diff options
Diffstat (limited to '')
| -rw-r--r-- | src/doc/reference/src/expressions/block-expr.md | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/src/doc/reference/src/expressions/block-expr.md b/src/doc/reference/src/expressions/block-expr.md index a68b27e56..bd9c0a623 100644 --- a/src/doc/reference/src/expressions/block-expr.md +++ b/src/doc/reference/src/expressions/block-expr.md @@ -103,7 +103,7 @@ Async contexts are established by async blocks as well as the bodies of async fu Async blocks act like a function boundary, much like closures. Therefore, the `?` operator and `return` expressions both affect the output of the future, not the enclosing function or other context. -That is, `return <expr>` from within a closure will return the result of `<expr>` as the output of the future. +That is, `return <expr>` from within an async block will return the result of `<expr>` as the output of the future. Similarly, if `<expr>?` propagates an error, that error is propagated as the result of the future. Finally, the `break` and `continue` keywords cannot be used to branch out from an async block. @@ -112,7 +112,7 @@ Therefore the following is illegal: ```rust,compile_fail loop { async move { - break; // This would break out of the loop. + break; // error[E0267]: `break` inside of an `async` block } } ``` @@ -140,6 +140,10 @@ unsafe { let a = unsafe { an_unsafe_fn() }; ``` +## Labelled block expressions + +Labelled block expressions are documented in the [Loops and other breakable expressions] section. + ## Attributes on block expressions [Inner attributes] are allowed directly after the opening brace of a block expression in the following situations: @@ -189,3 +193,4 @@ fn is_unix_platform() -> bool { [tuple expressions]: tuple-expr.md [unsafe operations]: ../unsafety.md [value expressions]: ../expressions.md#place-expressions-and-value-expressions +[Loops and other breakable expressions]: loop-expr.md#labelled-block-expressions |