Add generic type

src/functions/accumulator.ts

@@ -17,7 +17,7 @@ function _accumulator<T>(
     const buffer: T[] = [];
     return new Transform({
         ...options,
-        transform(data: any, encoding, callback) {
+        transform(data: T, encoding, callback) {
             try {
                 accumulateBy(data, buffer, this);
                 callback();

src/functions/demux.ts

@@ -118,6 +118,7 @@ class Demux extends Writable {
         }
         return this;
     }
+
     public once(event: string, cb: any) {
         switch (eventsTarget[event]) {
             case EventSubscription.Self: