diff --git a/src/libstd/process.rs b/src/libstd/process.rs index e25599b8bd871..e5fc33e241c89 100644 --- a/src/libstd/process.rs +++ b/src/libstd/process.rs @@ -1080,6 +1080,15 @@ impl fmt::Display for ExitStatus { } } +/// This is ridiculously unstable, as it's a completely-punted-upon part +/// of the `?`-in-`main` RFC. It's here only to allow experimenting with +/// returning a code directly from main. It will definitely change +/// drastically before being stabilized, if it doesn't just get deleted. +#[doc(hidden)] +#[derive(Clone, Copy, Debug)] +#[unstable(feature = "process_exitcode_placeholder", issue = "43301")] +pub struct ExitCode(pub i32); + impl Child { /// Forces the child to exit. This is equivalent to sending a /// SIGKILL on unix platforms. @@ -1428,7 +1437,7 @@ impl Termination for () { } #[unstable(feature = "termination_trait_lib", issue = "43301")] -impl Termination for Result { +impl Termination for Result<(), E> { fn report(self) -> i32 { match self { Ok(val) => val.report(), @@ -1442,20 +1451,23 @@ impl Termination for Result { #[unstable(feature = "termination_trait_lib", issue = "43301")] impl Termination for ! { - fn report(self) -> i32 { unreachable!(); } + fn report(self) -> i32 { self } } #[unstable(feature = "termination_trait_lib", issue = "43301")] -impl Termination for bool { +impl Termination for Result { fn report(self) -> i32 { - if self { exit::SUCCESS } else { exit::FAILURE } + let Err(err) = self; + eprintln!("Error: {:?}", err); + exit::FAILURE } } #[unstable(feature = "termination_trait_lib", issue = "43301")] -impl Termination for i32 { +impl Termination for ExitCode { fn report(self) -> i32 { - self + let ExitCode(code) = self; + code } } diff --git a/src/test/run-pass/rfc-1937-termination-trait/termination-trait-for-i32.rs b/src/test/run-pass/rfc-1937-termination-trait/termination-trait-for-exitcode.rs similarity index 81% rename from src/test/run-pass/rfc-1937-termination-trait/termination-trait-for-i32.rs rename to src/test/run-pass/rfc-1937-termination-trait/termination-trait-for-exitcode.rs index fa7cb023b447c..30ecc4e89372b 100644 --- a/src/test/run-pass/rfc-1937-termination-trait/termination-trait-for-i32.rs +++ b/src/test/run-pass/rfc-1937-termination-trait/termination-trait-for-exitcode.rs @@ -9,7 +9,10 @@ // except according to those terms. #![feature(termination_trait)] +#![feature(process_exitcode_placeholder)] -fn main() -> i32 { - 0 +use std::process::ExitCode; + +fn main() -> ExitCode { + ExitCode(0) }