From 6569a2ec1bef59bd409b13967278c95afb4bec28 Mon Sep 17 00:00:00 2001
From: Guillaume Gomez <guillaume1.gomez@gmail.com>
Date: Tue, 7 Apr 2020 14:07:57 +0200
Subject: Clean up E0507 explanation

---
 src/librustc_error_codes/error_codes/E0507.md | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

(limited to 'src/librustc_error_codes/error_codes')

diff --git a/src/librustc_error_codes/error_codes/E0507.md b/src/librustc_error_codes/error_codes/E0507.md
index 1e3457e96c5..254751fc45e 100644
--- a/src/librustc_error_codes/error_codes/E0507.md
+++ b/src/librustc_error_codes/error_codes/E0507.md
@@ -1,9 +1,4 @@
-You tried to move out of a value which was borrowed.
-
-This can also happen when using a type implementing `Fn` or `FnMut`, as neither
-allows moving out of them (they usually represent closures which can be called
-more than once). Much of the text following applies equally well to non-`FnOnce`
-closure bodies.
+A borrowed value was moved out.
 
 Erroneous code example:
 
@@ -32,6 +27,11 @@ you have three choices:
 * Somehow reclaim the ownership.
 * Implement the `Copy` trait on the type.
 
+This can also happen when using a type implementing `Fn` or `FnMut`, as neither
+allows moving out of them (they usually represent closures which can be called
+more than once). Much of the text following applies equally well to non-`FnOnce`
+closure bodies.
+
 Examples:
 
 ```
-- 
cgit 1.4.1-3-g733a5


From 80e3126ec1134d81dca7c698d88156307a50a3ba Mon Sep 17 00:00:00 2001
From: Guillaume Gomez <guillaume1.gomez@gmail.com>
Date: Wed, 8 Apr 2020 15:05:52 +0200
Subject: Clean up E0510 explanation

---
 src/librustc_error_codes/error_codes/E0510.md | 27 ++++++++++++++++++++-------
 1 file changed, 20 insertions(+), 7 deletions(-)

(limited to 'src/librustc_error_codes/error_codes')

diff --git a/src/librustc_error_codes/error_codes/E0510.md b/src/librustc_error_codes/error_codes/E0510.md
index d5be417888b..e045e04bdbe 100644
--- a/src/librustc_error_codes/error_codes/E0510.md
+++ b/src/librustc_error_codes/error_codes/E0510.md
@@ -1,16 +1,29 @@
-Cannot mutate place in this match guard.
+The matched value was assigned in a match guard.
 
-When matching on a variable it cannot be mutated in the match guards, as this
-could cause the match to be non-exhaustive:
+Erroneous code example:
 
 ```compile_fail,E0510
 let mut x = Some(0);
 match x {
-    None => (),
-    Some(_) if { x = None; false } => (),
-    Some(v) => (), // No longer matches
+    None => {}
+    Some(_) if { x = None; false } => {} // error!
+    Some(_) => {}
 }
 ```
 
+When matching on a variable it cannot be mutated in the match guards, as this
+could cause the match to be non-exhaustive.
+
 Here executing `x = None` would modify the value being matched and require us
-to go "back in time" to the `None` arm.
+to go "back in time" to the `None` arm. To fix it, change the value in the match
+arm:
+
+```
+let mut x = Some(0);
+match x {
+    None => {}
+    Some(_) => {
+        x = None; // ok!
+    }
+}
+```
-- 
cgit 1.4.1-3-g733a5