{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# 例外"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## 例外の捕捉"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "以下のコードは数値を$0$で割るため、実行するとエラー（例外）が発生する。"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {
    "tags": [
     "raises-exception"
    ]
   },
   "outputs": [
    {
     "ename": "ZeroDivisionError",
     "evalue": "float division by zero",
     "output_type": "error",
     "traceback": [
      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[0;31mZeroDivisionError\u001b[0m                         Traceback (most recent call last)",
      "\u001b[0;32m/tmp/ipykernel_2793/4032807262.py\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0;36m2.\u001b[0m \u001b[0;34m/\u001b[0m \u001b[0;36m0\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[0;31mZeroDivisionError\u001b[0m: float division by zero"
     ]
    }
   ],
   "source": [
    "2. / 0"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "プログラム中でエラーが発生したときは、例外クラスのオブジェクトが作成・送出される。例えば、上の例では[ZeroDivisionError](https://docs.python.org/ja/3/library/exceptions.html#ZeroDivisionError)という例外クラスのオブジェクトが`'float division by zero'`というメッセージ付きで送出されている。\n",
    "\n",
    "プログラムの実行中に例外が発生するとPythonインタプリタの実行が直ちに停止されるが、 [try](https://docs.python.org/ja/3/reference/compound_stmts.html#the-try-statement)文およびexcept節を用いて、例外をプログラム中で捕捉することも可能である。"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "ゼロ除算: float division by zero\n"
     ]
    }
   ],
   "source": [
    "try:\n",
    "    2. / 0\n",
    "except ZeroDivisionError as e:\n",
    "    print('ゼロ除算:', e)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "try文を用いても、except節で指定した例外クラス以外の例外が発生した場合は、except節は実行されずPythonインタプリタの実行が止まってしまう。以下のプログラムで発生する例外は[OverflowError](https://docs.python.org/ja/3/library/exceptions.html#OverflowError)であるため、ZeroDivisionErrorに関するexcept節では捕捉しきれない。"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {
    "tags": [
     "raises-exception"
    ]
   },
   "outputs": [
    {
     "ename": "OverflowError",
     "evalue": "(34, 'Numerical result out of range')",
     "output_type": "error",
     "traceback": [
      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[0;31mOverflowError\u001b[0m                             Traceback (most recent call last)",
      "\u001b[0;32m/tmp/ipykernel_2793/1994322563.py\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[1;32m      1\u001b[0m \u001b[0;32mtry\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 2\u001b[0;31m     \u001b[0;36m2.\u001b[0m \u001b[0;34m**\u001b[0m \u001b[0;36m1024\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m      3\u001b[0m \u001b[0;32mexcept\u001b[0m \u001b[0mZeroDivisionError\u001b[0m \u001b[0;32mas\u001b[0m \u001b[0me\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m      4\u001b[0m     \u001b[0mprint\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0me\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
      "\u001b[0;31mOverflowError\u001b[0m: (34, 'Numerical result out of range')"
     ]
    }
   ],
   "source": [
    "try:\n",
    "    2. ** 1024\n",
    "except ZeroDivisionError as e:\n",
    "    print(e)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "except節を複数並べることで、異なる複数の例外に対する処理を記述できる。"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "オーバーフロー: (34, 'Numerical result out of range')\n"
     ]
    }
   ],
   "source": [
    "try:\n",
    "    2. ** 1024\n",
    "except ZeroDivisionError as e:\n",
    "    print('ゼロ除算:', e)\n",
    "except OverflowError as e:\n",
    "    print('オーバーフロー:', e)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "ゼロ除算: float division by zero\n"
     ]
    }
   ],
   "source": [
    "try:\n",
    "    2. / 0\n",
    "except ZeroDivisionError as e:\n",
    "    print('ゼロ除算:', e)\n",
    "except OverflowError as e:\n",
