What's the best way to chain if-elseif-else calls with elseif-else hidden by default?

Question

OOP

So it seems to work, only by default you need to hide the elseif, else methods. how can it be done better?

class BaseLol {
  #isNextIf = false;

  public if(condition: boolean) {
    if (condition) {
      this.#isNextIf = false;
    } else {
      this.#isNextIf = true;
    }
    return this as Omit<this, "if">;
  }

  public elseif(condition: boolean) {
    if (this.#isNextIf && condition) {
      this.#isNextIf = false;
    }
    return this;
  }

  public else() {
    if (this.#isNextIf) {
      this.#isNextIf = false;
    }
    return this as Omit<this, "else" | "elseif">;
  }
}

Answer 1

if (condition) {
      this.#isNextIf = false;
} else {
      this.#isNextIf = true;
}
// this.#isNextIf = !condition;

if (this.#isNextIf && condition) {
      this.#isNextIf = false;
}
// this.#isNextIf &= !condition;

if (this.#isNextIf) {
      this.#isNextIf = false;
}
// this.#isNextIf = false;