Make ESLint require backticks.

.eslintrc.js

@@ -8,6 +8,7 @@ module.exports = {
     ecmaVersion: 2017
   },
   rules: {
+    quotes: ["error", "backtick"],
     "no-undef": "error",
     "no-unused-vars": "warn"
   }

lib/index.js

@@ -368,7 +368,7 @@ Channel.from = (values, mapfn, thisArg) => {
         }
       } catch (exception) {
         // Node.js stream.readable
-        values.on("readable", async () => {
+        values.on(`readable`, async () => {
           while (true) {
             const data = values.read();
 
@@ -380,7 +380,7 @@ Channel.from = (values, mapfn, thisArg) => {
           }
         });
 
-        values.once("end", channel.close);
+        values.once(`end`, channel.close);
       }
     }
   })();