From e0ecfc83b738e2c4ca0e6aee1528000e811997f8 Mon Sep 17 00:00:00 2001
From: hsutter <herb.sutter@gmail.com>
Date: Mon, 18 Jun 2018 11:47:53 -0700
Subject: [PATCH] Closes 1220

---
 CppCoreGuidelines.md | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/CppCoreGuidelines.md b/CppCoreGuidelines.md
index f58e752..d2c0097 100644
--- a/CppCoreGuidelines.md
+++ b/CppCoreGuidelines.md
@@ -1312,6 +1312,10 @@ You cannot have a race condition on immutable data.
 
 **References**: See the [rules for calling functions](#SS-call).
 
+##### Note
+
+The rule is "avoid", not "don't use." Of course there will be (rare) exceptions, such as `cin`, `cout`, and `cerr`.
+
 ##### Enforcement
 
 (Simple) Report all non-`const` variables declared at namespace scope.