doc/go1.18: document union element restriction

For #47694

Change-Id: I9af871a4a45b002e72629904011aac8f076617f1
Reviewed-on: https://go-review.googlesource.com/c/go/+/372974
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>

diff --git a/doc/go1.18.html b/doc/go1.18.html
index 2ec5fae8c782f155d85cf89c33bad1f0366ea058..5f6476908aa71cf1fab2c77f7faadff4c8c0c4f5 100644 (file)
--- a/doc/go1.18.html
+++ b/doc/go1.18.html
@@ -103,6 +103,11 @@ Do not send CLs removing the interior tags from such phrases.
       embedding a type parameter in an interface type is not permitted.
       Whether these will ever be permitted is unclear at present.
     </li>
+    <li>
+      A union element with more than one term may not contain an
+      interface type with a non-empty method set. Whether this will
+      ever be permitted is unclear at present.
+    </li>
   </ul>
 </p>