--- a/src/core/attribute-test.cc	Sun Mar 09 21:07:35 2008 +0100
+++ b/src/core/attribute-test.cc	Sun Mar 09 21:28:27 2008 +0100
@@ -245,11 +245,11 @@
   CHECK_GET_STR (p, "TestBoolName", "false");
   CHECK_GET_PARAM (p, "TestBoolName", Boolean, false);
 
-  NS_TEST_ASSERT (p->SetAttribute("TestBoolName", String ("true")));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe("TestBoolName", String ("true")));
   CHECK_GET_STR (p, "TestBoolName", "true");
   CHECK_GET_PARAM (p, "TestBoolName", Boolean, true);
 
-  NS_TEST_ASSERT (p->SetAttribute("TestBoolName", Boolean (false)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe("TestBoolName", Boolean (false)));
   CHECK_GET_STR (p, "TestBoolName", "false");
   CHECK_GET_PARAM (p, "TestBoolName", Boolean, false);
 
@@ -261,11 +261,11 @@
   CHECK_GET_STR (p, "TestBoolName", "true");
   CHECK_GET_PARAM (p, "TestBoolName", Boolean, true);
 
-  NS_TEST_ASSERT (p->SetAttribute("TestBoolA", String ("false")));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe("TestBoolA", String ("false")));
   CHECK_GET_STR (p, "TestBoolA", "false");
   CHECK_GET_PARAM (p, "TestBoolA", Boolean, false);
 
-  NS_TEST_ASSERT (p->SetAttribute("TestBoolA", String ("true")));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe("TestBoolA", String ("true")));
   CHECK_GET_STR (p, "TestBoolA", "true");
   CHECK_GET_PARAM (p, "TestBoolA", Boolean, true);
 
@@ -273,7 +273,7 @@
   Ptr<Derived> derived = p->GetAttribute ("TestPtr");
   NS_TEST_ASSERT (derived == 0);
   derived = Create<Derived> ();
-  NS_TEST_ASSERT (p->SetAttribute("TestPtr", derived));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe("TestPtr", derived));
   Ptr<Derived> stored = p->GetAttribute ("TestPtr");
   NS_TEST_ASSERT (stored == derived);
   Ptr<Object> storedBase = p->GetAttribute ("TestPtr");
@@ -290,93 +290,93 @@
   CHECK_GET_STR (p, "TestInt16", "-2");
   CHECK_GET_PARAM (p, "TestInt16", Integer, -2);
 
-  NS_TEST_ASSERT (p->SetAttribute("TestInt16", String ("-5")));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe("TestInt16", String ("-5")));
   CHECK_GET_STR (p, "TestInt16", "-5");
   CHECK_GET_PARAM (p, "TestInt16", Integer, -5);
 
-  NS_TEST_ASSERT (p->SetAttribute("TestInt16", Integer (+2)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe("TestInt16", Integer (+2)));
   CHECK_GET_STR (p, "TestInt16", "2");
   CHECK_GET_PARAM (p, "TestInt16", Integer, +2);
 
-  NS_TEST_ASSERT (p->SetAttribute("TestInt16", Integer (-32768)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe("TestInt16", Integer (-32768)));
   CHECK_GET_STR (p, "TestInt16", "-32768");
   CHECK_GET_PARAM (p, "TestInt16", Integer, -32768);
 
-  NS_TEST_ASSERT (!p->SetAttribute("TestInt16", Integer (-32769)));
+  NS_TEST_ASSERT (!p->SetAttributeFailSafe("TestInt16", Integer (-32769)));
   CHECK_GET_STR (p, "TestInt16", "-32768");
   CHECK_GET_PARAM (p, "TestInt16", Integer, -32768);
 
-  NS_TEST_ASSERT (p->SetAttribute("TestInt16", Integer (32767)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe("TestInt16", Integer (32767)));
   CHECK_GET_STR (p, "TestInt16", "32767");
   CHECK_GET_PARAM (p, "TestInt16", Integer, 32767);
 
-  NS_TEST_ASSERT (!p->SetAttribute("TestInt16", Integer (32768)));
+  NS_TEST_ASSERT (!p->SetAttributeFailSafe("TestInt16", Integer (32768)));
   CHECK_GET_STR (p, "TestInt16", "32767");
   CHECK_GET_PARAM (p, "TestInt16", Integer, 32767);
 
