--- a/src/layout/rdf_value.test.ts	Sun Mar 20 00:54:19 2022 -0700
+++ b/src/layout/rdf_value.test.ts	Sun Mar 20 01:17:35 2022 -0700
@@ -3,6 +3,7 @@
 import { EX } from "./namespaces";
 import { uniqueSortedTerms } from "./rdf_value";
 const { namedNode, literal } = DataFactory;
+
 describe("Immutable.Set", () => {
   it("contains", () => {
     const s = Immutable.Set([EX("e1")]);
@@ -11,6 +12,14 @@
   });
 });
 
+describe("Immutable.Map", () => {
+  it("gets", () => {
+    let m: Immutable.Map<NamedNode, number> = Immutable.Map();
+    m = m.set(EX("e1"), 5);
+    expect(m.get(EX("e1"))).toEqual(5);
+  });
+});
+
 const uri1 = namedNode("http://example.com/1");
 const uri2 = namedNode("http://example.com/2");
 const lit1 = literal("lit1");