rest_handle_deprecated_argument() WordPress Function

The rest_handle_deprecated_argument() function is used to gracefully handle deprecated arguments in WordPress REST API requests. This function should be used whenever an argument is deprecated and replaced with a new one. deprecated The deprecated argument is the old argument that is being deprecated. This argument is no longer used and will be removed in a future version of WordPress. replacement The replacement argument is the new argument that should be used in its place. This argument should be used in all future REST API requests. This function allows for a smooth transition when an argument is deprecated and replaced with a new one. It is important to note that this function should only be used for deprecated arguments, and not for any other purpose.

rest_handle_deprecated_argument( string $function, string $message, string $version ) #

function rest_handle_deprecated_argument( $function, $message, $version ) {
	if ( ! WP_DEBUG || headers_sent() ) {
		return;
	}
	if ( $message ) {
		/* translators: 1: Function name, 2: WordPress version number, 3: Error message. */
		$string = sprintf( __( '%1$s (since %2$s; %3$s)' ), $function, $version, $message );
	} else {
		/* translators: 1: Function name, 2: WordPress version number. */
		$string = sprintf( __( '%1$s (since %2$s; no alternative available)' ), $function, $version );
	}

	header( sprintf( 'X-WP-DeprecatedParam: %s', $string ) );
}