Game.gen.left: def of minebender-game@1.0.0.0
Import: import minebender-game@1.0.0.0/game.bend as Game
Lines 194-200 of minebender-game@1.0.0.0/game.bend: https://jend.leeeet.dev/read.txt?path=minebender-game@1.0.0.0/game.bend&start_line=194&end_line=200

import Base
import minebender-game@1.0.0.0/types.bend as T

# How many cells of ps are outside the zone.
def gen.left(+z: Zone, ps: List<&2, T.Pos>) -> Nat:
  match ps:
    case Nil{}:
      0n
    case p <> t:
      Nat.add(Bool.pick(Nat, gen.out(z, p), 0n, 1n), gen.left(z, t))

Uses (7):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.pick
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.add
  https://jend.leeeet.dev/definition.txt?path=minebender-game@1.0.0.0/game.bend&name=Zone
  https://jend.leeeet.dev/definition.txt?path=minebender-game@1.0.0.0/game.bend&name=gen.out
  https://jend.leeeet.dev/definition.txt?path=minebender-game@1.0.0.0/types.bend&name=Pos