Function bom 

pub fn bom(
    reader: &Reader<'_>,
    file: &str,
    structure: Structure,
) -> GeopResult<Bom>

The bill of materials of the part reader reads, the program of the file file, laid out as structure says. A part placed is listed by its own title and designation, if it has them (see crate::parameters::Properties).

The part’s own bodies — those it is modelled with besides what it places — are a line of their own, named after its file: for a part that places nothing, that line is the whole bill.