 | /     match peek(it)? {
[INFO] [stderr] 37 | |         &Token::Print => parse_print_statement(it),
[INFO] [stderr] 38 | |         &Token::If => parse_if_statement(it),
[INFO] [stderr] 39 | |         &Token::LeftBrace => parse_block_statement(it),
[INFO] [stderr] ...  |
[INFO] [stderr] 43 | |         _ => parse_expr_statement(it),
[INFO] [stderr] 44 | |     }
[INFO] [stderr]    | |_____^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]    |
[INFO] [stderr] 36 |     match *(peek(it)?) {
[INFO] [stderr] 37 |         Token::Print => parse_print_statement(it),
[INFO] [stderr] 38 |         Token::If => parse_if_statement(it),
[INFO] [stderr] 39 |         Token::LeftBrace => parse_block_statement(it),
[INFO] [stderr] 40 |         Token::While => parse_while_statement(it),
[INFO] [stderr] 41 |         Token::Return => parse_return_statement(it),
[INFO] [stderr]  ...
[INFO] [stderr] 
[INFO] [stderr] warning: `if _ { .. } else { .. }` is an expression
[INFO] [stderr]    --> src/stmt_parser.rs:117:5
[INFO] [stderr]     |
[INFO] [stderr] 117 | /     let mut initializer: Option<Expr> = None;
[INFO] [stderr] 118 | |
[INFO] [stderr] 119 | |     if optionally(it, &Token::Equal)? {
[INFO] [stderr] 120 | |         initializer = Some(parse_expr(it)?);
[INFO] [stderr] 121 | |     }
[INFO] [stderr]     | |_____^ help: it is more idiomatic to write: `let <mut> initializer = if optionally(it, &Token::Equal)? { Some(parse_expr(it)?) } else { None };`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::useless_let_if_seq)] on by default
[INFO] [stderr]     = note: you might not need `mut` at all
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#useless_let_if_seq
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]    --> src/stmt_parser.rs:141:23
[INFO] [stderr]     |
[INFO] [stderr] 141 |       let initializer = match peek(it)? {
[INFO] [stderr]     |  _______________________^
[INFO] [stderr] 142 | |         &Token::Var => Some(parse_var_declaration(it)?),
[INFO] [stderr] 143 | |         &Token::Semicolon => {
[INFO] [stderr] 144 | |             expect(it, &Token::Semicolon)?;
[INFO] [stderr] ...   |
[INFO] [stderr] 147 | |         _ => Some(parse_expr_statement(it)?),
[INFO] [stderr] 148 | |     };
[INFO] [stderr]     | |_____^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]     |
[INFO] [stderr] 141 |     let initializer = match *(peek(it)?) {
[INFO] [stderr] 142 |         Token::Var => Some(parse_var_declaration(it)?),
[INFO] [stderr] 143 |         Token::Semicolon => {
[INFO] [stderr]     |
[INFO] [stderr] 
[INFO] [stderr] warning: `if _ { .. } else { .. }` is an expression
[INFO] [stderr]    --> src/stmt_parser.rs:181:5
[INFO] [stderr]     |
[INFO] [stderr] 181 | /     let mut expr: Option<Expr> = None;
[INFO] [stderr] 182 | |     if peek(it)? != &Token::Semicolon {
[INFO] [stderr] 183 | |         expr = Some(parse_expr(it)?);
[INFO] [stderr] 184 | |     }
[INFO] [stderr]     | |_____^ help: it is more idiomatic to write: `let <mut> expr = if peek(it)? != &Token::Semicolon { Some(parse_expr(it)?) } else { None };`
[INFO] [stderr]     |
[INFO] [stderr]     = note: you might not need `mut` at all
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#useless_let_if_seq
[INFO] [stderr] 
[INFO] [stderr] warning: `if _ { .. } else { .. }` is an expression
[INFO] [stderr]    --> src/stmt_parser.rs:233:5
[INFO] [stderr]     |
[INFO] [stderr] 233 | /     let mut else_stmt: Option<Stmt> = None;
[INFO] [stderr] 234 | |
[INFO] [stderr] 235 | |     if optionally(it, &Token::Else)? {
[INFO] [stderr] 236 | |         else_stmt = Some(parse_statement(it)?);
[INFO] [stderr] 237 | |     }
[INFO] [stderr]     | |_____^ help: it is more idiomatic to write: `let <mut> else_stmt = if optionally(it, &Token::Else)? { Some(parse_statement(it)?) } else { None };`
[INFO] [stderr]     |
[INFO] [stderr]     = note: you might not need `mut` at all
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#useless_let_if_seq
[INFO] [stderr] 
[INFO] [stderr] warning: this .into_iter() call is equivalent to .iter() and will not move the slice
[INFO] [stderr]    --> src/stmt_parser.rs:269:40
[INFO] [stderr]     |
[INFO] [stderr] 269 |         let mut it = tokens.as_slice().into_iter().peekable();
[INFO] [stderr]     |                                        ^^^^^^^^^ help: call directly: `iter`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#into_iter_on_ref
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.79s
[INFO] running `"docker" "inspect" "4203ac6b8b582b00db3055ebbb80cface8268c4bf9971dce96a10d6db659a8f3"`
[INFO] running `"docker" "rm" "-f" "4203ac6b8b582b00db3055ebbb80cface8268c4bf9971dce96a10d6db659a8f3"`
[INFO] [stdout] 4203ac6b8b582b00db3055ebbb80cface8268c4bf9971dce96a10d6db659a8f3