Neomerx\JsonApi\Contracts\Schema\ResourceObjectInterface::isInArray PHP Method

    public function isInArray();

 /**
  * @inheritdoc
  */
 public function addToData(ResourceObjectInterface $resource)
 {
     // check if 'not-arrayed' data were added you cannot add to 'non-array' data section anymore
     assert('$this->isDataArrayed === null || $this->isDataArrayed === true');
     $this->isDataArrayed !== null ?: ($this->isDataArrayed = $resource->isInArray());
     // check all resources have the same isInArray flag
     assert('$this->isDataArrayed === $resource->isInArray()');
     $idx = $resource->getId();
     $type = $resource->getType();
     assert('isset($this->bufferForData[$type][$idx]) === false');
     $this->bufferForData[$type][$idx] = $this->presenter->convertDataResourceToArray($resource, true);
     $this->hasBeenMetAlready[$type][$idx] = true;
     // check if resource has already been added to included
     // (for example as related resource of one of the previous main resources)
     if (isset($this->includedResources[$type][$idx]) === true) {
         $includedIndex = $this->includedResources[$type][$idx];
         // remove duplicate from 'included' (leave only in main resources)
         unset($this->included[$includedIndex]);
     }
 }