[467686] Correct name of SafeSource validation constraint
diff --git a/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/IterateExp.java b/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/IterateExp.java
index 745549c..440fc94 100644
--- a/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/IterateExp.java
+++ b/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/IterateExp.java
@@ -98,6 +98,6 @@
 	 * <!-- end-user-doc -->
 	 * @generated
 	 */
-	boolean validateSafeSourceCannotBeNull(DiagnosticChain diagnostics, Map<Object, Object> context);
+	boolean validateSafeSourceCanBeNull(DiagnosticChain diagnostics, Map<Object, Object> context);
 
 } // IterateExp
diff --git a/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/IteratorExp.java b/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/IteratorExp.java
index 7290603..5a503f9 100644
--- a/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/IteratorExp.java
+++ b/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/IteratorExp.java
@@ -145,5 +145,5 @@
 	 * <!-- end-user-doc -->
 	 * @generated
 	 */
-	boolean validateSafeSourceCannotBeNull(DiagnosticChain diagnostics, Map<Object, Object> context);
+	boolean validateSafeSourceCanBeNull(DiagnosticChain diagnostics, Map<Object, Object> context);
 } // IteratorExp
diff --git a/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/PivotPackage.java b/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/PivotPackage.java
index 08d2f73..9a35bcb 100644
--- a/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/PivotPackage.java
+++ b/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/PivotPackage.java
@@ -11290,13 +11290,13 @@
 	int ITERATE_EXP___VALIDATE_SAFE_ITERATOR_IS_REQUIRED__DIAGNOSTICCHAIN_MAP = LOOP_EXP_OPERATION_COUNT + 3;
 
 	/**
-	 * The operation id for the '<em>Validate Safe Source Cannot Be Null</em>' operation.
+	 * The operation id for the '<em>Validate Safe Source Can Be Null</em>' operation.
 	 * <!-- begin-user-doc -->
 	 * <!-- end-user-doc -->
 	 * @generated
 	 * @ordered
 	 */
-	int ITERATE_EXP___VALIDATE_SAFE_SOURCE_CANNOT_BE_NULL__DIAGNOSTICCHAIN_MAP = LOOP_EXP_OPERATION_COUNT + 4;
+	int ITERATE_EXP___VALIDATE_SAFE_SOURCE_CAN_BE_NULL__DIAGNOSTICCHAIN_MAP = LOOP_EXP_OPERATION_COUNT + 4;
 
 	/**
 	 * The operation id for the '<em>Validate Type Is Result Type</em>' operation.
@@ -12307,13 +12307,13 @@
 	int ITERATOR_EXP___VALIDATE_SAFE_ITERATOR_IS_REQUIRED__DIAGNOSTICCHAIN_MAP = LOOP_EXP_OPERATION_COUNT + 12;
 
 	/**
-	 * The operation id for the '<em>Validate Safe Source Cannot Be Null</em>' operation.
+	 * The operation id for the '<em>Validate Safe Source Can Be Null</em>' operation.
 	 * <!-- begin-user-doc -->
 	 * <!-- end-user-doc -->
 	 * @generated
 	 * @ordered
 	 */
-	int ITERATOR_EXP___VALIDATE_SAFE_SOURCE_CANNOT_BE_NULL__DIAGNOSTICCHAIN_MAP = LOOP_EXP_OPERATION_COUNT + 13;
+	int ITERATOR_EXP___VALIDATE_SAFE_SOURCE_CAN_BE_NULL__DIAGNOSTICCHAIN_MAP = LOOP_EXP_OPERATION_COUNT + 13;
 
 	/**
 	 * The operation id for the '<em>Validate Sorted By Element Type Is Source Element Type</em>' operation.
@@ -24030,14 +24030,14 @@
 	EOperation getIterateExp__ValidateSafeIteratorIsRequired__DiagnosticChain_Map();
 
 	/**
-	 * Returns the meta object for the '{@link org.eclipse.ocl.pivot.IterateExp#validateSafeSourceCannotBeNull(org.eclipse.emf.common.util.DiagnosticChain, java.util.Map) <em>Validate Safe Source Cannot Be Null</em>}' operation.
+	 * Returns the meta object for the '{@link org.eclipse.ocl.pivot.IterateExp#validateSafeSourceCanBeNull(org.eclipse.emf.common.util.DiagnosticChain, java.util.Map) <em>Validate Safe Source Can Be Null</em>}' operation.
 	 * <!-- begin-user-doc -->
 	 * <!-- end-user-doc -->
-	 * @return the meta object for the '<em>Validate Safe Source Cannot Be Null</em>' operation.
-	 * @see org.eclipse.ocl.pivot.IterateExp#validateSafeSourceCannotBeNull(org.eclipse.emf.common.util.DiagnosticChain, java.util.Map)
+	 * @return the meta object for the '<em>Validate Safe Source Can Be Null</em>' operation.
+	 * @see org.eclipse.ocl.pivot.IterateExp#validateSafeSourceCanBeNull(org.eclipse.emf.common.util.DiagnosticChain, java.util.Map)
 	 * @generated
 	 */
-	EOperation getIterateExp__ValidateSafeSourceCannotBeNull__DiagnosticChain_Map();
+	EOperation getIterateExp__ValidateSafeSourceCanBeNull__DiagnosticChain_Map();
 
