TEmitter¶

Overview¶

Event & listener abstraction for a single "event" type. Unified interface for usage across the concrete implementations: - Emitter: PhET-iO instrumented Emitter - TinyEmitter: Lightweight version without phet-io for when performance/memory are critical

@author Sam Reid (PhET Interactive Simulations)

Type TEmitter¶

import type { TEmitter } from 'scenerystack/axon';

TReadOnlyEmitter<T> & { emit: ( ...args: T ) => void; dispose: () => void }

Type TEmitterListener¶

import type { TEmitterListener } from 'scenerystack/axon';

( ...args: T ) => void

Type TEmitterParameter¶

undefined and never are not allowed as parameters to Emitter

import type { TEmitterParameter } from 'scenerystack/axon';

Exclude<IntentionalAny, undefined | never>

Type TReadOnlyEmitter¶

A "read only" version of an emitter. You can listen to it, but cannot control it

import type { TReadOnlyEmitter } from 'scenerystack/axon';

• addListener: ( listener: TEmitterListener<T> ) => void
• hasListener: ( listener: TEmitterListener<T> ) => boolean
• removeListener: ( listener: TEmitterListener<T> ) => void
• removeAllListeners: () => void

Source Code¶

See the source for TEmitter.ts in the axon repository.