Remove `EventEmitter

packages/dataverse/src/Box.ts

@@ -1,6 +1,5 @@
 import type {Prism} from './prism/Interface'
 import prism from './prism/prism'
-import EventEmitter from './utils/EventEmitter'
 
 /**
  * Common interface for Box types. Boxes wrap a single value.
@@ -39,7 +38,7 @@ export interface IBox<V> {
  */
 export default class Box<V> implements IBox<V> {
   private _publicPrism: Prism<V>
-  private _emitter = new EventEmitter()
+  private _changeListeners = new Set<(newVal: V) => void>()
 
   /**
    * @param _value - The initial value of the Box.
@@ -51,8 +50,8 @@ export default class Box<V> implements IBox<V> {
     protected _value: V,
   ) {
     const subscribe = (listener: (val: V) => void) => {
-      this._emitter.addEventListener('change', listener)
-      return () => this._emitter.removeEventListener('change', listener)
+      this._changeListeners.add(listener)
+      return () => this._changeListeners.delete(listener)
     }
 
     const getValue = () => this._value
@@ -69,7 +68,9 @@ export default class Box<V> implements IBox<V> {
   set(v: V) {
     if (v === this._value) return
     this._value = v
-    this._emitter.emit('change', v)
+    this._changeListeners.forEach((listener) => {
+      listener(v)
+    })
   }
 
   /**

packages/dataverse/src/utils/EventEmitter.ts

@@ -1,56 +0,0 @@
-import forEach from 'lodash-es/forEach'
-import without from 'lodash-es/without'
-import type {$FixMe} from '../types'
-
-type Listener = (v: $FixMe) => void
-
-/**
- * A simple barebones event emitter
- */
-export default class EventEmitter {
-  _listenersByType: {[eventName: string]: Array<Listener>}
-  constructor() {
-    this._listenersByType = {}
-  }
-
-  addEventListener(eventName: string, listener: Listener) {
-    const listeners =
-      this._listenersByType[eventName] ||
-      (this._listenersByType[eventName] = [])
-
-    listeners.push(listener)
-
-    return this
-  }
-
-  removeEventListener(eventName: string, listener: Listener) {
-    const listeners = this._listenersByType[eventName]
-    if (listeners) {
-      const newListeners = without(listeners, listener)
-      if (newListeners.length === 0) {
-        delete this._listenersByType[eventName]
-      } else {
-        this._listenersByType[eventName] = newListeners
-      }
-    }
-
-    return this
-  }
-
-  emit(eventName: string, payload: unknown) {
-    const listeners = this.getListenersFor(eventName)
-    if (listeners) {
-      forEach(listeners, (listener) => {
-        listener(payload)
-      })
-    }
-  }
-
-  getListenersFor(eventName: string) {
-    return this._listenersByType[eventName]
-  }
-
-  hasListenersFor(eventName: string) {
-    return this.getListenersFor(eventName) ? true : false
-  }
-}