    "    print('オーバーフロー:', e)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "except節に例外クラスをタプルとしてまとめることで、異なる複数の例外に対する処理をまとめて記述できる。"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "例外: <class 'OverflowError'> (34, 'Numerical result out of range')\n"
     ]
    }
   ],
   "source": [
    "try:\n",
    "    2. ** 1024\n",
    "except (ZeroDivisionError, OverflowError) as e:\n",
    "    print('例外:', type(e), e)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "例外: <class 'ZeroDivisionError'> float division by zero\n"
     ]
    }
   ],
   "source": [
    "try:\n",
    "    2. / 0\n",
    "except (ZeroDivisionError, OverflowError) as e:\n",
    "    print('例外:', type(e), e)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "なお、ZeroDivisionErrorやOverflowErrorなどの組み込み例外の基底クラスは[Exception](https://docs.python.org/ja/3/library/exceptions.html#Exception)であるため、except節でExceptionクラスを指定すると、異なる種類の例外をまとめて捕捉できる。"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "例外: <class 'OverflowError'> (34, 'Numerical result out of range')\n"
     ]
    }
   ],
   "source": [
    "try:\n",
    "    2. ** 1024\n",
    "except Exception as e:\n",
    "    print('例外:', type(e), e)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "例外: <class 'ZeroDivisionError'> float division by zero\n"
     ]
    }
   ],
   "source": [
    "try:\n",
    "    2. / 0\n",
    "except Exception as e:\n",
    "    print('例外:', type(e), e)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## 例外の送出"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "[raise](https://docs.python.org/ja/3/reference/simple_stmts.html#raise)文を用いると、自分で実装したコードの中から例外を送出できる。"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [],
   "source": [
    "def timestamp(hour, minute, second):\n",
    "    if hour < 0 or 24 <= hour:\n",
    "        raise ValueError(\"引数hourは0 <= hour < 24を満たす必要があります\")\n",
    "    if minute < 0 or 60 <= minute:\n",
    "        raise ValueError(\"引数minuteは0 <= minute < 60を満たす必要があります\")\n",
    "    if second < 0 or 60 <= second:\n",
    "        raise ValueError(\"引数secondは0 <= second < 60を満たす必要があります\")\n",
    "    return hour * 3600 + minute * 60 + second"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {
    "tags": [
     "raises-exception"
    ]
   },
   "outputs": [
    {
     "ename": "ValueError",
     "evalue": "引数secondは0 <= second < 60を満たす必要があります",
     "output_type": "error",
     "traceback": [
      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[0;31mValueError\u001b[0m                                Traceback (most recent call last)",
      "\u001b[0;32m/tmp/ipykernel_2793/3015373880.py\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0mtimestamp\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;36m2\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0;36m43\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0;36m70\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[0;32m/tmp/ipykernel_2793/1510188508.py\u001b[0m in \u001b[0;36mtimestamp\u001b[0;34m(hour, minute, second)\u001b[0m\n\u001b[1;32m      5\u001b[0m         \u001b[0;32mraise\u001b[0m \u001b[0mValueError\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m\"引数minuteは0 <= minute < 60を満たす必要があります\"\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m      6\u001b[0m     \u001b[0;32mif\u001b[0m \u001b[0msecond\u001b[0m \u001b[0;34m<\u001b[0m \u001b[0;36m0\u001b[0m \u001b[0;32mor\u001b[0m \u001b[0;36m60\u001b[0m \u001b[0;34m<=\u001b[0m \u001b[0msecond\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 7\u001b[0;31m         \u001b[0;32mraise\u001b[0m \u001b[0mValueError\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m\"引数secondは0 <= second < 60を満たす必要があります\"\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m      8\u001b[0m     \u001b[0;32mreturn\u001b[0m \u001b[0mhour\u001b[0m \u001b[0;34m*\u001b[0m \u001b[0;36m3600\u001b[0m \u001b[0;34m+\u001b[0m \u001b[0mminute\u001b[0m \u001b[0;34m*\u001b[0m \u001b[0;36m60\u001b[0m \u001b[0;34m+\u001b[0m \u001b[0msecond\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