 	/**
 	 * Returns the meta object for class '{@link org.eclipse.ocl.pivot.Iteration <em>Iteration</em>}'.
@@ -24242,14 +24242,14 @@
 	EOperation getIteratorExp__ValidateSafeIteratorIsRequired__DiagnosticChain_Map();
 
 	/**
-	 * Returns the meta object for the '{@link org.eclipse.ocl.pivot.IteratorExp#validateSafeSourceCannotBeNull(org.eclipse.emf.common.util.DiagnosticChain, java.util.Map) <em>Validate Safe Source Cannot Be Null</em>}' operation.
+	 * Returns the meta object for the '{@link org.eclipse.ocl.pivot.IteratorExp#validateSafeSourceCanBeNull(org.eclipse.emf.common.util.DiagnosticChain, java.util.Map) <em>Validate Safe Source Can Be Null</em>}' operation.
 	 * <!-- begin-user-doc -->
 	 * <!-- end-user-doc -->
-	 * @return the meta object for the '<em>Validate Safe Source Cannot Be Null</em>' operation.
-	 * @see org.eclipse.ocl.pivot.IteratorExp#validateSafeSourceCannotBeNull(org.eclipse.emf.common.util.DiagnosticChain, java.util.Map)
+	 * @return the meta object for the '<em>Validate Safe Source Can Be Null</em>' operation.
+	 * @see org.eclipse.ocl.pivot.IteratorExp#validateSafeSourceCanBeNull(org.eclipse.emf.common.util.DiagnosticChain, java.util.Map)
 	 * @generated
 	 */
-	EOperation getIteratorExp__ValidateSafeSourceCannotBeNull__DiagnosticChain_Map();
+	EOperation getIteratorExp__ValidateSafeSourceCanBeNull__DiagnosticChain_Map();
 
 	/**
 	 * Returns the meta object for class '{@link org.eclipse.ocl.pivot.LambdaType <em>Lambda Type</em>}'.
@@ -28962,12 +28962,12 @@
 		EOperation ITERATE_EXP___VALIDATE_SAFE_ITERATOR_IS_REQUIRED__DIAGNOSTICCHAIN_MAP = eINSTANCE.getIterateExp__ValidateSafeIteratorIsRequired__DiagnosticChain_Map();
 
 		/**
-		 * The meta object literal for the '<em><b>Validate Safe Source Cannot Be Null</b></em>' operation.
+		 * The meta object literal for the '<em><b>Validate Safe Source Can Be Null</b></em>' operation.
 		 * <!-- begin-user-doc -->
 		 * <!-- end-user-doc -->
 		 * @generated
 		 */
-		EOperation ITERATE_EXP___VALIDATE_SAFE_SOURCE_CANNOT_BE_NULL__DIAGNOSTICCHAIN_MAP = eINSTANCE.getIterateExp__ValidateSafeSourceCannotBeNull__DiagnosticChain_Map();
+		EOperation ITERATE_EXP___VALIDATE_SAFE_SOURCE_CAN_BE_NULL__DIAGNOSTICCHAIN_MAP = eINSTANCE.getIterateExp__ValidateSafeSourceCanBeNull__DiagnosticChain_Map();
 
 		/**
 		 * The meta object literal for the '{@link org.eclipse.ocl.pivot.internal.IterationImpl <em>Iteration</em>}' class.
@@ -29134,12 +29134,12 @@
 		EOperation ITERATOR_EXP___VALIDATE_SAFE_ITERATOR_IS_REQUIRED__DIAGNOSTICCHAIN_MAP = eINSTANCE.getIteratorExp__ValidateSafeIteratorIsRequired__DiagnosticChain_Map();
 
 		/**
-		 * The meta object literal for the '<em><b>Validate Safe Source Cannot Be Null</b></em>' operation.
+		 * The meta object literal for the '<em><b>Validate Safe Source Can Be Null</b></em>' operation.
 		 * <!-- begin-user-doc -->
 		 * <!-- end-user-doc -->
 		 * @generated
 		 */
-		EOperation ITERATOR_EXP___VALIDATE_SAFE_SOURCE_CANNOT_BE_NULL__DIAGNOSTICCHAIN_MAP = eINSTANCE.getIteratorExp__ValidateSafeSourceCannotBeNull__DiagnosticChain_Map();
+		EOperation ITERATOR_EXP___VALIDATE_SAFE_SOURCE_CAN_BE_NULL__DIAGNOSTICCHAIN_MAP = eINSTANCE.getIteratorExp__ValidateSafeSourceCanBeNull__DiagnosticChain_Map();
 
