text: 
  class AbstractShaker {
    constructor(name) {
      if (!this.start) {
        throw new Error(`${name}: Missing start() implementation`)
      }
  
      if (!this.update) {
        throw new Error(`${name}: Missing update() implementation`)
      }
  
      if (!this.amplitude) {
        throw new Error(`${name}: Missing amplitude() implementation`)
      }
  
      if (!this.decay) {
        throw new Error(`${name}: Missing decay() implementation`)
      }
  
      if (!this.on) {
        throw new Error(`${name}: Missing on() implementation.`)
      }
    }
  }
  
  export default AbstractShaker
  