public function writeStartElement(string $elementName): self
    {
        $this->doWriteStartElement($elementName);
        $this->depth++;
        return $this;
    }
public function writeStartElement(string $elementName): self
    {
        $this->doWriteStartElement($elementName);
        $this->depth++;
        return $this;
    }
public function writeStartElement ( string $ elementName ) : self { $ this -> doWriteStartElement ( $ elementName ) ; $ this -> depth ++ ; return $ this ; }
Write an opening tag

@param   string  $elementName
@return  \stubbles\xml\XmlStreamWriter
Write an opening tag