 		/**
 		 * The meta object literal for the '{@link org.eclipse.ocl.pivot.internal.LambdaTypeImpl <em>Lambda Type</em>}' class.
diff --git a/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/PivotTables.java b/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/PivotTables.java
index c65c199..6f95e15 100644
--- a/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/PivotTables.java
+++ b/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/PivotTables.java
@@ -210,7 +210,7 @@
     public static final @NonNull /*@NonInvalid*/ String STR_IterateExp_c_c_BodyTypeConformsToResultType = "IterateExp::BodyTypeConformsToResultType";
     public static final @NonNull /*@NonInvalid*/ String STR_IterateExp_c_c_OneInitializer = "IterateExp::OneInitializer";
     public static final @NonNull /*@NonInvalid*/ String STR_IterateExp_c_c_SafeIteratorIsRequired = "IterateExp::SafeIteratorIsRequired";
-    public static final @NonNull /*@NonInvalid*/ String STR_IterateExp_c_c_SafeSourceCannotBeNull = "IterateExp::SafeSourceCannotBeNull";
+    public static final @NonNull /*@NonInvalid*/ String STR_IterateExp_c_c_SafeSourceCanBeNull = "IterateExp::SafeSourceCanBeNull";
     public static final @NonNull /*@NonInvalid*/ String STR_IterateExp_c_c_TypeIsResultType = "IterateExp::TypeIsResultType";
     public static final @NonNull /*@NonInvalid*/ String STR_IterateExp_c_c_UnsafeSourceCanNotBeNull = "IterateExp::UnsafeSourceCanNotBeNull";
     public static final @NonNull /*@NonInvalid*/ String STR_IteratorExp_c_c_AnyBodyTypeIsBoolean = "IteratorExp::AnyBodyTypeIsBoolean";
@@ -225,7 +225,7 @@
     public static final @NonNull /*@NonInvalid*/ String STR_IteratorExp_c_c_CollectTypeIsUnordered = "IteratorExp::CollectTypeIsUnordered";
     public static final @NonNull /*@NonInvalid*/ String STR_IteratorExp_c_c_IteratorTypeIsSourceElementType = "IteratorExp::IteratorTypeIsSourceElementType";
     public static final @NonNull /*@NonInvalid*/ String STR_IteratorExp_c_c_SafeIteratorIsRequired = "IteratorExp::SafeIteratorIsRequired";
-    public static final @NonNull /*@NonInvalid*/ String STR_IteratorExp_c_c_SafeSourceCannotBeNull = "IteratorExp::SafeSourceCannotBeNull";
+    public static final @NonNull /*@NonInvalid*/ String STR_IteratorExp_c_c_SafeSourceCanBeNull = "IteratorExp::SafeSourceCanBeNull";
     public static final @NonNull /*@NonInvalid*/ String STR_IteratorExp_c_c_SortedByElementTypeIsSourceElementType = "IteratorExp::SortedByElementTypeIsSourceElementType";
     public static final @NonNull /*@NonInvalid*/ String STR_IteratorExp_c_c_SortedByIsOrderedIfSourceIsOrdered = "IteratorExp::SortedByIsOrderedIfSourceIsOrdered";
     public static final @NonNull /*@NonInvalid*/ String STR_IteratorExp_c_c_SortedByIteratorTypeIsComparable = "IteratorExp::SortedByIteratorTypeIsComparable";
diff --git a/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/internal/IterateExpImpl.java b/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/internal/IterateExpImpl.java
index 552883a..35eba39 100644
--- a/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/internal/IterateExpImpl.java
+++ b/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/internal/IterateExpImpl.java
@@ -456,8 +456,8 @@
 				return validateOneInitializer((DiagnosticChain)arguments.get(0), (Map<Object, Object>)arguments.get(1));
 			case PivotPackage.ITERATE_EXP___VALIDATE_SAFE_ITERATOR_IS_REQUIRED__DIAGNOSTICCHAIN_MAP:
 				return validateSafeIteratorIsRequired((DiagnosticChain)arguments.get(0), (Map<Object, Object>)arguments.get(1));
-			case PivotPackage.ITERATE_EXP___VALIDATE_SAFE_SOURCE_CANNOT_BE_NULL__DIAGNOSTICCHAIN_MAP:
-				return validateSafeSourceCannotBeNull((DiagnosticChain)arguments.get(0), (Map<Object, Object>)arguments.get(1));
+			case PivotPackage.ITERATE_EXP___VALIDATE_SAFE_SOURCE_CAN_BE_NULL__DIAGNOSTICCHAIN_MAP:
+				return validateSafeSourceCanBeNull((DiagnosticChain)arguments.get(0), (Map<Object, Object>)arguments.get(1));
 			case PivotPackage.ITERATE_EXP___VALIDATE_TYPE_IS_RESULT_TYPE__DIAGNOSTICCHAIN_MAP:
 				return validateTypeIsResultType((DiagnosticChain)arguments.get(0), (Map<Object, Object>)arguments.get(1));
 			case PivotPackage.ITERATE_EXP___VALIDATE_UNSAFE_SOURCE_CAN_NOT_BE_NULL__DIAGNOSTICCHAIN_MAP:
@@ -925,13 +925,12 @@
 	 * @generated
 	 */
 	@Override
-	public boolean validateSafeSourceCannotBeNull(final DiagnosticChain diagnostics, final Map<Object, Object> context)
+	public boolean validateSafeSourceCanBeNull(final DiagnosticChain diagnostics, final Map<Object, Object> context)
 	{
 		/**
 		 * 
-		 * inv validateSafeSourceCannotBeNull:
-		 *   let
-		 *     severity : Integer[1] = 'IterateExp::SafeSourceCannotBeNull'.getSeverity()
+		 * inv validateSafeSourceCanBeNull:
+		 *   let severity : Integer[1] = 'IterateExp::SafeSourceCanBeNull'.getSeverity()
 		 *   in
 		 *     if severity <= 0
 		 *     then true
@@ -939,12 +938,12 @@
 		 *       let status : Boolean[?] = isSafe implies
 		 *         not ownedSource?.type.oclAsType(CollectionType).isNullFree
 		 *       in
-		 *         'IterateExp::SafeSourceCannotBeNull'.logDiagnostic(self, diagnostics, context, severity, status, 0)
+		 *         'IterateExp::SafeSourceCanBeNull'.logDiagnostic(self, diagnostics, context, severity, status, 0)
 		 *     endif
 		 */
 		final @NonNull /*@NonInvalid*/ Evaluator evaluator = PivotUtilInternal.getEvaluator(this);
 		final @NonNull /*@NonInvalid*/ IdResolver idResolver = evaluator.getIdResolver();
-		final @NonNull /*@NonInvalid*/ IntegerValue severity_0 = CGStringGetSeverityOperation.INSTANCE.evaluate(evaluator, PivotTables.STR_IterateExp_c_c_SafeSourceCannotBeNull);
+		final @NonNull /*@NonInvalid*/ IntegerValue severity_0 = CGStringGetSeverityOperation.INSTANCE.evaluate(evaluator, PivotTables.STR_IterateExp_c_c_SafeSourceCanBeNull);
 		final /*@NonInvalid*/ boolean le = OclComparableLessThanEqualOperation.INSTANCE.evaluate(evaluator, severity_0, PivotTables.INT_0).booleanValue();
 		/*@NonInvalid*/ boolean symbol_1;
 		if (le) {
@@ -996,7 +995,7 @@
 		    catch (Exception e) {
 		        CAUGHT_status = ValueUtil.createInvalidValue(e);
 		    }
-		    final /*@NonInvalid*/ boolean logDiagnostic = CGStringLogDiagnosticOperation.INSTANCE.evaluate(evaluator, TypeId.BOOLEAN, PivotTables.STR_IterateExp_c_c_SafeSourceCannotBeNull, this, diagnostics, context, severity_0, CAUGHT_status, PivotTables.INT_0).booleanValue();
