julia_15_question.ipynb

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    "請問下列兩段例外處理的程式碼，回答其輸出的結果為何？展開解答可看答案。\n",
    "\n",
    "> 建議先思考判斷後回答，不要直接執行程式看結果\n",
    "\n",
    "## Day 015 問題1：請問下列程式輸出的結果為何？\n",
    "\n",
    "- 13\n",
    "- 1\n",
    "- 2\n",
    "- 3"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
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     "text": [
      "13"
     ]
    }
   ],
   "source": [
    "function foo()\n",
    "    try\n",
    "        print(1)\n",
    "    catch ex\n",
    "        print(2)\n",
    "    finally\n",
    "        print(3)\n",
    "    end\n",
    "end\n",
    "\n",
    "foo()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<details>\n",
    "<summary>展開解答</summary>\n",
    "<br>\n",
    "<h3>13</h3><br />\n",
    "【解釋】上面的程式可正常執行無異常狀況發生，所以會印出 try 區塊中的內容，而且由於 finally 一定會執行，所以也會印出。\n",
    "</details>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## 問題2：請問下列程式輸出的結果為何？\n",
    "\n",
    "- 1\n",
    "- 2\n",
    "- 23\n",
    "- 3"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "3"
      ]
     },
     "execution_count": 2,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "function foo()\n",
    "    try\n",
    "        log(-10)\n",
    "        return 1\n",
    "    catch ex\n",
    "        return 2\n",
    "    finally\n",
    "        return 3\n",
    "    end\n",
    "end\n",
    "\n",
    "foo()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<details>\n",
    "<summary>展開解答</summary>\n",
    "<br>\n",
    "<h3>3</h3><br />\n",
    "【解釋】上面的程式執行會發生異常，雖然會進入 catch 區塊，但由於 finally 一定會執行，而回傳值僅保留最後一個 return 的回傳值，所以答案為 3。\n",
    "</details>"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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