pub struct Shape {
pub height: usize,
pub width: usize,
}
pub trait Matrix: std::ops::IndexMut<(usize, usize)> {}
// impl<M: Matrix>
// crate::group_theory::Identity<crate::grouptheory::Additive>
// for Option<M> { fn identity() -> Self { None }
// }
pub trait SquareMatrix: Matrix {
fn identity() -> Self;
fn invert(&self) -> Self;
}
#[cfg(test)]
mod tests {
#[test]
fn test() {}
}