Type Alias Clue 

pub type Clue = Vec<u8>;

A single row or column clue: run-lengths of consecutive filled cells, e.g. [3, 1] for a line shaped ###.#. An all-empty line’s clue is [0], never an empty vec, so it can be compared directly against a freshly-computed clue from the player’s current grid.

Aliased Type

pub struct Clue { /* private fields */ }