-  NS_TEST_ASSERT (p->SetAttribute("TestInt16WithBounds", Integer (10)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe("TestInt16WithBounds", Integer (10)));
   CHECK_GET_STR (p, "TestInt16WithBounds", "10");
   CHECK_GET_PARAM (p, "TestInt16WithBounds", Integer, 10);
-  NS_TEST_ASSERT (!p->SetAttribute("TestInt16WithBounds", Integer (11)));
+  NS_TEST_ASSERT (!p->SetAttributeFailSafe("TestInt16WithBounds", Integer (11)));
   CHECK_GET_STR (p, "TestInt16WithBounds", "10");
   CHECK_GET_PARAM (p, "TestInt16WithBounds", Integer, 10);
 
-  NS_TEST_ASSERT (p->SetAttribute("TestInt16WithBounds", Integer (-5)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe("TestInt16WithBounds", Integer (-5)));
   CHECK_GET_STR (p, "TestInt16WithBounds", "-5");
   CHECK_GET_PARAM (p, "TestInt16WithBounds", Integer, -5);
-  NS_TEST_ASSERT (!p->SetAttribute("TestInt16WithBounds", Integer (-6)));
+  NS_TEST_ASSERT (!p->SetAttributeFailSafe("TestInt16WithBounds", Integer (-6)));
   CHECK_GET_STR (p, "TestInt16WithBounds", "-5");
   CHECK_GET_PARAM (p, "TestInt16WithBounds", Integer, -5);
 
   CHECK_GET_STR (p, "TestInt16SetGet", "6");
   CHECK_GET_PARAM (p, "TestInt16SetGet", Integer, 6);
-  NS_TEST_ASSERT (p->SetAttribute("TestInt16SetGet", Integer (0)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe("TestInt16SetGet", Integer (0)));
   CHECK_GET_STR (p, "TestInt16SetGet", "0");
   CHECK_GET_PARAM (p, "TestInt16SetGet", Integer, 0);
 
   CHECK_GET_STR (p, "TestUint8", "1");
   CHECK_GET_PARAM (p, "TestUint8", Uinteger, 1);
-  NS_TEST_ASSERT (p->SetAttribute("TestUint8", Uinteger (0)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe("TestUint8", Uinteger (0)));
   CHECK_GET_STR (p, "TestUint8", "0");
   CHECK_GET_PARAM (p, "TestUint8", Uinteger, 0);
-  NS_TEST_ASSERT (p->SetAttribute("TestUint8", Uinteger (255)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe("TestUint8", Uinteger (255)));
   CHECK_GET_STR (p, "TestUint8", "255");
   CHECK_GET_PARAM (p, "TestUint8", Uinteger, 255);
-  NS_TEST_ASSERT (p->SetAttribute("TestUint8", String ("255")));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe("TestUint8", String ("255")));
   CHECK_GET_STR (p, "TestUint8", "255");
   CHECK_GET_PARAM (p, "TestUint8", Uinteger, 255);
-  NS_TEST_ASSERT (!p->SetAttribute("TestUint8", String ("256")));
+  NS_TEST_ASSERT (!p->SetAttributeFailSafe("TestUint8", String ("256")));
   CHECK_GET_STR (p, "TestUint8", "255");
   CHECK_GET_PARAM (p, "TestUint8", Uinteger, 255);
-  NS_TEST_ASSERT (!p->SetAttribute("TestUint8", String ("-1")));
+  NS_TEST_ASSERT (!p->SetAttributeFailSafe("TestUint8", String ("-1")));
   CHECK_GET_STR (p, "TestUint8", "255");
   CHECK_GET_PARAM (p, "TestUint8", Uinteger, 255);
-  NS_TEST_ASSERT (!p->SetAttribute("TestUint8", Uinteger ((uint64_t)-1)));
+  NS_TEST_ASSERT (!p->SetAttributeFailSafe("TestUint8", Uinteger ((uint64_t)-1)));
   CHECK_GET_STR (p, "TestUint8", "255");
   CHECK_GET_PARAM (p, "TestUint8", Uinteger, 255);
 
   CHECK_GET_STR (p, "TestFloat", "-1.1");
-  NS_TEST_ASSERT (p->SetAttribute("TestFloat", Double ((float)+2.3)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe("TestFloat", Double ((float)+2.3)));
   CHECK_GET_PARAM (p, "TestFloat", Double, (float)+2.3);
 
