src/DataDefinition/ModelRelationship/FilterBuilder/FilterBuilderWithChildren.php
public function first()
    {
        $this->index = \count($this->children) ? 0 : (-1);

        if ($this->index === -1) {
            return null;
        }

        return $this->current();
    }
public function first()
    {
        $this->index = \count($this->children) ? 0 : (-1);

        if ($this->index === -1) {
            return null;
        }

        return $this->current();
    }
public function first ( ) { $ this -> index = \ count ( $ this -> children ) ? 0 : ( - 1 ) ; if ( $ this -> index === - 1 ) { return null ; } return $ this -> current ( ) ; }
Rewind the Iterator to the first element and return it.

@return BaseFilterBuilder
Rewind the Iterator to the first element and return it .