(
Some(ref name),
BorrowExplanation::MustBeValidFor {
- category: category @ ConstraintCategory::Return,
+ category:
+ category
+ @
+ (ConstraintCategory::Return
+ | ConstraintCategory::CallArgument
+ | ConstraintCategory::OpaqueType),
from_closure: false,
ref region_name,
span,
..
},
- )
- | (
- Some(ref name),
- BorrowExplanation::MustBeValidFor {
- category: category @ ConstraintCategory::CallArgument,
- from_closure: false,
- ref region_name,
- span,
- ..
- },
- ) if borrow_spans.for_closure() => self.report_escaping_closure_capture(
- borrow_spans,
- borrow_span,
- region_name,
- category,
- span,
- &format!("`{}`", name),
- ),
- (
- Some(ref name),
- BorrowExplanation::MustBeValidFor {
- category: category @ ConstraintCategory::OpaqueType,
- from_closure: false,
- ref region_name,
+ ) if borrow_spans.for_generator() | borrow_spans.for_closure() => self
+ .report_escaping_closure_capture(
+ borrow_spans,
+ borrow_span,
+ region_name,
+ category,
span,
- ..
- },
- ) if borrow_spans.for_generator() => self.report_escaping_closure_capture(
- borrow_spans,
- borrow_span,
- region_name,
- category,
- span,
- &format!("`{}`", name),
- ),
+ &format!("`{}`", name),
+ ),
(
ref name,
BorrowExplanation::MustBeValidFor {
) -> DiagnosticBuilder<'cx> {
let tcx = self.infcx.tcx;
let args_span = use_span.args_or_use();
- let mut err = self.cannot_capture_in_long_lived_closure(args_span, captured_var, var_span);
let suggestion = match tcx.sess.source_map().span_to_snippet(args_span) {
Ok(mut string) => {
},
None => "closure",
};
+
+ let mut err =
+ self.cannot_capture_in_long_lived_closure(args_span, kind, captured_var, var_span);
err.span_suggestion(
args_span,
&format!(
);
let msg = match category {
- ConstraintCategory::Return => "closure is returned here".to_string(),
- ConstraintCategory::OpaqueType => "generator is returned here".to_string(),
+ ConstraintCategory::Return | ConstraintCategory::OpaqueType => {
+ format!("{} is returned here", kind)
+ }
ConstraintCategory::CallArgument => {
fr_name.highlight_region_name(&mut err);
format!("function requires argument type to outlive `{}`", fr_name)
#![feature(stmt_expr_attributes)]
#![feature(trait_alias)]
#![feature(option_expect_none)]
+#![feature(or_patterns)]
#![recursion_limit = "256"]
#[macro_use]
crate fn cannot_capture_in_long_lived_closure(
&self,
closure_span: Span,
+ closure_kind: &str,
borrowed_path: &str,
capture_span: Span,
) -> DiagnosticBuilder<'cx> {
self,
closure_span,
E0373,
- "closure may outlive the current function, \
+ "{} may outlive the current function, \
but it borrows {}, \
which is owned by the current function",
+ closure_kind,
borrowed_path,
);
err.span_label(capture_span, format!("{} is borrowed here", borrowed_path))
// edition:2018
// run-rustfix
-fn foo() -> Box<impl std::future::Future<Output = u32>> {
+fn test_boxed() -> Box<impl std::future::Future<Output = u32>> {
let x = 0u32;
Box::new(async move { x } )
//~^ ERROR E0373
}
+fn test_ref(x: &u32) -> impl std::future::Future<Output = u32> + '_ {
+ async move { *x }
+ //~^ ERROR E0373
+}
+
fn main() {
- let _foo = foo();
+ let _ = test_boxed();
+ let _ = test_ref(&0u32);
}
// edition:2018
// run-rustfix
-fn foo() -> Box<impl std::future::Future<Output = u32>> {
+fn test_boxed() -> Box<impl std::future::Future<Output = u32>> {
let x = 0u32;
Box::new(async { x } )
//~^ ERROR E0373
}
+fn test_ref(x: &u32) -> impl std::future::Future<Output = u32> + '_ {
+ async { *x }
+ //~^ ERROR E0373
+}
+
fn main() {
- let _foo = foo();
+ let _ = test_boxed();
+ let _ = test_ref(&0u32);
}
-error[E0373]: closure may outlive the current function, but it borrows `x`, which is owned by the current function
