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-rw-r--r--tests/ui/consts/const-try.rs39
1 files changed, 39 insertions, 0 deletions
diff --git a/tests/ui/consts/const-try.rs b/tests/ui/consts/const-try.rs
new file mode 100644
index 00000000000..e199fd9ff8a
--- /dev/null
+++ b/tests/ui/consts/const-try.rs
@@ -0,0 +1,39 @@
+// check-pass
+
+// Demonstrates what's needed to make use of `?` in const contexts.
+
+#![crate_type = "lib"]
+#![feature(try_trait_v2)]
+#![feature(const_trait_impl)]
+#![feature(const_try)]
+
+use std::ops::{ControlFlow, FromResidual, Try};
+
+struct TryMe;
+struct Error;
+
+impl const FromResidual<Error> for TryMe {
+    fn from_residual(residual: Error) -> Self {
+        TryMe
+    }
+}
+
+impl const Try for TryMe {
+    type Output = ();
+    type Residual = Error;
+    fn from_output(output: Self::Output) -> Self {
+        TryMe
+    }
+    fn branch(self) -> ControlFlow<Self::Residual, Self::Output> {
+        ControlFlow::Break(Error)
+    }
+}
+
+const fn t() -> TryMe {
+    TryMe?;
+    TryMe
+}
+
+const _: () = {
+    t();
+};