original_string: public function pop()
      {
          $this->internalDataListUpdate();
          if (isset($this->internalDataListData[0])) {
              $this->internalDataListUpdateValueIfNeeded($this->internalDataListData, sizeof($this->internalDataListData) - 1);
              return array_pop($this->internalDataListData);
          }
          return null;
      }
code: public function pop()
      {
          $this->internalDataListUpdate();
          if (isset($this->internalDataListData[0])) {
              $this->internalDataListUpdateValueIfNeeded($this->internalDataListData, sizeof($this->internalDataListData) - 1);
              return array_pop($this->internalDataListData);
          }
          return null;
      }
code_tokens: public function pop ( ) { $ this -> internalDataListUpdate ( ) ; if ( isset ( $ this -> internalDataListData [ 0 ] ) ) { $ this -> internalDataListUpdateValueIfNeeded ( $ this -> internalDataListData , sizeof ( $ this -> internalDataListData ) - 1 ) ; return array_pop ( $ this -> internalDataListData ) ; } return null ; }
docstring: Pops an object off the end of the list.
  
  @return object|null Returns the popped object or null if the list is empty.
  @throws \InvalidArgumentException
docstring_tokens: Pops an object off the end of the list .