macro_rules! for_base_ops {
    (
        T = $types:tt;
        type Lhs = Simd<T, N>;
        type Rhs = Simd<T, N>;
        type Output = $out:ident;
        impl $op:ident::$call:ident
            $inner:tt
        $($rest:tt)*
    ) => { ... };
    ($($done:tt)*) => { ... };
}
🔬This is a nightly-only experimental API. (portable_simd #86656)