php - 空になるまで増分変数を抽出するようにするにはどうすればよいですか?

Question

extract ($wddx_0, EXTR_PREFIX_ALL, "wddx0");
extract ($wddx_1, EXTR_PREFIX_ALL, "wddx1");
extract ($wddx_2, EXTR_PREFIX_ALL, "wddx2");
extract ($wddx_3, EXTR_PREFIX_ALL, "wddx3");
extract ($wddx_4, EXTR_PREFIX_ALL, "wddx4");
extract ($wddx_5, EXTR_PREFIX_ALL, "wddx5");
extract ($wddx_6, EXTR_PREFIX_ALL, "wddx6");
extract ($wddx_7, EXTR_PREFIX_ALL, "wddx7");
extract ($wddx_8, EXTR_PREFIX_ALL, "wddx8");
extract ($wddx_9, EXTR_PREFIX_ALL, "wddx9");
extract ($wddx_10, EXTR_PREFIX_ALL, "wddx10");
extract ($wddx_11, EXTR_PREFIX_ALL, "wddx11");
extract ($wddx_12, EXTR_PREFIX_ALL, "wddx12");
extract ($wddx_13, EXTR_PREFIX_ALL, "wddx13");
extract ($wddx_14, EXTR_PREFIX_ALL, "wddx14");
extract ($wddx_15, EXTR_PREFIX_ALL, "wddx15");
extract ($wddx_16, EXTR_PREFIX_ALL, "wddx16");
extract ($wddx_17, EXTR_PREFIX_ALL, "wddx17");
extract ($wddx_18, EXTR_PREFIX_ALL, "wddx18");
extract ($wddx_19, EXTR_PREFIX_ALL, "wddx19");

これを動的にして、空の変数になるまで最初と最後の数字を変更し続け、その時点で停止して次の関数を実行することはできますか?