class {
    onCreate() {
        this.state = {
            listening: false
        }
    }

    toggle() {
        this.state.listening = !this.state.listening;
    }

    handleMove(e) {
      ...
    }
}

<button on-click('toggle')>
  <if(state.listening)>
    <!-- Only logs mouse moves if we are in the listening state -->
    <subscribe to=window on-mousemove('handleMove')/>
    Stop Listening
  </if>
  <else>
    Listen
  </else>
</button>

<subscribe
  to=EventEmitter|EventTarget
  on-*(string, ...args)
  once-*(string, ...args)/>