new features, adjust AttributeType.SetObsolete

at.go

@@ -1479,24 +1479,26 @@ func (r AttributeType) SetNoUserModification(x any) AttributeType {
 }
 
 /*
-SetObsolete assigns the input value to the underlying OBSOLETE clause within
-the receiver.
-
-Input types may be bool, or string representations of bool. When strings
-are used, case is not significant.
+SetObsolete sets the receiver's obsolescence state to true.
 
 Obsolescence cannot be unset.
 
 This is a fluent method.
 */
 func (r AttributeType) SetObsolete(x any) AttributeType {
 	if !r.IsZero() {
-		r.attributeType.setBoolean(`obs`, x)
+		r.attributeType.setObsolete()
 	}
 
 	return r
 }
 
+func (r *attributeType) setObsolete() {
+	if !r.Obsolete {
+		r.Obsolete = true
+	}
+}
+
 func (r *attributeType) setBoolean(t string, x any) {
 
 	var Bool bool

dc.go

@@ -445,6 +445,8 @@ func (r DITContentRules) Compliant() bool {
 /*
 StructuralClass returns the STRUCTURAL [ObjectClass] set within the
 receiver instance, or a zero instance if unset.
+
+This method is essentially the inverse of [ObjectClass.EnforcedBy].
 */
 func (r DITContentRule) StructuralClass() (soc ObjectClass) {
 	if !r.IsZero() {

dc_test.go

@@ -353,6 +353,7 @@ func TestDITContentRule_codecov(t *testing.T) {
 		t.Errorf("%s failed: expected success, got %v", t.Name(), err)
 		return
 	}
+	def.StructuralClass().EnforcedBy()
 	_ = def.macro()
 	def.setOID(`2.5.6.2`)
 

ds.go

@@ -96,6 +96,20 @@ func (r *dITStructureRule) replace(x DITStructureRule) {
 	r.data = x.dITStructureRule.data
 }
 
+/*
+NamedObjectClass returns the "namedObjectClass" of the receiver instance.
+
+The "namedObjectClass" describes the STRUCTURAL [ObjectClass] specified
+in the receiver's [NameForm] instance, and is described in [ITU-T Rec.
+X.501 clause 13.7.5].
+
+[ITU-T Rec. X.501 clause 13.7.5]: https://www.itu.int/rec/T-REC-X.501
+*/
+func (r DITStructureRule) NamedObjectClass() (noc ObjectClass) {
+	noc = r.Form().OC()
+	return
+}
+
 /*
 SetData assigns x to the receiver instance. This is a general-use method and has no
 specific intent beyond convenience. The contents may be subsequently accessed via the

ds_test.go

@@ -5,6 +5,13 @@ import (
 	"testing"
 )
 
+/*
+This example demonstrates an analysis of a distinguished name to determine
+whether it honors the receiver instance of [DITStructureRule].
+
+Note: this example assumes a legitimate schema variable is defined
+in place of the fictional "mySchema" var shown here for simplicity.
+*/
 func ExampleDITStructureRule_Govern() {
 	dn := `dc=example,dc=com` // flattened context (1 comma)
 
@@ -23,6 +30,9 @@ func ExampleDITStructureRule_Govern() {
 
 /*
 This example demonstrates the creation of a [DITStructureRule].
+
+Note: this example assumes a legitimate schema variable is defined
+in place of the fictional "mySchema" var shown here for simplicity.
 */
 func ExampleNewDITStructureRule() {
 	// First create a name form that requires an
@@ -53,6 +63,21 @@ func ExampleNewDITStructureRule() {
 	//     FORM fictionalPersonForm )
 }
 
+/*
+This example demonstrates the means of accessing the STRUCTURAL [ObjectClass]
+instance held by the [NameForm] instance assigned to the [DITStructureRule]
+instance.
+
+Note: this example assumes a legitimate schema variable is defined
+in place of the fictional "mySchema" var shown here for simplicity.
+*/
+func ExampleDITStructureRule_NamedObjectClass() {
+	ds := mySchema.DITStructureRules().Get(1) // Integer Identifier #1
+	noc := ds.NamedObjectClass()
+	fmt.Println(noc.OID())
+	// Output: uddiBusinessEntity
+}
+
 /*
 This example demonstrates a compliancy check of a [DITStructureRule]
 instance.

nf.go

@@ -189,6 +189,27 @@ func (r *nameForm) replace(x NameForm) {
 	r.data = x.nameForm.data
 }
 
+/*
+EnforcedBy returns an instance of [DITStructureRules] containing all
+[DITStructureRule] instances which enforce the receiver instance.  A
+return value with an integer length of zero (0) indicates that there
+are no [DITStructureRule] instances which bear the receiver instance
+through the 'FORM' clause at present.
+*/
+func (r NameForm) EnforcedBy() (dsr DITStructureRules) {
+	if !r.Schema().IsZero() {
+		dsr = NewDITStructureRules()
+		rules := r.Schema().DITStructureRules()
+		for i := 0; i < rules.Len(); i++ {
+			if ds := rules.Index(i); ds.Form().IsIdentifiedAs(r.OID()) {
+				dsr.Push(ds)
+			}
+		}
+	}
+
+	return
+}
+
 /*
 IsIdentifiedAs returns a Boolean value indicative of whether id matches
 either the numericOID or descriptor of the receiver instance.  Case is

nf_test.go

@@ -347,6 +347,7 @@ func TestNameForm_codecov(t *testing.T) {
 	_ = def.Name()
 	_ = def.Names()
 	_ = def.Extensions()
+	_ = def.EnforcedBy()
 	_ = def.Must()
 	_ = def.May()
 	_ = def.Schema()
@@ -395,6 +396,8 @@ func TestNameForm_codecov(t *testing.T) {
 		t.Errorf("%s failed: expected success, got %v", t.Name(), err)
 		return
 	}
+	def.EnforcedBy()
+
 	_ = def.macro()
 	def.setOID(`2.5.13.2`)
 

oc.go

@@ -146,6 +146,28 @@ func (r ObjectClass) macro() (m []string) {
 	return
 }
 
+/*
+EnforcedBy returns the [DITContentRule] instance which bears the same
+numeric OID held by the receiver instance, which must be a STRUCTURAL
+[ObjectClass].
+
+This method is essentially the inverse of [DITContentRule.StructuralClass].
+
+A schema can only contain one (1) such [DITContentRule] per STRUCTURAL
+[ObjectClass].
+
+If the return instance is zero, this means that either the receiver is
+not a STRUCTURAL [ObjectClass], or that no [DITContentRule] bearing the
+receiver's numeric OID is currently in force.
+*/
+func (r ObjectClass) EnforcedBy() (dcr DITContentRule) {
+	if !r.Schema().IsZero() && r.Kind() == StructuralKind {
+		dcr = r.Schema().DITContentRules().Get(r.NumericOID())
+	}
+
+	return
+}
+
 /*
 SetName assigns the provided names to the receiver instance.
 

oc_test.go

@@ -440,6 +440,7 @@ func TestObjectClass_codecov(t *testing.T) {
 	bmr.cast().Push(NewObjectClass().SetSchema(mySchema))
 	bmr.cast().Push(NewObjectClass().SetSchema(mySchema).SetNumericOID(`1.2.3.4.5`))
 	var bad ObjectClass
+	bad.EnforcedBy()
 	bmr.cast().Push(bad)
 
 	ObjectClasses(bmr.cast()).oIDsStringerPretty(0)
@@ -530,6 +531,7 @@ func TestObjectClass_codecov(t *testing.T) {
 	def.SetMust(rune(11))
 	def.SetMay(mySchema.AttributeTypes().Get(`cn`))
 	def.SetMay(rune(11))
+	def.EnforcedBy()
 	def.SetSuperClass(mySchema.ObjectClasses().Get(`top`))
 	def.SetSuperClass(rune(11))
 	def.SetSuperClass(ObjectClass{})