Function common_names 

pub fn common_names(
    cardinality: u8,
    forte_class: u8,
    inversion: Option<i8>,
) -> Result<Option<Vec<&'static str>>, Error>

What the set class is commonly called, where it is called anything: music21’s addressToCommonNames.

More than one name comes back where more than one is in use, and nothing where the class has no common name. The names take no account of spelling or inversion, so a minor triad answers “major triad”; Chord::common_name is the one that reads the chord as it is written.

Errors

When the address names no set class.