From: Corey Farwell <coreyf@rwell.org>
Date: Wed, 11 Jul 2018 02:25:38 +0000 (-0400)
Subject: Avoid unwrapping in PanicInfo doc example.
X-Git-Url: https://git.lizzy.rs/?a=commitdiff_plain;h=d2fb2fb2a5f58839eda54e5f347e0959ed6eec7c;p=rust.git

Avoid unwrapping in PanicInfo doc example.

Fixes https://github.com/rust-lang/rust/issues/51768.
---

diff --git a/src/libcore/panic.rs b/src/libcore/panic.rs
index 1b4129b99fc..10f02ca2fdc 100644
--- a/src/libcore/panic.rs
+++ b/src/libcore/panic.rs
@@ -30,7 +30,11 @@
 /// use std::panic;
 ///
 /// panic::set_hook(Box::new(|panic_info| {
-///     println!("panic occurred: {:?}", panic_info.payload().downcast_ref::<&str>().unwrap());
+///     if let Some(s) = panic_info.payload().downcast_ref::<&str>() {
+///         println!("panic occurred: {:?}", s);
+///     } else {
+///         println!("panic occurred");
+///     }
 /// }));
 ///
 /// panic!("Normal panic");