diff options
Diffstat (limited to 'src/test/ui/pub')
36 files changed, 462 insertions, 0 deletions
diff --git a/src/test/ui/pub/issue-33174-restricted-type-in-public-interface.rs b/src/test/ui/pub/issue-33174-restricted-type-in-public-interface.rs new file mode 100644 index 000000000..67f888c5e --- /dev/null +++ b/src/test/ui/pub/issue-33174-restricted-type-in-public-interface.rs @@ -0,0 +1,28 @@ +#![allow(non_camel_case_types)] // genus is always capitalized + +pub(crate) struct Snail; +//~^ NOTE `Snail` declared as private + +mod sea { + pub(super) struct Turtle; + //~^ NOTE `Turtle` declared as crate-private +} + +struct Tortoise; +//~^ NOTE `Tortoise` declared as private + +pub struct Shell<T> { + pub(crate) creature: T, +} + +pub type Helix_pomatia = Shell<Snail>; +//~^ ERROR private type `Snail` in public interface +//~| NOTE can't leak private type +pub type Dermochelys_coriacea = Shell<sea::Turtle>; +//~^ ERROR crate-private type `Turtle` in public interface +//~| NOTE can't leak crate-private type +pub type Testudo_graeca = Shell<Tortoise>; +//~^ ERROR private type `Tortoise` in public interface +//~| NOTE can't leak private type + +fn main() {} diff --git a/src/test/ui/pub/issue-33174-restricted-type-in-public-interface.stderr b/src/test/ui/pub/issue-33174-restricted-type-in-public-interface.stderr new file mode 100644 index 000000000..39d4f5ac8 --- /dev/null +++ b/src/test/ui/pub/issue-33174-restricted-type-in-public-interface.stderr @@ -0,0 +1,30 @@ +error[E0446]: private type `Snail` in public interface + --> $DIR/issue-33174-restricted-type-in-public-interface.rs:18:1 + | +LL | pub(crate) struct Snail; + | ----------------------- `Snail` declared as private +... +LL | pub type Helix_pomatia = Shell<Snail>; + | ^^^^^^^^^^^^^^^^^^^^^^ can't leak private type + +error[E0446]: crate-private type `Turtle` in public interface + --> $DIR/issue-33174-restricted-type-in-public-interface.rs:21:1 + | +LL | pub(super) struct Turtle; + | ------------------------ `Turtle` declared as crate-private +... +LL | pub type Dermochelys_coriacea = Shell<sea::Turtle>; + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ can't leak crate-private type + +error[E0446]: private type `Tortoise` in public interface + --> $DIR/issue-33174-restricted-type-in-public-interface.rs:24:1 + | +LL | struct Tortoise; + | --------------- `Tortoise` declared as private +... +LL | pub type Testudo_graeca = Shell<Tortoise>; + | ^^^^^^^^^^^^^^^^^^^^^^^ can't leak private type + +error: aborting due to 3 previous errors + +For more information about this error, try `rustc --explain E0446`. diff --git a/src/test/ui/pub/pub-ident-fn-2.fixed b/src/test/ui/pub/pub-ident-fn-2.fixed new file mode 100644 index 000000000..afd75a41f --- /dev/null +++ b/src/test/ui/pub/pub-ident-fn-2.fixed @@ -0,0 +1,10 @@ +// run-rustfix + +pub fn foo(_s: usize) { bar() } +//~^ ERROR missing `fn` for function definition + +fn bar() {} + +fn main() { + foo(2); +} diff --git a/src/test/ui/pub/pub-ident-fn-2.rs b/src/test/ui/pub/pub-ident-fn-2.rs new file mode 100644 index 000000000..e7b86a909 --- /dev/null +++ b/src/test/ui/pub/pub-ident-fn-2.rs @@ -0,0 +1,10 @@ +// run-rustfix + +pub foo(_s: usize) { bar() } +//~^ ERROR missing `fn` for function definition + +fn bar() {} + +fn main() { + foo(2); +} diff --git a/src/test/ui/pub/pub-ident-fn-2.stderr b/src/test/ui/pub/pub-ident-fn-2.stderr new file mode 100644 index 000000000..b5b667b41 --- /dev/null +++ b/src/test/ui/pub/pub-ident-fn-2.stderr @@ -0,0 +1,13 @@ +error: missing `fn` for function definition + --> $DIR/pub-ident-fn-2.rs:3:4 + | +LL | pub foo(_s: usize) { bar() } + | ^ + | +help: add `fn` here to parse `foo` as a public function + | +LL | pub fn foo(_s: usize) { bar() } + | ++ + +error: aborting due to previous error + diff --git a/src/test/ui/pub/pub-ident-fn-3.rs b/src/test/ui/pub/pub-ident-fn-3.rs new file mode 100644 index 000000000..fdbea7cf4 --- /dev/null +++ b/src/test/ui/pub/pub-ident-fn-3.rs @@ -0,0 +1,8 @@ +// #60115 + +mod foo { + pub bar(); + //~^ ERROR missing `fn` or `struct` for function or struct definition +} + +fn main() {} diff --git a/src/test/ui/pub/pub-ident-fn-3.stderr b/src/test/ui/pub/pub-ident-fn-3.stderr new file mode 100644 index 000000000..6d3d4e592 --- /dev/null +++ b/src/test/ui/pub/pub-ident-fn-3.stderr @@ -0,0 +1,8 @@ +error: missing `fn` or `struct` for function or struct definition + --> $DIR/pub-ident-fn-3.rs:4:8 + | +LL | pub bar(); + | ---^--- help: if you meant to call a macro, try: `bar!` + +error: aborting due to previous error + diff --git a/src/test/ui/pub/pub-ident-fn-or-struct-2.rs b/src/test/ui/pub/pub-ident-fn-or-struct-2.rs new file mode 100644 index 000000000..8f67cdd29 --- /dev/null +++ b/src/test/ui/pub/pub-ident-fn-or-struct-2.rs @@ -0,0 +1,4 @@ +pub S(); +//~^ ERROR missing `fn` or `struct` for function or struct definition + +fn main() {} diff --git a/src/test/ui/pub/pub-ident-fn-or-struct-2.stderr b/src/test/ui/pub/pub-ident-fn-or-struct-2.stderr new file mode 100644 index 000000000..047e66b18 --- /dev/null +++ b/src/test/ui/pub/pub-ident-fn-or-struct-2.stderr @@ -0,0 +1,8 @@ +error: missing `fn` or `struct` for function or struct definition + --> $DIR/pub-ident-fn-or-struct-2.rs:1:4 + | +LL | pub S(); + | ---^- help: if you meant to call a macro, try: `S!` + +error: aborting due to previous error + diff --git a/src/test/ui/pub/pub-ident-fn-or-struct.rs b/src/test/ui/pub/pub-ident-fn-or-struct.rs new file mode 100644 index 000000000..832831d29 --- /dev/null +++ b/src/test/ui/pub/pub-ident-fn-or-struct.rs @@ -0,0 +1,4 @@ +pub S (foo) bar +//~^ ERROR missing `fn` or `struct` for function or struct definition + +fn main() {} diff --git a/src/test/ui/pub/pub-ident-fn-or-struct.stderr b/src/test/ui/pub/pub-ident-fn-or-struct.stderr new file mode 100644 index 000000000..c4a196eb2 --- /dev/null +++ b/src/test/ui/pub/pub-ident-fn-or-struct.stderr @@ -0,0 +1,8 @@ +error: missing `fn` or `struct` for function or struct definition + --> $DIR/pub-ident-fn-or-struct.rs:1:4 + | +LL | pub S (foo) bar + | ---^- help: if you meant to call a macro, try: `S!` + +error: aborting due to previous error + diff --git a/src/test/ui/pub/pub-ident-fn-with-lifetime-2.rs b/src/test/ui/pub/pub-ident-fn-with-lifetime-2.rs new file mode 100644 index 000000000..1ee8c84f1 --- /dev/null +++ b/src/test/ui/pub/pub-ident-fn-with-lifetime-2.rs @@ -0,0 +1,6 @@ +pub bar<'a>(&self, _s: &'a usize) -> bool { true } +//~^ ERROR missing `fn` for method definition + +fn main() { + bar(2); +} diff --git a/src/test/ui/pub/pub-ident-fn-with-lifetime-2.stderr b/src/test/ui/pub/pub-ident-fn-with-lifetime-2.stderr new file mode 100644 index 000000000..6a9aeaf4a --- /dev/null +++ b/src/test/ui/pub/pub-ident-fn-with-lifetime-2.stderr @@ -0,0 +1,13 @@ +error: missing `fn` for method definition + --> $DIR/pub-ident-fn-with-lifetime-2.rs:1:4 + | +LL | pub bar<'a>(&self, _s: &'a usize) -> bool { true } + | ^^^ + | +help: add `fn` here to parse `bar` as a public method + | +LL | pub fn bar<'a>(&self, _s: &'a usize) -> bool { true } + | ++ + +error: aborting due to previous error + diff --git a/src/test/ui/pub/pub-ident-fn-with-lifetime.fixed b/src/test/ui/pub/pub-ident-fn-with-lifetime.fixed new file mode 100644 index 000000000..e510ace5f --- /dev/null +++ b/src/test/ui/pub/pub-ident-fn-with-lifetime.fixed @@ -0,0 +1,8 @@ +// run-rustfix + +pub fn foo<'a>(_s: &'a usize) -> bool { true } +//~^ ERROR missing `fn` for function definition + +fn main() { + foo(&2); +} diff --git a/src/test/ui/pub/pub-ident-fn-with-lifetime.rs b/src/test/ui/pub/pub-ident-fn-with-lifetime.rs new file mode 100644 index 000000000..63e6eca15 --- /dev/null +++ b/src/test/ui/pub/pub-ident-fn-with-lifetime.rs @@ -0,0 +1,8 @@ +// run-rustfix + +pub foo<'a>(_s: &'a usize) -> bool { true } +//~^ ERROR missing `fn` for function definition + +fn main() { + foo(&2); +} diff --git a/src/test/ui/pub/pub-ident-fn-with-lifetime.stderr b/src/test/ui/pub/pub-ident-fn-with-lifetime.stderr new file mode 100644 index 000000000..c1ca0136b --- /dev/null +++ b/src/test/ui/pub/pub-ident-fn-with-lifetime.stderr @@ -0,0 +1,13 @@ +error: missing `fn` for function definition + --> $DIR/pub-ident-fn-with-lifetime.rs:3:4 + | +LL | pub foo<'a>(_s: &'a usize) -> bool { true } + | ^^^ + | +help: add `fn` here to parse `foo` as a public function + | +LL | pub fn foo<'a>(_s: &'a usize) -> bool { true } + | ++ + +error: aborting due to previous error + diff --git a/src/test/ui/pub/pub-ident-fn.fixed b/src/test/ui/pub/pub-ident-fn.fixed new file mode 100644 index 000000000..65ed8c7b4 --- /dev/null +++ b/src/test/ui/pub/pub-ident-fn.fixed @@ -0,0 +1,8 @@ +// run-rustfix + +pub fn foo(_s: usize) -> bool { true } +//~^ ERROR missing `fn` for function definition + +fn main() { + foo(2); +} diff --git a/src/test/ui/pub/pub-ident-fn.rs b/src/test/ui/pub/pub-ident-fn.rs new file mode 100644 index 000000000..2fe4d34fb --- /dev/null +++ b/src/test/ui/pub/pub-ident-fn.rs @@ -0,0 +1,8 @@ +// run-rustfix + +pub foo(_s: usize) -> bool { true } +//~^ ERROR missing `fn` for function definition + +fn main() { + foo(2); +} diff --git a/src/test/ui/pub/pub-ident-fn.stderr b/src/test/ui/pub/pub-ident-fn.stderr new file mode 100644 index 000000000..cb94c48ad --- /dev/null +++ b/src/test/ui/pub/pub-ident-fn.stderr @@ -0,0 +1,13 @@ +error: missing `fn` for function definition + --> $DIR/pub-ident-fn.rs:3:4 + | +LL | pub foo(_s: usize) -> bool { true } + | ^^^ + | +help: add `fn` here to parse `foo` as a public function + | +LL | pub fn foo(_s: usize) -> bool { true } + | ++ + +error: aborting due to previous error + diff --git a/src/test/ui/pub/pub-ident-struct-with-lifetime.rs b/src/test/ui/pub/pub-ident-struct-with-lifetime.rs new file mode 100644 index 000000000..2feb02660 --- /dev/null +++ b/src/test/ui/pub/pub-ident-struct-with-lifetime.rs @@ -0,0 +1,4 @@ +pub S<'a> { +//~^ ERROR missing `struct` for struct definition +} +fn main() {} diff --git a/src/test/ui/pub/pub-ident-struct-with-lifetime.stderr b/src/test/ui/pub/pub-ident-struct-with-lifetime.stderr new file mode 100644 index 000000000..562b68e35 --- /dev/null +++ b/src/test/ui/pub/pub-ident-struct-with-lifetime.stderr @@ -0,0 +1,13 @@ +error: missing `struct` for struct definition + --> $DIR/pub-ident-struct-with-lifetime.rs:1:4 + | +LL | pub S<'a> { + | ^ + | +help: add `struct` here to parse `S` as a public struct + | +LL | pub struct S<'a> { + | ++++++ + +error: aborting due to previous error + diff --git a/src/test/ui/pub/pub-ident-struct.fixed b/src/test/ui/pub/pub-ident-struct.fixed new file mode 100644 index 000000000..58cde8fd6 --- /dev/null +++ b/src/test/ui/pub/pub-ident-struct.fixed @@ -0,0 +1,6 @@ +// run-rustfix + +pub struct S { +//~^ ERROR missing `struct` for struct definition +} +fn main() {} diff --git a/src/test/ui/pub/pub-ident-struct.rs b/src/test/ui/pub/pub-ident-struct.rs new file mode 100644 index 000000000..3930e556e --- /dev/null +++ b/src/test/ui/pub/pub-ident-struct.rs @@ -0,0 +1,6 @@ +// run-rustfix + +pub S { +//~^ ERROR missing `struct` for struct definition +} +fn main() {} diff --git a/src/test/ui/pub/pub-ident-struct.stderr b/src/test/ui/pub/pub-ident-struct.stderr new file mode 100644 index 000000000..d3a378786 --- /dev/null +++ b/src/test/ui/pub/pub-ident-struct.stderr @@ -0,0 +1,13 @@ +error: missing `struct` for struct definition + --> $DIR/pub-ident-struct.rs:3:4 + | +LL | pub S { + | ^ + | +help: add `struct` here to parse `S` as a public struct + | +LL | pub struct S { + | ++++++ + +error: aborting due to previous error + diff --git a/src/test/ui/pub/pub-ident-with-lifetime-incomplete.rs b/src/test/ui/pub/pub-ident-with-lifetime-incomplete.rs new file mode 100644 index 000000000..c86a9f2fd --- /dev/null +++ b/src/test/ui/pub/pub-ident-with-lifetime-incomplete.rs @@ -0,0 +1,5 @@ +fn main() { +} + +pub foo<'a> +//~^ ERROR missing `fn` or `struct` for function or struct definition diff --git a/src/test/ui/pub/pub-ident-with-lifetime-incomplete.stderr b/src/test/ui/pub/pub-ident-with-lifetime-incomplete.stderr new file mode 100644 index 000000000..0e0b12705 --- /dev/null +++ b/src/test/ui/pub/pub-ident-with-lifetime-incomplete.stderr @@ -0,0 +1,8 @@ +error: missing `fn` or `struct` for function or struct definition + --> $DIR/pub-ident-with-lifetime-incomplete.rs:4:4 + | +LL | pub foo<'a> + | ^^^ + +error: aborting due to previous error + diff --git a/src/test/ui/pub/pub-reexport-priv-extern-crate.rs b/src/test/ui/pub/pub-reexport-priv-extern-crate.rs new file mode 100644 index 000000000..dd5cd420f --- /dev/null +++ b/src/test/ui/pub/pub-reexport-priv-extern-crate.rs @@ -0,0 +1,20 @@ +extern crate core; +pub use core as reexported_core; //~ ERROR `core` is private, and cannot be re-exported + //~^ WARN this was previously accepted + +mod foo1 { + extern crate core; +} + +mod foo2 { + use foo1::core; //~ ERROR crate import `core` is private + pub mod bar { + extern crate core; + } +} + +mod baz { + pub use foo2::bar::core; //~ ERROR crate import `core` is private +} + +fn main() {} diff --git a/src/test/ui/pub/pub-reexport-priv-extern-crate.stderr b/src/test/ui/pub/pub-reexport-priv-extern-crate.stderr new file mode 100644 index 000000000..e4d73c647 --- /dev/null +++ b/src/test/ui/pub/pub-reexport-priv-extern-crate.stderr @@ -0,0 +1,37 @@ +error[E0603]: crate import `core` is private + --> $DIR/pub-reexport-priv-extern-crate.rs:10:15 + | +LL | use foo1::core; + | ^^^^ private crate import + | +note: the crate import `core` is defined here + --> $DIR/pub-reexport-priv-extern-crate.rs:6:5 + | +LL | extern crate core; + | ^^^^^^^^^^^^^^^^^^ + +error[E0603]: crate import `core` is private + --> $DIR/pub-reexport-priv-extern-crate.rs:17:24 + | +LL | pub use