feat: add triple term names

README.md

@@ -26,6 +26,14 @@ import type { DatasetCore } from '@rdfjs/types/dataset'
 import type { Stream } from '@rdfjs/types/stream'
 ``````
 
+## Helper Terms
+
+Note that some helper types exist that do not exist within the RDF/JS specifications. These include:
+
+```typescript
+import type { TripleTermName, QuadTermName } from '@rdfjs/types'
+```
+
 ## Contributing
 
 Everyone is invited to open issues and pull requests. When you create a PR, please add or update the `rdf-js-tests.ts` file to reflect your changes.

query/common.d.ts

@@ -4,10 +4,15 @@
 import { EventEmitter } from "events";
 import * as RDF from '../data-model';
 
+/**
+ * Helper union type for triple term names.
+ */
+export type TripleTermName = 'subject' | 'predicate' | 'object';
+
 /**
  * Helper union type for quad term names.
  */
-export type QuadTermName = 'subject' | 'predicate' | 'object' | 'graph';
+export type QuadTermName = TripleTermName | 'graph';
 
 // TODO: merge this with Stream upon the next major change
 /**