From f882f4b065199c3618087e3abc7d07af7e0dd6b0 Mon Sep 17 00:00:00 2001
From: Alessio Quaglino <quaglino@google.com>
Date: Thu, 5 Dec 2024 03:18:51 -0800
Subject: [PATCH] Remove requirement to specify a name prefix or suffix during
 attach.

PiperOrigin-RevId: 703049862
Change-Id: I5fd6da0581331b1b716110292a8160ae16934157
---
 src/user/user_objects.cc | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/src/user/user_objects.cc b/src/user/user_objects.cc
index 3e4c61bf..9654182c 100644
--- a/src/user/user_objects.cc
+++ b/src/user/user_objects.cc
@@ -873,10 +873,6 @@ mjCBody& mjCBody::operator+=(const mjCFrame& other) {
   other.model->suffix = other.suffix;
   other.model->StoreKeyframes(model);
 
-  if (other.prefix.empty() && other.suffix.empty()) {
-    throw mjCError(this, "either prefix or suffix must be non-empty");
-  }
-
   // attach defaults
   if (other.model != model) {
     mjCDef* subdef = new mjCDef(*other.model->Default());
@@ -1845,10 +1841,6 @@ mjCFrame& mjCFrame::operator+=(const mjCBody& other) {
   other.model->prefix = "";
   other.model->suffix = "";
 
-  if (other.prefix.empty() && other.suffix.empty()) {
-    throw mjCError(this, "either prefix or suffix must be non-empty");
-  }
-
   mjCBody* subtree = new mjCBody(other, model);
   other.ForgetKeyframes();
   other.model->prefix = subtree->prefix;