foo2::bar::core; + | ^^^^ private crate import + | +note: the crate import `core` is defined here + --> $DIR/pub-reexport-priv-extern-crate.rs:12:9 + | +LL | extern crate core; + | ^^^^^^^^^^^^^^^^^^ + +error: extern crate `core` is private, and cannot be re-exported (error E0365), consider declaring with `pub` + --> $DIR/pub-reexport-priv-extern-crate.rs:2:9 + | +LL | pub use core as reexported_core; + | ^^^^^^^^^^^^^^^^^^^^^^^ + | + = note: `#[deny(pub_use_of_private_extern_crate)]` on by default + = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release! + = note: for more information, see issue #34537 <https://github.com/rust-lang/rust/issues/34537> + +error: aborting due to 3 previous errors + +For more information about this error, try `rustc --explain E0603`. diff --git a/src/test/ui/pub/pub-restricted-error-fn.rs b/src/test/ui/pub/pub-restricted-error-fn.rs new file mode 100644 index 000000000..fc1aeae2b --- /dev/null +++ b/src/test/ui/pub/pub-restricted-error-fn.rs @@ -0,0 +1,2 @@ +pub(crate) () fn foo() {} //~ ERROR visibility `pub(crate)` is not followed by an item +//~^ ERROR expected item, found `(` diff --git a/src/test/ui/pub/pub-restricted-error-fn.stderr b/src/test/ui/pub/pub-restricted-error-fn.stderr new file mode 100644 index 000000000..0511a821a --- /dev/null +++ b/src/test/ui/pub/pub-restricted-error-fn.stderr @@ -0,0 +1,16 @@ +error: visibility `pub(crate)` is not followed by an item + --> $DIR/pub-restricted-error-fn.rs:1:1 + | +LL | pub(crate) () fn foo() {} + | ^^^^^^^^^^ the visibility + | + = help: you likely meant to define an item, e.g., `pub(crate) fn foo() {}` + +error: expected item, found `(` + --> $DIR/pub-restricted-error-fn.rs:1:12 + | +LL | pub(crate) () fn foo() {} + | ^ expected item + +error: aborting due to 2 previous errors + diff --git a/src/test/ui/pub/pub-restricted-error.rs b/src/test/ui/pub/pub-restricted-error.rs new file mode 100644 index 000000000..60fce3f51 --- /dev/null +++ b/src/test/ui/pub/pub-restricted-error.rs @@ -0,0 +1,7 @@ +struct Bar(pub(())); + +struct Foo { + pub(crate) () foo: usize, //~ ERROR expected identifier +} + +fn main() {} diff --git a/src/test/ui/pub/pub-restricted-error.stderr b/src/test/ui/pub/pub-restricted-error.stderr new file mode 100644 index 000000000..95bf498c7 --- /dev/null +++ b/src/test/ui/pub/pub-restricted-error.stderr @@ -0,0 +1,8 @@ +error: expected identifier, found `(` + --> $DIR/pub-restricted-error.rs:4:16 + | +LL | pub(crate) () foo: usize, + | ^ expected identifier + +error: aborting due to previous error + diff --git a/src/test/ui/pub/pub-restricted-non-path.rs b/src/test/ui/pub/pub-restricted-non-path.rs new file mode 100644 index 000000000..bdad18dbe --- /dev/null +++ b/src/test/ui/pub/pub-restricted-non-path.rs @@ -0,0 +1,5 @@ +#![feature(pub_restricted)] + +pub (.) fn afn() {} //~ ERROR expected identifier + +fn main() {} diff --git a/src/test/ui/pub/pub-restricted-non-path.stderr b/src/test/ui/pub/pub-restricted-non-path.stderr new file mode 100644 index 000000000..e0ea50621 --- /dev/null +++ b/src/test/ui/pub/pub-restricted-non-path.stderr @@ -0,0 +1,8 @@ +error: expected identifier, found `.