+		    final /*@NonInvalid*/ boolean logDiagnostic = CGStringLogDiagnosticOperation.INSTANCE.evaluate(evaluator, TypeId.BOOLEAN, PivotTables.STR_IterateExp_c_c_SafeSourceCanBeNull, this, diagnostics, context, severity_0, CAUGHT_status, PivotTables.INT_0).booleanValue();
 		    symbol_1 = logDiagnostic;
 		}
 		return Boolean.TRUE == symbol_1;
diff --git a/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/internal/IteratorExpImpl.java b/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/internal/IteratorExpImpl.java
index 5a2ea64..beb1beb 100644
--- a/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/internal/IteratorExpImpl.java
+++ b/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/internal/IteratorExpImpl.java
@@ -1638,13 +1638,12 @@
 	 * @generated
 	 */
 	@Override
-	public boolean validateSafeSourceCannotBeNull(final DiagnosticChain diagnostics, final Map<Object, Object> context)
+	public boolean validateSafeSourceCanBeNull(final DiagnosticChain diagnostics, final Map<Object, Object> context)
 	{
 		/**
 		 * 
-		 * inv validateSafeSourceCannotBeNull:
-		 *   let
-		 *     severity : Integer[1] = 'IteratorExp::SafeSourceCannotBeNull'.getSeverity()
+		 * inv validateSafeSourceCanBeNull:
+		 *   let severity : Integer[1] = 'IteratorExp::SafeSourceCanBeNull'.getSeverity()
 		 *   in
 		 *     if severity <= 0
 		 *     then true
@@ -1652,12 +1651,12 @@
 		 *       let status : Boolean[?] = isSafe implies
 		 *         not ownedSource?.type.oclAsType(CollectionType).isNullFree
 		 *       in
-		 *         'IteratorExp::SafeSourceCannotBeNull'.logDiagnostic(self, diagnostics, context, severity, status, 0)
+		 *         'IteratorExp::SafeSourceCanBeNull'.logDiagnostic(self, diagnostics, context, severity, status, 0)
 		 *     endif
 		 */
 		final @NonNull /*@NonInvalid*/ Evaluator evaluator = PivotUtilInternal.getEvaluator(this);
 		final @NonNull /*@NonInvalid*/ IdResolver idResolver = evaluator.getIdResolver();
-		final @NonNull /*@NonInvalid*/ IntegerValue severity_0 = CGStringGetSeverityOperation.INSTANCE.evaluate(evaluator, PivotTables.STR_IteratorExp_c_c_SafeSourceCannotBeNull);
+		final @NonNull /*@NonInvalid*/ IntegerValue severity_0 = CGStringGetSeverityOperation.INSTANCE.evaluate(evaluator, PivotTables.STR_IteratorExp_c_c_SafeSourceCanBeNull);
 		final /*@NonInvalid*/ boolean le = OclComparableLessThanEqualOperation.INSTANCE.evaluate(evaluator, severity_0, PivotTables.INT_0).booleanValue();
 		/*@NonInvalid*/ boolean symbol_1;
 		if (le) {
@@ -1709,7 +1708,7 @@
 		    catch (Exception e) {
 		        CAUGHT_status = ValueUtil.createInvalidValue(e);
 		    }
-		    final /*@NonInvalid*/ boolean logDiagnostic = CGStringLogDiagnosticOperation.INSTANCE.evaluate(evaluator, TypeId.BOOLEAN, PivotTables.STR_IteratorExp_c_c_SafeSourceCannotBeNull, this, diagnostics, context, severity_0, CAUGHT_status, PivotTables.INT_0).booleanValue();
+		    final /*@NonInvalid*/ boolean logDiagnostic = CGStringLogDiagnosticOperation.INSTANCE.evaluate(evaluator, TypeId.BOOLEAN, PivotTables.STR_IteratorExp_c_c_SafeSourceCanBeNull, this, diagnostics, context, severity_0, CAUGHT_status, PivotTables.INT_0).booleanValue();
 		    symbol_1 = logDiagnostic;
 		}
 		return Boolean.TRUE == symbol_1;
@@ -1764,8 +1763,8 @@
 				return validateIteratorTypeIsSourceElementType((DiagnosticChain)arguments.get(0), (Map<Object, Object>)arguments.get(1));
 			case PivotPackage.ITERATOR_EXP___VALIDATE_SAFE_ITERATOR_IS_REQUIRED__DIAGNOSTICCHAIN_MAP:
 				return validateSafeIteratorIsRequired((DiagnosticChain)arguments.get(0), (Map<Object, Object>)arguments.get(1));
-			case PivotPackage.ITERATOR_EXP___VALIDATE_SAFE_SOURCE_CANNOT_BE_NULL__DIAGNOSTICCHAIN_MAP:
-				return validateSafeSourceCannotBeNull((DiagnosticChain)arguments.get(0), (Map<Object, Object>)arguments.get(1));
+			case PivotPackage.ITERATOR_EXP___VALIDATE_SAFE_SOURCE_CAN_BE_NULL__DIAGNOSTICCHAIN_MAP:
+				return validateSafeSourceCanBeNull((DiagnosticChain)arguments.get(0), (Map<Object, Object>)arguments.get(1));
 			case PivotPackage.ITERATOR_EXP___VALIDATE_SORTED_BY_ELEMENT_TYPE_IS_SOURCE_ELEMENT_TYPE__DIAGNOSTICCHAIN_MAP:
 				return validateSortedByElementTypeIsSourceElementType((DiagnosticChain)arguments.get(0), (Map<Object, Object>)arguments.get(1));
 			case PivotPackage.ITERATOR_EXP___VALIDATE_SORTED_BY_IS_ORDERED_IF_SOURCE_IS_ORDERED__DIAGNOSTICCHAIN_MAP:
diff --git a/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/internal/PivotPackageImpl.java b/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/internal/PivotPackageImpl.java
index 2b13cbc..c5fb624 100644
--- a/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/internal/PivotPackageImpl.java
+++ b/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/internal/PivotPackageImpl.java
@@ -2302,7 +2302,7 @@
 	 * @generated
 	 */
 	@Override
-	public EOperation getIterateExp__ValidateSafeSourceCannotBeNull__DiagnosticChain_Map()
+	public EOperation getIterateExp__ValidateSafeSourceCanBeNull__DiagnosticChain_Map()
 	{
 		return iterateExpEClass.getEOperations().get(3);
 	}
@@ -2533,7 +2533,7 @@
 	 * @generated
 	 */
 	@Override
-	public EOperation getIteratorExp__ValidateSafeSourceCannotBeNull__DiagnosticChain_Map()
+	public EOperation getIteratorExp__ValidateSafeSourceCanBeNull__DiagnosticChain_Map()
 	{
 		return iteratorExpEClass.getEOperations().get(12);
 	}
@@ -6632,7 +6632,7 @@
 		createEOperation(iterateExpEClass, ITERATE_EXP___VALIDATE_BODY_TYPE_CONFORMS_TO_RESULT_TYPE__DIAGNOSTICCHAIN_MAP);
 		createEOperation(iterateExpEClass, ITERATE_EXP___VALIDATE_ONE_INITIALIZER__DIAGNOSTICCHAIN_MAP);
 		createEOperation(iterateExpEClass, ITERATE_EXP___VALIDATE_SAFE_ITERATOR_IS_REQUIRED__DIAGNOSTICCHAIN_MAP);
-		createEOperation(iterateExpEClass, ITERATE_EXP___VALIDATE_SAFE_SOURCE_CANNOT_BE_NULL__DIAGNOSTICCHAIN_MAP);
+		createEOperation(iterateExpEClass, ITERATE_EXP___VALIDATE_SAFE_SOURCE_CAN_BE_NULL__DIAGNOSTICCHAIN_MAP);
 		createEOperation(iterateExpEClass, ITERATE_EXP___VALIDATE_TYPE_IS_RESULT_TYPE__DIAGNOSTICCHAIN_MAP);
 		createEOperation(iterateExpEClass, ITERATE_EXP___VALIDATE_UNSAFE_SOURCE_CAN_NOT_BE_NULL__DIAGNOSTICCHAIN_MAP);
 
