Implement Error for !.

rust-lang · Mar 16, 2017 · a5cf551 · a5cf551
1 parent 11a3376
commit a5cf551
Show file tree

Hide file tree

Showing 2 changed files with 6 additions and 0 deletions.
diff --git a/src/libstd/error.rs b/src/libstd/error.rs
@@ -216,6 +216,11 @@ impl<'a> From<&'a str> for Box<Error> {
     }
 }
 
+#[stable(feature = "never_error", since = "1.18.0")]
+impl Error for ! {
+    fn description(&self) -> &str { *self }
+}
+
 #[stable(feature = "rust1", since = "1.0.0")]
 impl Error for str::ParseBoolError {
     fn description(&self) -> &str { "failed to parse bool" }

diff --git a/src/libstd/lib.rs b/src/libstd/lib.rs
@@ -273,6 +273,7 @@
 #![feature(linkage)]
 #![feature(macro_reexport)]
 #![feature(needs_panic_runtime)]
+#![feature(never_type)]
 #![feature(num_bits_bytes)]
 #![feature(old_wrapping)]
 #![feature(on_unimplemented)]