code: func (r *registry) initDecoratorPlugin(p *plugin.Plugin) {
  	constructorSymbol, err := p.Lookup(decoratorPluginFactory)
  	if err != nil {
  		panicWithLookupError(decoratorPluginFactory, err)
  	}
  	constructor, ok := constructorSymbol.(func() decoration.Decorator)
  	if !ok {
  		panicWithDefinitionError(decoratorPluginFactory)
  	}
  	decorator := constructor()
  	if decorator != nil {
  		r.decorators = append(r.decorators, constructor())
  	}
  }
docs: // initDecoratorPlugin constructs a decorator from the given plugin