@@ -6653,7 +6653,7 @@
 		createEOperation(iteratorExpEClass, ITERATOR_EXP___VALIDATE_COLLECT_TYPE_IS_UNORDERED__DIAGNOSTICCHAIN_MAP);
 		createEOperation(iteratorExpEClass, ITERATOR_EXP___VALIDATE_ITERATOR_TYPE_IS_SOURCE_ELEMENT_TYPE__DIAGNOSTICCHAIN_MAP);
 		createEOperation(iteratorExpEClass, ITERATOR_EXP___VALIDATE_SAFE_ITERATOR_IS_REQUIRED__DIAGNOSTICCHAIN_MAP);
-		createEOperation(iteratorExpEClass, ITERATOR_EXP___VALIDATE_SAFE_SOURCE_CANNOT_BE_NULL__DIAGNOSTICCHAIN_MAP);
+		createEOperation(iteratorExpEClass, ITERATOR_EXP___VALIDATE_SAFE_SOURCE_CAN_BE_NULL__DIAGNOSTICCHAIN_MAP);
 		createEOperation(iteratorExpEClass, ITERATOR_EXP___VALIDATE_SORTED_BY_ELEMENT_TYPE_IS_SOURCE_ELEMENT_TYPE__DIAGNOSTICCHAIN_MAP);
 		createEOperation(iteratorExpEClass, ITERATOR_EXP___VALIDATE_SORTED_BY_IS_ORDERED_IF_SOURCE_IS_ORDERED__DIAGNOSTICCHAIN_MAP);
 		createEOperation(iteratorExpEClass, ITERATOR_EXP___VALIDATE_SORTED_BY_ITERATOR_TYPE_IS_COMPARABLE__DIAGNOSTICCHAIN_MAP);
@@ -7572,7 +7572,7 @@
 		g1.getETypeArguments().add(g2);
 		addEParameter(op, g1, "context", 0, 1, IS_UNIQUE, IS_ORDERED); //$NON-NLS-1$
 
