law shaped_len
import minebender-game@1.0.0.0/proof_lists.bend as ProofListsimport Base
import minebender-game@1.0.0.0/types.bend as T
import minebender-game@1.0.0.0/board.bend as B
163law shaped_len:
164 for -A: Data
165 for +w: Nat
166 for +h: Nat
167 for +g: T.Grid(A)
168 for sh: {B.shaped(A, w, h, g) == True{} : Bool}
169 {List.length(&2, List<&2, A>, g) == h : Nat}