law within_self
import minebender-game@1.0.0.0/proof_gen.bend as ProofGenimport Base
import minebender-game@1.0.0.0/types.bend as T
import minebender-game@1.0.0.0/board.bend as B
267# A cell is within one step of itself.
268law within_self:
269 for +p: T.Pos
270 {B.within_one(p, p) == True{} : Bool}