   CHECK_GET_STR (p, "TestEnum", "TestA");
   CHECK_GET_PARAM (p, "TestEnum", Enum, AttributeObjectTest::TEST_A);
-  NS_TEST_ASSERT (p->SetAttribute("TestEnum", Enum (AttributeObjectTest::TEST_C)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe("TestEnum", Enum (AttributeObjectTest::TEST_C)));
   CHECK_GET_STR (p, "TestEnum", "TestC");
   CHECK_GET_PARAM (p, "TestEnum", Enum, AttributeObjectTest::TEST_C);
-  NS_TEST_ASSERT (p->SetAttribute("TestEnum", String ("TestB")));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe("TestEnum", String ("TestB")));
   CHECK_GET_STR (p, "TestEnum", "TestB");
   CHECK_GET_PARAM (p, "TestEnum", Enum, AttributeObjectTest::TEST_B);
-  NS_TEST_ASSERT (!p->SetAttribute("TestEnum", String ("TestD")));
+  NS_TEST_ASSERT (!p->SetAttributeFailSafe("TestEnum", String ("TestD")));
   CHECK_GET_STR (p, "TestEnum", "TestB");
   CHECK_GET_PARAM (p, "TestEnum", Enum, AttributeObjectTest::TEST_B);
-  NS_TEST_ASSERT (!p->SetAttribute("TestEnum", Enum (5)));
+  NS_TEST_ASSERT (!p->SetAttributeFailSafe("TestEnum", Enum (5)));
   CHECK_GET_STR (p, "TestEnum", "TestB");
   CHECK_GET_PARAM (p, "TestEnum", Enum, AttributeObjectTest::TEST_B);
 
   RandomVariable ran = p->GetAttribute ("TestRandom");
-  NS_TEST_ASSERT (p->SetAttribute("TestRandom", UniformVariable (0.0, 1.0)));
-  NS_TEST_ASSERT (p->SetAttribute("TestRandom", ConstantVariable (10.0)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe("TestRandom", UniformVariable (0.0, 1.0)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe("TestRandom", ConstantVariable (10.0)));
 
   {
     ObjectVector vector = p->GetAttribute ("TestVector1");
@@ -420,31 +420,31 @@
 
   Integer i = p->GetAttribute ("IntegerTraceSource1");
   NS_TEST_ASSERT_EQUAL (i.Get (), -2);
-  NS_TEST_ASSERT (p->SetAttribute ("IntegerTraceSource1", Integer (+5)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe ("IntegerTraceSource1", Integer (+5)));
   i = p->GetAttribute ("IntegerTraceSource1");
   NS_TEST_ASSERT_EQUAL (i.Get (), +5);
-  NS_TEST_ASSERT (p->SetAttribute ("IntegerTraceSource1", Integer (127)));
-  NS_TEST_ASSERT (!p->SetAttribute ("IntegerTraceSource1", Integer (128)));
-  NS_TEST_ASSERT (p->SetAttribute ("IntegerTraceSource1", Integer (-128)));
-  NS_TEST_ASSERT (!p->SetAttribute ("IntegerTraceSource1", Integer (-129)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe ("IntegerTraceSource1", Integer (127)));
+  NS_TEST_ASSERT (!p->SetAttributeFailSafe ("IntegerTraceSource1", Integer (128)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe ("IntegerTraceSource1", Integer (-128)));
+  NS_TEST_ASSERT (!p->SetAttributeFailSafe ("IntegerTraceSource1", Integer (-129)));
 
   i = p->GetAttribute ("IntegerTraceSource2");
   NS_TEST_ASSERT_EQUAL (i.Get (), -2);
-  NS_TEST_ASSERT (p->SetAttribute ("IntegerTraceSource2", Integer (+5)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe ("IntegerTraceSource2", Integer (+5)));
   i = p->GetAttribute ("IntegerTraceSource2");
   NS_TEST_ASSERT_EQUAL (i.Get (), +5);
-  NS_TEST_ASSERT (p->SetAttribute ("IntegerTraceSource2", Integer (127)));
-  NS_TEST_ASSERT (!p->SetAttribute ("IntegerTraceSource2", Integer (128)));
-  NS_TEST_ASSERT (p->SetAttribute ("IntegerTraceSource2", Integer (-128)));
-  NS_TEST_ASSERT (!p->SetAttribute ("IntegerTraceSource2", Integer (-129)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe ("IntegerTraceSource2", Integer (127)));
+  NS_TEST_ASSERT (!p->SetAttributeFailSafe ("IntegerTraceSource2", Integer (128)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe ("IntegerTraceSource2", Integer (-128)));
+  NS_TEST_ASSERT (!p->SetAttributeFailSafe ("IntegerTraceSource2", Integer (-129)));
 
