DatasetWrapper API design improvements

Co-authored-by: Matthieu Bosquet <matthieubosquet@gmail.com>

Author: langsamu

src/DatasetWrapper.ts

@@ -4,34 +4,30 @@ import type { DataFactory, DatasetCore, Term } from "@rdfjs/types"
 type TermWrapperConstructor<T> = new (term: Term, dataset: DatasetCore, factory: DataFactory) => T
 
 export class DatasetWrapper extends DatasetCoreBase {
-    protected* subjectsOf<T>(termWrapper: TermWrapperConstructor<T>, predicate?: Term, object?: Term, graph?: Term): Iterable<T> {
+    protected subjectsOf<T>(predicate: Term, termWrapper: TermWrapperConstructor<T>): Iterable<T> {
+        return this.matchSubjectsOf(termWrapper, predicate)
+    }
+
+    protected* matchSubjectsOf<T>(termWrapper: TermWrapperConstructor<T>, predicate?: Term, object?: Term, graph?: Term): Iterable<T> {
         for (const q of this.match(undefined, predicate, object, graph)) {
             yield new termWrapper(q.subject, this, this.factory)
         }
     }
 
-    protected* objectsOf<T>(termWrapper: TermWrapperConstructor<T>, subject?: Term, predicate?: Term, graph?: Term): Iterable<T> {
-        for (const q of this.match(subject, predicate, undefined, graph)) {
-            yield new termWrapper(q.object, this, this.factory)
-        }
+    protected* objectsOf<T>(predicate: Term, termWrapper: TermWrapperConstructor<T>): Iterable<T> {
+        return this.matchObjectsOf(termWrapper, undefined, predicate)
     }
 
-    protected* objectsOfX<T>([s, p, g]: [Term?, Term?, Term?], termWrapper: TermWrapperConstructor<T>): Iterable<T> {
-        for (const q of this.match(s, p, undefined, g)) {
+    protected* matchObjectsOf<T>(termWrapper: TermWrapperConstructor<T>, subject?: Term, predicate?: Term, graph?: Term): Iterable<T> {
+        for (const q of this.match(subject, predicate, undefined, graph)) {
             yield new termWrapper(q.object, this, this.factory)
         }
     }
 
-    protected* subjectsOfX<T>([p, o, g]: [Term?, Term?, Term?], termWrapper: TermWrapperConstructor<T>): Iterable<T> {
-        for (const q of this.match(undefined, p, o, g)) {
-            yield new termWrapper(q.subject, this, this.factory)
-        }
-    }
-
-    protected instancesOf<T>(constructor: TermWrapperConstructor<T>, classTerm: Term): Iterable<T> {
+    protected instancesOf<T>(classTerm: Term, constructor: TermWrapperConstructor<T>): Iterable<T> {
         // TODO: Vocab
         const rdfType = this.factory.namedNode("http://www.w3.org/1999/02/22-rdf-syntax-ns#type")
 
-        return this.subjectsOf(constructor, rdfType, classTerm)
+        return this.matchSubjectsOf(constructor, rdfType, classTerm)
     }
 }

test/unit/model/MyDataset.ts

@@ -4,6 +4,6 @@ import { Vocabulary } from "../Vocabulary.js"
 
 export class MyDataset extends DatasetWrapper {
     public get parents(): Iterable<Parent> {
-        return this.subjectsOf(Parent, Vocabulary.hasChild)
+        return this.subjectsOf(Vocabulary.hasChild, Parent)
     }
 }