Something
public text v1 · immutable$if([%composer%],
$if([%artist%], [%composer%] & [%artist%], [%composer%]),
$if([%artist%], %artist%, no information))$if([%composer%],
$if([%artist%], [%composer%] & [%artist%], [%composer%]),
$if([%artist%], %artist%, no information))