From 9c6c2f16f00ed6f24866d2d4927b49d79b453a23 Mon Sep 17 00:00:00 2001
From: Guillaume Gomez <guillaume1.gomez@gmail.com>
Date: Thu, 16 Jan 2020 14:35:37 +0100
Subject: Clean up E0198 explanation

---
 src/librustc_error_codes/error_codes/E0198.md | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

(limited to 'src/librustc_error_codes/error_codes')

diff --git a/src/librustc_error_codes/error_codes/E0198.md b/src/librustc_error_codes/error_codes/E0198.md
index 6504d60dbd1..687214a2050 100644
--- a/src/librustc_error_codes/error_codes/E0198.md
+++ b/src/librustc_error_codes/error_codes/E0198.md
@@ -1,17 +1,18 @@
-A negative implementation is one that excludes a type from implementing a
-particular trait. Not being able to use a trait is always a safe operation,
-so negative implementations are always safe and never need to be marked as
-unsafe.
+A negative implementation was marked as unsafe.
 
-```compile_fail
-#![feature(optin_builtin_traits)]
+Erroneous code example:
 
+```compile_fail
 struct Foo;
 
-// unsafe is unnecessary
-unsafe impl !Clone for Foo { }
+unsafe impl !Clone for Foo { } // error!
 ```
 
+A negative implementation is one that excludes a type from implementing a
+particular trait. Not being able to use a trait is always a safe operation,
+so negative implementations are always safe and never need to be marked as
+unsafe.
+
 This will compile:
 
 ```ignore (ignore auto_trait future compatibility warning)
-- 
cgit 1.4.1-3-g733a5


From e8a4b9319cbf5b3f56b3cdd8ad11e86ff7168345 Mon Sep 17 00:00:00 2001
From: Guillaume Gomez <guillaume1.gomez@gmail.com>
Date: Fri, 17 Jan 2020 19:54:07 +0100
Subject: Clean up E0199 explanation

---
 src/librustc_error_codes/error_codes/E0199.md | 21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

(limited to 'src/librustc_error_codes/error_codes')

diff --git a/src/librustc_error_codes/error_codes/E0199.md b/src/librustc_error_codes/error_codes/E0199.md
index d0c12dc6f17..88130e8e5e5 100644
--- a/src/librustc_error_codes/error_codes/E0199.md
+++ b/src/librustc_error_codes/error_codes/E0199.md
@@ -1,14 +1,23 @@
+A trait implementation was marked as unsafe while the trait is safe.
+
+Erroneous code example:
+
+```compile_fail,E0199
+struct Foo;
+
+trait Bar { }
+
+unsafe impl Bar for Foo { } // error!
+```
+
 Safe traits should not have unsafe implementations, therefore marking an
 implementation for a safe trait unsafe will cause a compiler error. Removing
-the unsafe marker on the trait noted in the error will resolve this problem.
+the unsafe marker on the trait noted in the error will resolve this problem:
 
-```compile_fail,E0199
+```
 struct Foo;
 
 trait Bar { }
 
-// this won't compile because Bar is safe
-unsafe impl Bar for Foo { }
-// this will compile
-impl Bar for Foo { }
+impl Bar for Foo { } // ok!
 ```
-- 
cgit 1.4.1-3-g733a5