pub fn euler_handle_native(handle: u32) -> Result<EulerReport, String>Expand description
Closedness and Euler parity of a resident solid — the THIRD check
validate() does not make on its own. Its Euler comparison reduces, on a
freshly derived solid, to exactly “is the characteristic even”, and it is
switched off on any solid carrying a degenerate edge; this asks the question
directly and on every solid. Pure counting, one registry borrow.