// Module B authors a DIFFERENT same-name chain: `M :: 10`, `K :: M + 1` (= 11).
// A shadow of A's `M`/`K`. Each `K`'s RHS leaf resolves to its own source's `M`,
// so the dimension fold gives B's length 11 — never A's via the global map.
M :: 10;
K :: M + 1;
b_val :: () -> s64 { return K; }
b_len :: () -> s64 {
    arr : [K]u8 = ---;
    return arr.len;
}