Function new_infinitesimal 

pub fn new_infinitesimal<V: TowerValue>(
    name: &str,
    modulus: u64,
    allowed: &[u64],
) -> Result<V, String>

The program’s infinitesimal: Let <name> be an infinitesimal …, its reciprocal’s residues modulo modulus limited to allowed (the parser has already intersected the stated facts), or the contradiction refused when nothing is allowed.