import fol

if __name__ == '__main__':
    kb = fol.kb.Kb()
    try:
        if False:
            kb.tell('Est(ALICE, X0, S0)')
            kb.tell('Proche(X0, X1)')
            kb.tell('Proche(X1, X2)')
            kb.tell('Proche(X2, X3)')
            kb.tell('Proche(X3, X4)')
            kb.tell('(Est(ALICE, x, s) & Proche(x, y)) -> Poss(go(x, y), s)')
            kb.tell('Poss(go(x, y), s) -> Est(ALICE, y, do(go(x, y), s))')
            answer = kb.ask('Est(ALICE, x, y)')
            print(answer)
        else:
            kb.tell('Friend(ALICE, BOB)')
            kb.tell('Friend(BOB, CLAIRE)')
            kb.tell('Friend(x, y) -> Friend(y, x)')
            kb.tell('(Friend(x, y) & Friend(y, z)) -> Friend(x, z)')
            answer = kb.ask('Friend(ALICE, x)')
            print(answer)

        # print('--------------------------------')
        # [print(b) for b in kb.base]

    except KeyboardInterrupt:
        pass