the_author( string $deprecated = '', bool $deprecated_echo = true )

Source

File: wp-includes/author-template.php

function the_author( $deprecated = '', $deprecated_echo = true ) {
	if ( ! empty( $deprecated ) ) {
		_deprecated_argument( __FUNCTION__, '2.1.0' );
	}

	if ( true !== $deprecated_echo ) {
		_deprecated_argument(
			__FUNCTION__,
			'1.5.0',
			sprintf(
				/* translators: %s: get_the_author() */
				__( 'Use %s instead if you do not want the value echoed.' ),
				'<code>get_the_author()</code>'
			)
		);
	}

	if ( $deprecated_echo ) {
		echo get_the_author();
	}

	return get_the_author();
}