From a45c8b09e86ea4eed283a6163b44c493d15ee5c3 Mon Sep 17 00:00:00 2001
From: Lee Bousfield <ljbousfield@gmail.com>
Date: Mon, 10 Jul 2017 20:18:36 -0400
Subject: [PATCH] Use LocalKey::try_with in std

---
 src/libstd/io/stdio.rs               | 22 ++++++++--------------
 src/libstd/sys_common/thread_info.rs | 11 +++--------
 2 files changed, 11 insertions(+), 22 deletions(-)

diff --git a/src/libstd/io/stdio.rs b/src/libstd/io/stdio.rs
index fb489bf487b..d71fa133454 100644
--- a/src/libstd/io/stdio.rs
+++ b/src/libstd/io/stdio.rs
@@ -17,7 +17,7 @@ use io::{self, Initializer, BufReader, LineWriter};
 use sync::{Arc, Mutex, MutexGuard};
 use sys::stdio;
 use sys_common::remutex::{ReentrantMutex, ReentrantMutexGuard};
-use thread::{LocalKey, LocalKeyState};
+use thread::LocalKey;
 
 /// Stdout used by print! and println! macros
 thread_local! {
@@ -674,20 +674,14 @@ fn print_to<T>(args: fmt::Arguments,
                local_s: &'static LocalKey<RefCell<Option<Box<Write+Send>>>>,
                global_s: fn() -> T,
                label: &str) where T: Write {
-    let result = match local_s.state() {
-        LocalKeyState::Uninitialized |
-        LocalKeyState::Destroyed => global_s().write_fmt(args),
-        LocalKeyState::Valid => {
-            local_s.with(|s| {
-                if let Ok(mut borrowed) = s.try_borrow_mut() {
-                    if let Some(w) = borrowed.as_mut() {
-                        return w.write_fmt(args);
-                    }
-                }
-                global_s().write_fmt(args)
-            })
+    let result = local_s.try_with(|s| {
+        if let Ok(mut borrowed) = s.try_borrow_mut() {
+            if let Some(w) = borrowed.as_mut() {
+                return w.write_fmt(args);
+            }
         }
-    };
+        global_s().write_fmt(args)
+    }).unwrap_or_else(|_| global_s().write_fmt(args));
     if let Err(e) = result {
         panic!("failed printing to {}: {}", label, e);
     }
diff --git a/src/libstd/sys_common/thread_info.rs b/src/libstd/sys_common/thread_info.rs
index 5ed48ee4558..2abb8afa828 100644
--- a/src/libstd/sys_common/thread_info.rs
+++ b/src/libstd/sys_common/thread_info.rs
@@ -12,7 +12,6 @@
 
 use cell::RefCell;
 use thread::Thread;
-use thread::LocalKeyState;
 
 struct ThreadInfo {
     stack_guard: Option<usize>,
@@ -23,19 +22,15 @@ thread_local! { static THREAD_INFO: RefCell<Option<ThreadInfo>> = RefCell::new(N
 
 impl ThreadInfo {
     fn with<R, F>(f: F) -> Option<R> where F: FnOnce(&mut ThreadInfo) -> R {
-        if THREAD_INFO.state() == LocalKeyState::Destroyed {
-            return None
-        }
-
-        THREAD_INFO.with(move |c| {
+        THREAD_INFO.try_with(move |c| {
             if c.borrow().is_none() {
                 *c.borrow_mut() = Some(ThreadInfo {
                     stack_guard: None,
                     thread: Thread::new(None),
                 })
             }
-            Some(f(c.borrow_mut().as_mut().unwrap()))
-        })
+            f(c.borrow_mut().as_mut().unwrap())
+        }).ok()
     }
 }