   m_got1 = -2;
-  NS_TEST_ASSERT (p->SetAttribute ("IntegerTraceSource1", Integer (-1)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe ("IntegerTraceSource1", Integer (-1)));
   NS_TEST_ASSERT (p->TraceSourceConnect ("Source1", MakeCallback (&AttributeTest::NotifySource1, this)));
-  NS_TEST_ASSERT (p->SetAttribute ("IntegerTraceSource1", Integer (0)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe ("IntegerTraceSource1", Integer (0)));
   NS_TEST_ASSERT_EQUAL (m_got1, 0);
   NS_TEST_ASSERT (p->TraceSourceDisconnect ("Source1", MakeCallback (&AttributeTest::NotifySource1, this)));
-  NS_TEST_ASSERT (p->SetAttribute ("IntegerTraceSource1", Integer (1)));
+  NS_TEST_ASSERT (p->SetAttributeFailSafe ("IntegerTraceSource1", Integer (1)));
   NS_TEST_ASSERT_EQUAL (m_got1, 0);
 
   m_got2 = 4.3;

--- a/src/core/object.cc	Sun Mar 09 21:07:35 2008 +0100
+++ b/src/core/object.cc	Sun Mar 09 21:28:27 2008 +0100
@@ -1075,12 +1075,29 @@
   ok = spec->Set (this, value);
   return ok;
 }
-bool
+void
 Object::SetAttribute (std::string name, Attribute value)
 {
   struct TypeId::AttributeInfo info;
   if (!m_tid.LookupAttributeByName (name, &info))
     {
+      NS_FATAL_ERROR ("Attribute name="<<name<<" does not exist for this object: tid="<<m_tid.GetName ());
+    }
+  if (!(info.flags & TypeId::ATTR_SET))
+    {
+      NS_FATAL_ERROR ("Attribute name="<<name<<" is not settable for this object: tid="<<m_tid.GetName ());
+    }
+  if (!DoSet (info.accessor, info.initialValue, info.checker, value))
+    {
+      NS_FATAL_ERROR ("Attribute name="<<name<<" could not be set for this object: tid="<<m_tid.GetName ());
+    }
+}
+bool 
+Object::SetAttributeFailSafe (std::string name, Attribute value)
+{
+  struct TypeId::AttributeInfo info;
+  if (!m_tid.LookupAttributeByName (name, &info))
+    {
       return false;
     }
   if (!(info.flags & TypeId::ATTR_SET))

--- a/src/core/object.h	Sun Mar 09 21:07:35 2008 +0100
+++ b/src/core/object.h	Sun Mar 09 21:28:27 2008 +0100
@@ -384,9 +384,11 @@
    * \param name the name of the attribute to set
    * \param value the name of the attribute to set
    *
-   * Set a single attribute.
+   * Set a single attribute. This cannot fail: if the input is invalid,
+   * it will crash immediately.
    */
-  bool SetAttribute (std::string name, Attribute value);
+  void SetAttribute (std::string name, Attribute value);
+  bool SetAttributeFailSafe (std::string name, Attribute value);
   /**
    * \param name the name of the attribute to read
    * \param value a reference to the string where the value of the 

--- a/src/node/drop-tail-queue.cc	Sun Mar 09 21:07:35 2008 +0100
+++ b/src/node/drop-tail-queue.cc	Sun Mar 09 21:28:27 2008 +0100
@@ -133,7 +133,7 @@
   bool result = true;
 
   Ptr<DropTailQueue> queue = CreateObject<DropTailQueue> ();
-  NS_TEST_ASSERT (queue->SetAttribute ("MaxPackets", Uinteger (3)));
+  NS_TEST_ASSERT (queue->SetAttributeFailSafe ("MaxPackets", Uinteger (3)));
   
   Ptr<Packet> p1, p2, p3, p4;
   p1 = Create<Packet> ();