From 23cc0d1a3883ceeb5af77d644b32895b399b740e Mon Sep 17 00:00:00 2001
From: Stephen Brawner <brawner@gmail.com>
Date: Fri, 8 Jan 2021 14:59:55 -0800
Subject: [PATCH] Update Migration.md

---
 Migration.md | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/Migration.md b/Migration.md
index bffce89e8..079e733a6 100644
--- a/Migration.md
+++ b/Migration.md
@@ -23,6 +23,13 @@ but with improved human-readability..
 1. **sdf/Model.hh**:
     + std::pair<const Link *, std::string> CanonicalLinkAndRelativeName() const;
 
+1. **sdf/Root.hh** sdf::Root elements can now only contain one of either Model,
+      Light or Actor since multiple items would conflict with overrides
+      specified in an <include> tag.
+    + const sdf::Model \*Model();
+    + const sdf::Light \*Light();
+    + const sdf::Actor \*Actor();
+
 ### Modifications
 
 1. **sdf/Model.hh**: the following methods now accept nested names relative to
@@ -36,6 +43,21 @@ but with improved human-readability..
     + bool JointNameExists(const std::string &) const
     + bool LinkNameExists(const std::string &) const
 
+### Deprecations
+
+1. **src/Root.hh**: The following methods have been deprecated in favor of the
+      new methods. For now the behavior is unchanged, but Root elements should
+      only contain one or none of Model/Light/Actor.
+    + const sdf::Model \*ModelByIndex();
+    + uint64_t ModelCount();
+    + bool ModelNameExists(const std::string &\_name) const;
+    + const sdf::Light \*LightByIndex();
+    + uint64_t LightCount();
+    + bool LightNameExists(const std::string &\_name) const;
+    + const sdf::Actor \*ActorByIndex();
+    + uint64_t ActorCount();
+    + bool ActorNameExists(const std::string &\_name) const;
+
 ## SDFormat 9.x to 10.0
 
 ### Modifications