-		op = initEOperation(getIterateExp__ValidateSafeSourceCannotBeNull__DiagnosticChain_Map(), ecorePackage.getEBoolean(), "validateSafeSourceCannotBeNull", 0, 1, IS_UNIQUE, IS_ORDERED); //$NON-NLS-1$
+		op = initEOperation(getIterateExp__ValidateSafeSourceCanBeNull__DiagnosticChain_Map(), ecorePackage.getEBoolean(), "validateSafeSourceCanBeNull", 0, 1, IS_UNIQUE, IS_ORDERED); //$NON-NLS-1$
 		addEParameter(op, ecorePackage.getEDiagnosticChain(), "diagnostics", 0, 1, IS_UNIQUE, IS_ORDERED); //$NON-NLS-1$
 		g1 = createEGenericType(ecorePackage.getEMap());
 		g2 = createEGenericType(ecorePackage.getEJavaObject());
@@ -7713,7 +7713,7 @@
 		g1.getETypeArguments().add(g2);
 		addEParameter(op, g1, "context", 0, 1, IS_UNIQUE, IS_ORDERED); //$NON-NLS-1$
 
-		op = initEOperation(getIteratorExp__ValidateSafeSourceCannotBeNull__DiagnosticChain_Map(), ecorePackage.getEBoolean(), "validateSafeSourceCannotBeNull", 0, 1, IS_UNIQUE, IS_ORDERED); //$NON-NLS-1$
+		op = initEOperation(getIteratorExp__ValidateSafeSourceCanBeNull__DiagnosticChain_Map(), ecorePackage.getEBoolean(), "validateSafeSourceCanBeNull", 0, 1, IS_UNIQUE, IS_ORDERED); //$NON-NLS-1$
 		addEParameter(op, ecorePackage.getEDiagnosticChain(), "diagnostics", 0, 1, IS_UNIQUE, IS_ORDERED); //$NON-NLS-1$
 		g1 = createEGenericType(ecorePackage.getEMap());
 		g2 = createEGenericType(ecorePackage.getEJavaObject());
diff --git a/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/util/PivotValidator.java b/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/util/PivotValidator.java
index 95e1f0d..e586445 100644
--- a/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/util/PivotValidator.java
+++ b/plugins/org.eclipse.ocl.pivot/emf-gen/org/eclipse/ocl/pivot/util/PivotValidator.java
@@ -328,12 +328,12 @@
 	public static final int ITERATE_EXP__VALIDATE_SAFE_ITERATOR_IS_REQUIRED = 19;
 
 	/**
-	 * The {@link org.eclipse.emf.common.util.Diagnostic#getCode() code} for constraint 'Validate Safe Source Cannot Be Null' of 'Iterate Exp'.
+	 * The {@link org.eclipse.emf.common.util.Diagnostic#getCode() code} for constraint 'Validate Safe Source Can Be Null' of 'Iterate Exp'.
 	 * <!-- begin-user-doc -->
 	 * <!-- end-user-doc -->
 	 * @generated
 	 */
-	public static final int ITERATE_EXP__VALIDATE_SAFE_SOURCE_CANNOT_BE_NULL = 20;
+	public static final int ITERATE_EXP__VALIDATE_SAFE_SOURCE_CAN_BE_NULL = 20;
 
 	/**
 	 * The {@link org.eclipse.emf.common.util.Diagnostic#getCode() code} for constraint 'Validate Type Is Result Type' of 'Iterate Exp'.
@@ -448,12 +448,12 @@
 	public static final int ITERATOR_EXP__VALIDATE_SAFE_ITERATOR_IS_REQUIRED = 34;
 
 	/**
-	 * The {@link org.eclipse.emf.common.util.Diagnostic#getCode() code} for constraint 'Validate Safe Source Cannot Be Null' of 'Iterator Exp'.
+	 * The {@link org.eclipse.emf.common.util.Diagnostic#getCode() code} for constraint 'Validate Safe Source Can Be Null' of 'Iterator Exp'.
 	 * <!-- begin-user-doc -->
 	 * <!-- end-user-doc -->
 	 * @generated
 	 */
-	public static final int ITERATOR_EXP__VALIDATE_SAFE_SOURCE_CANNOT_BE_NULL = 35;
+	public static final int ITERATOR_EXP__VALIDATE_SAFE_SOURCE_CAN_BE_NULL = 35;
 
