Repository navigation
try $body:block in a macro is not recognized as a try block #112952
Description
#![feature(try_blocks)]
macro_rules! create_try {
($body:block) => {
try $body
};
}
fn main() {
let x: Option<&str> = create_try! {{
None?;
"Hello world"
}};
println!("{x:?}");
}I expected to see this happen:
None
Instead, this happened:
error: expected expression, found reserved keyword `try`
--> src/main.rs:6:9
|
6 | try $body
| ^^^ expected expression
...
11 | let x: Option<&str> = create_try! {{
| ___________________________-
12 | | None?;
13 | | "Hello world"
14 | | }};
| |______- in this macro invocation
|
= note: this error originates in the macro `create_try` (in Nightly builds, run with -Z macro-backtrace for more info)
Note that this works fine for similar expressions, such as if expressions:
macro_rules! create_if {
($body:block) => {
if true $body else { unreachable!(); }
};
}
fn main() {
let x: &str = create_if! {{
"Hello world"
}};
println!("{x:?}");
}"Hello world"
Meta
rustc --version --verbose:
rustc 1.71.0-nightly (9d871b061 2023-05-21)
binary: rustc
commit-hash: 9d871b0617a4b3d6610b7cee0ab5310dcb542c62
commit-date: 2023-05-21
host: x86_64-unknown-linux-gnu
release: 1.71.0-nightly
LLVM version: 16.0.4
Also reproduces on nightly 1.72.0-nightly (2023-06-21 065a1f5df9c2f1d93269) (tested on the playground)
@rustbot modify labels +A-macros +F-try_blocks
Activity
compiler-errors commentedon Jun 23, 2023
We don't support, for example,
unsafe $block, so this probably needs to go by T-lang.Auto merge of rust-lang#112953 - compiler-errors:interpolated-block-e…