` + --> $DIR/pub-restricted-non-path.rs:3:6 + | +LL | pub (.) fn afn() {} + | ^ expected identifier + +error: aborting due to previous error + diff --git a/src/test/ui/pub/pub-restricted.rs b/src/test/ui/pub/pub-restricted.rs new file mode 100644 index 000000000..bcd21082f --- /dev/null +++ b/src/test/ui/pub/pub-restricted.rs @@ -0,0 +1,31 @@ +mod a {} + +pub (a) fn afn() {} //~ incorrect visibility restriction +pub (b) fn bfn() {} //~ incorrect visibility restriction +pub (crate::a) fn cfn() {} //~ incorrect visibility restriction + +pub fn privfn() {} +mod x { + mod y { + pub (in x) fn foo() {} + pub (super) fn bar() {} + pub (crate) fn qux() {} + } +} + +mod y { + struct Foo { + pub (crate) c: usize, + pub (super) s: usize, + valid_private: usize, + pub (in y) valid_in_x: usize, + pub (a) invalid: usize, //~ incorrect visibility restriction + pub (in x) non_parent_invalid: usize, //~ ERROR visibilities can only be restricted + } +} + +fn main() {} + +// test multichar names +mod xyz {} +pub (xyz) fn xyz() {} //~ incorrect visibility restriction diff --git a/src/test/ui/pub/pub-restricted.stderr b/src/test/ui/pub/pub-restricted.stderr new file mode 100644 index 000000000..4694530e5 --- /dev/null +++ b/src/test/ui/pub/pub-restricted.stderr @@ -0,0 +1,65 @@ +error[E0704]: incorrect visibility restriction + --> $DIR/pub-restricted.rs:3:6 + | +LL | pub (a) fn afn() {} + | ^ help: make this visible only to module `a` with `in`: `in a` + | + = help: some possible visibility restrictions are: + `pub(crate)`: visible only on the current crate + `pub(super)`: visible only in the current module's parent + `pub(in path::to::module)`: visible only on the specified path + +error[E0704]: incorrect visibility restriction + --> $DIR/pub-restricted.rs:4:6 + | +LL | pub (b) fn bfn() {} + | ^ help: make this visible only to module `b` with `in`: `in b` + | + = help: some possible visibility restrictions are: + `pub(crate)`: visible only on the current crate + `pub(super)`: visible only in the current module's parent + `pub(in path::to::module)`: visible only on the specified path + +error[E0704]: incorrect visibility restriction + --> $DIR/pub-restricted.rs:5:6 + | +LL | pub (crate::a) fn cfn() {} + | ^^^^^^^^ help: make this visible only to module `crate::a` with `in`: `in crate::a` + | + = help: some possible visibility restrictions are: + `pub(crate)`: visible only on the current crate + `pub(super)`: visible only in the current module's parent + `pub(in path::to::module)`: visible only on the specified path + +error[E0704]: incorrect visibility restriction + --> $DIR/pub-restricted.rs:22:14 + | +LL | pub (a) invalid: usize, + | ^ help: make this visible only to module `a` with `in`: `in a` + | + = help: some possible visibility restrictions are: + `pub(crate)`: visible only on the current crate + `pub(super)`: visible only in the current module's parent + `pub(in path::to::module)`: visible only on the specified path + +error[E0704]: incorrect visibility restriction + --> $DIR/pub-restricted.rs:31:6 + | +LL | pub (xyz) fn xyz() {} + | ^^^ help: make this visible only to module `xyz` with `in`: `in xyz` + | + = help: some possible visibility restrictions are: + `pub(crate)`: visible only on the current crate + `pub(super)`: visible only in the current module's parent + `pub(in path::to::module)`: visible only on the specified path + +error[E0742]: visibilities can only be restricted to ancestor modules + --> $DIR/pub-restricted.rs:23:17 + | +LL | pub (in x) non_parent_invalid: usize, + | ^ + +error: aborting due to 6 previous errors + +Some errors have detailed explanations: E0704, E0742. +For more information about an error, try `rustc --explain E0704`. |