 	/**
 	 * The {@link org.eclipse.emf.common.util.Diagnostic#getCode() code} for constraint 'Validate Sorted By Element Type Is Source Element Type' of 'Iterator Exp'.
@@ -2341,7 +2341,7 @@
 		if (result || diagnostics != null) result &= validateIterateExp_validateBodyTypeConformsToResultType(iterateExp, diagnostics, context);
 		if (result || diagnostics != null) result &= validateIterateExp_validateOneInitializer(iterateExp, diagnostics, context);
 		if (result || diagnostics != null) result &= validateIterateExp_validateSafeIteratorIsRequired(iterateExp, diagnostics, context);
-		if (result || diagnostics != null) result &= validateIterateExp_validateSafeSourceCannotBeNull(iterateExp, diagnostics, context);
+		if (result || diagnostics != null) result &= validateIterateExp_validateSafeSourceCanBeNull(iterateExp, diagnostics, context);
 		if (result || diagnostics != null) result &= validateIterateExp_validateTypeIsResultType(iterateExp, diagnostics, context);
 		if (result || diagnostics != null) result &= validateIterateExp_validateUnsafeSourceCanNotBeNull(iterateExp, diagnostics, context);
 		return result;
@@ -2370,14 +2370,14 @@
 	}
 
 	/**
-	 * Validates the validateSafeSourceCannotBeNull constraint of '<em>Iterate Exp</em>'.
+	 * Validates the validateSafeSourceCanBeNull constraint of '<em>Iterate Exp</em>'.
 	 * <!-- begin-user-doc -->
 	 * <!-- end-user-doc -->
 	 * @generated
 	 */
-	public boolean validateIterateExp_validateSafeSourceCannotBeNull(IterateExp iterateExp, DiagnosticChain diagnostics, Map<Object, Object> context)
+	public boolean validateIterateExp_validateSafeSourceCanBeNull(IterateExp iterateExp, DiagnosticChain diagnostics, Map<Object, Object> context)
 	{
-		return iterateExp.validateSafeSourceCannotBeNull(diagnostics, context);
+		return iterateExp.validateSafeSourceCanBeNull(diagnostics, context);
 	}
 
 	/**
@@ -2468,7 +2468,7 @@
 		if (result || diagnostics != null) result &= validateIteratorExp_validateCollectTypeIsUnordered(iteratorExp, diagnostics, context);
 		if (result || diagnostics != null) result &= validateIteratorExp_validateIteratorTypeIsSourceElementType(iteratorExp, diagnostics, context);
 		if (result || diagnostics != null) result &= validateIteratorExp_validateSafeIteratorIsRequired(iteratorExp, diagnostics, context);
-		if (result || diagnostics != null) result &= validateIteratorExp_validateSafeSourceCannotBeNull(iteratorExp, diagnostics, context);
+		if (result || diagnostics != null) result &= validateIteratorExp_validateSafeSourceCanBeNull(iteratorExp, diagnostics, context);
 		if (result || diagnostics != null) result &= validateIteratorExp_validateSortedByElementTypeIsSourceElementType(iteratorExp, diagnostics, context);
 		if (result || diagnostics != null) result &= validateIteratorExp_validateSortedByIsOrderedIfSourceIsOrdered(iteratorExp, diagnostics, context);
 		if (result || diagnostics != null) result &= validateIteratorExp_validateSortedByIteratorTypeIsComparable(iteratorExp, diagnostics, context);
@@ -2532,14 +2532,14 @@
 	}
 
 	/**
-	 * Validates the validateSafeSourceCannotBeNull constraint of '<em>Iterator Exp</em>'.
+	 * Validates the validateSafeSourceCanBeNull constraint of '<em>Iterator Exp</em>'.
 	 * <!-- begin-user-doc -->
 	 * <!-- end-user-doc -->
 	 * @generated
 	 */
-	public boolean validateIteratorExp_validateSafeSourceCannotBeNull(IteratorExp iteratorExp, DiagnosticChain diagnostics, Map<Object, Object> context)
+	public boolean validateIteratorExp_validateSafeSourceCanBeNull(IteratorExp iteratorExp, DiagnosticChain diagnostics, Map<Object, Object> context)
 	{
-		return iteratorExp.validateSafeSourceCannotBeNull(diagnostics, context);
+		return iteratorExp.validateSafeSourceCanBeNull(diagnostics, context);
 	}
 