+error[E0373]: async block may outlive the current function, but it borrows `x`, which is owned by the current function
--> $DIR/async-borrowck-escaping-block-error.rs:6:20
|
LL | Box::new(async { x } )
| | `x` is borrowed here
| may outlive borrowed value `x`
|
-note: generator is returned here
- --> $DIR/async-borrowck-escaping-block-error.rs:4:13
+note: async block is returned here
+ --> $DIR/async-borrowck-escaping-block-error.rs:4:20
|
-LL | fn foo() -> Box<impl std::future::Future<Output = u32>> {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | fn test_boxed() -> Box<impl std::future::Future<Output = u32>> {
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
help: to force the async block to take ownership of `x` (and any other referenced variables), use the `move` keyword
|
LL | Box::new(async move { x } )
| ^^^^^^^^^^
-error: aborting due to previous error
+error[E0373]: async block may outlive the current function, but it borrows `x`, which is owned by the current function
+ --> $DIR/async-borrowck-escaping-block-error.rs:11:11
+ |
+LL | async { *x }
+ | ^^^-^^
+ | | |
+ | | `x` is borrowed here
+ | may outlive borrowed value `x`
+ |
+note: async block is returned here
+ --> $DIR/async-borrowck-escaping-block-error.rs:11:5
+ |
+LL | async { *x }
+ | ^^^^^^^^^^^^
+help: to force the async block to take ownership of `x` (and any other referenced variables), use the `move` keyword
+ |
+LL | async move { *x }
+ | ^^^^^^^^^^^
+
+error: aborting due to 2 previous errors
For more information about this error, try `rustc --explain E0373`.
// edition:2018
-#![feature(async_closure,async_await)]
+#![feature(async_closure)]
fn foo() -> Box<dyn std::future::Future<Output = u32>> {
let x = 0u32;
Box::new((async || x)())
impl List {
fn started_with<'a>(&'a self, prefix: &'a str) -> impl Iterator<Item=&'a str> {
self.data.iter().filter(|s| s.starts_with(prefix)).map(|s| s.as_ref())
- //~^ ERROR does not live long enough
+ //~^ ERROR E0373
}
}
-error[E0597]: `prefix` does not live long enough
- --> $DIR/does-not-live-long-enough.rs:6:51
+error[E0373]: closure may outlive the current function, but it borrows `prefix`, which is owned by the current function
+ --> $DIR/does-not-live-long-enough.rs:6:33
|
-LL | fn started_with<'a>(&'a self, prefix: &'a str) -> impl Iterator<Item=&'a str> {
- | -- lifetime `'a` defined here --------------------------- opaque type requires that `prefix` is borrowed for `'a`
LL | self.data.iter().filter(|s| s.starts_with(prefix)).map(|s| s.as_ref())
- | --- ^^^^^^ borrowed value does not live long enough
+ | ^^^ ------ `prefix` is borrowed here
| |
- | value captured here
-LL |
-LL | }
- | - `prefix` dropped here while still borrowed
+ | may outlive borrowed value `prefix`
+ |
+note: closure is returned here
+ --> $DIR/does-not-live-long-enough.rs:5:55
|
-help: you can add a bound to the opaque type to make it last less than `'static` and match `'a`
+LL | fn started_with<'a>(&'a self, prefix: &'a str) -> impl Iterator<Item=&'a str> {
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+help: to force the closure to take ownership of `prefix` (and any other referenced variables), use the `move` keyword
|
-LL | fn started_with<'a>(&'a self, prefix: &'a str) -> impl Iterator<Item=&'a str> + 'a {
- | ^^^^
+LL | self.data.iter().filter(move |s| s.starts_with(prefix)).map(|s| s.as_ref())
+ | ^^^^^^^^
error: aborting due to previous error
-For more information about this error, try `rustc --explain E0597`.
+For more information about this error, try `rustc --explain E0373`.
projects / rust.git / commitdiff