 	/**
diff --git a/plugins/org.eclipse.ocl.pivot/model/Pivot.ecore b/plugins/org.eclipse.ocl.pivot/model/Pivot.ecore
index 0d83b7c..09f069a 100644
--- a/plugins/org.eclipse.ocl.pivot/model/Pivot.ecore
+++ b/plugins/org.eclipse.ocl.pivot/model/Pivot.ecore
@@ -638,7 +638,7 @@
         </eGenericType>
       </eParameters>
     </eOperations>
-    <eOperations name="validateSafeSourceCannotBeNull" eType="ecore:EDataType http://www.eclipse.org/emf/2002/Ecore#//EBoolean">
+    <eOperations name="validateSafeSourceCanBeNull" eType="ecore:EDataType http://www.eclipse.org/emf/2002/Ecore#//EBoolean">
       <eAnnotations source="http://www.eclipse.org/emf/2002/Ecore/OCL/Pivot">
         <details key="body" value="isSafe implies not ownedSource?.type.oclAsType(CollectionType).isNullFree&#xA;"/>
       </eAnnotations>
@@ -825,7 +825,7 @@
         </eGenericType>
       </eParameters>
     </eOperations>
-    <eOperations name="validateSafeSourceCannotBeNull" eType="ecore:EDataType http://www.eclipse.org/emf/2002/Ecore#//EBoolean">
+    <eOperations name="validateSafeSourceCanBeNull" eType="ecore:EDataType http://www.eclipse.org/emf/2002/Ecore#//EBoolean">
       <eAnnotations source="http://www.eclipse.org/emf/2002/Ecore/OCL/Pivot">
         <details key="body" value="isSafe implies not ownedSource?.type.oclAsType(CollectionType).isNullFree&#xA;"/>
       </eAnnotations>
diff --git a/plugins/org.eclipse.ocl.pivot/model/Pivot.ocl b/plugins/org.eclipse.ocl.pivot/model/Pivot.ocl
index 31e3f04..780a97e 100644
--- a/plugins/org.eclipse.ocl.pivot/model/Pivot.ocl
+++ b/plugins/org.eclipse.ocl.pivot/model/Pivot.ocl
@@ -271,7 +271,7 @@
 /** The type of each iterator variable must be the type of the elements of the source collection. */
 inv IteratorTypeIsSourceElementType: self.ownedIterators->forAll(p | ownedSource?.type.oclAsType(CollectionType).elementType.conformsTo(p?.type))
 /** Safe navigation is not necessary when the source collection is null-free. */
-inv SafeSourceCannotBeNull: isSafe implies not ownedSource?.type.oclAsType(CollectionType).isNullFree
+inv SafeSourceCanBeNull: isSafe implies not ownedSource?.type.oclAsType(CollectionType).isNullFree
 /** Safe navigation is not necessary when an iterator can be null. */
 inv SafeIteratorIsRequired: isSafe implies ownedIterators?->forAll(isRequired)
 /** Safe navigation is necessary when an iterator cannot be null and the source collection is not null-free. */
@@ -279,7 +279,7 @@
 
 context IterateExp
 /** Safe navigation is not necessary when the source collection is null-free. */
-inv SafeSourceCannotBeNull: isSafe implies not ownedSource?.type.oclAsType(CollectionType).isNullFree
+inv SafeSourceCanBeNull: isSafe implies not ownedSource?.type.oclAsType(CollectionType).isNullFree
 /** Safe navigation is not necessary when an iterator can be null. */
 inv SafeIteratorIsRequired: isSafe implies ownedIterators?->forAll(isRequired)
 /** Safe navigation is necessary when an iterator cannot be null and the source collection is not null-free. */
diff --git a/plugins/org.eclipse.ocl.pivot/src/org/eclipse/ocl/pivot/options/PivotValidationOptions.java b/plugins/org.eclipse.ocl.pivot/src/org/eclipse/ocl/pivot/options/PivotValidationOptions.java
index 06ca24e..f2b56ba 100644
--- a/plugins/org.eclipse.ocl.pivot/src/org/eclipse/ocl/pivot/options/PivotValidationOptions.java
+++ b/plugins/org.eclipse.ocl.pivot/src/org/eclipse/ocl/pivot/options/PivotValidationOptions.java
@@ -38,10 +38,10 @@
     
     static {
     	safeValidationName2severityOption.put(PivotTables.STR_IterateExp_c_c_SafeIteratorIsRequired, PivotValidationOptions.RedundantSafeNavigation);
-    	safeValidationName2severityOption.put(PivotTables.STR_IterateExp_c_c_SafeSourceCannotBeNull, PivotValidationOptions.RedundantSafeNavigation);
+    	safeValidationName2severityOption.put(PivotTables.STR_IterateExp_c_c_SafeSourceCanBeNull, PivotValidationOptions.RedundantSafeNavigation);
     	safeValidationName2severityOption.put(PivotTables.STR_IterateExp_c_c_UnsafeSourceCanNotBeNull, PivotValidationOptions.MissingSafeNavigation);
     	safeValidationName2severityOption.put(PivotTables.STR_IteratorExp_c_c_SafeIteratorIsRequired, PivotValidationOptions.RedundantSafeNavigation);
-    	safeValidationName2severityOption.put(PivotTables.STR_IteratorExp_c_c_SafeSourceCannotBeNull, PivotValidationOptions.RedundantSafeNavigation);
+    	safeValidationName2severityOption.put(PivotTables.STR_IteratorExp_c_c_SafeSourceCanBeNull, PivotValidationOptions.RedundantSafeNavigation);
     	safeValidationName2severityOption.put(PivotTables.STR_IteratorExp_c_c_UnsafeSourceCanNotBeNull, PivotValidationOptions.MissingSafeNavigation);
     	safeValidationName2severityOption.put(PivotTables.STR_OperationCallExp_c_c_SafeSourceCanBeNull, PivotValidationOptions.RedundantSafeNavigation);
 //    	safeValidationName2severityOption.put(PivotTables.STR_OperationCallExp_c_c_UnsafeSourceCanNotBeNull, PivotValidationOptions.MissingSafeNavigation);