      "\u001b[0;31mValueError\u001b[0m: 引数secondは0 <= second < 60を満たす必要があります"
     ]
    }
   ],
   "source": [
    "timestamp(2, 43, 70)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "関数の呼び出し側にtry文を埋め込み、例外を捕捉することも可能である。"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 12,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "例外: <class 'ValueError'> 引数hourは0 <= hour < 24を満たす必要があります\n"
     ]
    }
   ],
   "source": [
    "try:\n",
    "    timestamp(48, 0, 0)\n",
    "except Exception as e:\n",
    "    print('例外:', type(e), e)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "例外クラスを自分で定義することもできる。ユーザ定義の例外クラスは[Exception](https://docs.python.org/ja/3/library/exceptions.html#Exception)を継承する必要がある。"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 13,
   "metadata": {},
   "outputs": [],
   "source": [
    "class TimestampError(Exception):\n",
    "    pass\n",
    "\n",
    "def timestamp(hour, minute, second):\n",
    "    if hour < 0 or 24 <= hour:\n",
    "        raise TimestampError(\"引数hourは0 <= hour < 24を満たす必要があります\")\n",
    "    if minute < 0 or 60 <= minute:\n",
    "        raise TimestampError(\"引数minuteは0 <= minute < 60を満たす必要があります\")\n",
    "    if second < 0 or 60 <= second:\n",
    "        raise TimestampError(\"引数secondは0 <= second < 60を満たす必要があります\")\n",
    "    return hour * 3600 + minute * 60 + second"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {
    "tags": [
     "raises-exception"
    ]
   },
   "outputs": [
    {
     "ename": "TimestampError",
     "evalue": "引数minuteは0 <= minute < 60を満たす必要があります",
     "output_type": "error",
     "traceback": [
      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[0;31mTimestampError\u001b[0m                            Traceback (most recent call last)",
      "\u001b[0;32m/tmp/ipykernel_2793/3588777746.py\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0mtimestamp\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;36m1\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0;36m95\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0;36m22\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[0;32m/tmp/ipykernel_2793/4188596422.py\u001b[0m in \u001b[0;36mtimestamp\u001b[0;34m(hour, minute, second)\u001b[0m\n\u001b[1;32m      6\u001b[0m         \u001b[0;32mraise\u001b[0m \u001b[0mTimestampError\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m\"引数hourは0 <= hour < 24を満たす必要があります\"\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m      7\u001b[0m     \u001b[0;32mif\u001b[0m \u001b[0mminute\u001b[0m \u001b[0;34m<\u001b[0m \u001b[0;36m0\u001b[0m \u001b[0;32mor\u001b[0m \u001b[0;36m60\u001b[0m \u001b[0;34m<=\u001b[0m \u001b[0mminute\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 8\u001b[0;31m         \u001b[0;32mraise\u001b[0m \u001b[0mTimestampError\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m\"引数minuteは0 <= minute < 60を満たす必要があります\"\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m      9\u001b[0m     \u001b[0;32mif\u001b[0m \u001b[0msecond\u001b[0m \u001b[0;34m<\u001b[0m \u001b[0;36m0\u001b[0m \u001b[0;32mor\u001b[0m \u001b[0;36m60\u001b[0m \u001b[0;34m<=\u001b[0m \u001b[0msecond\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m     10\u001b[0m         \u001b[0;32mraise\u001b[0m \u001b[0mTimestampError\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m\"引数secondは0 <= second < 60を満たす必要があります\"\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
      "\u001b[0;31mTimestampError\u001b[0m: 引数minuteは0 <= minute < 60を満たす必要があります"
     ]
    }
   ],
   "source": [
    "timestamp(1, 95, 22)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "今回の引数チェックの場合、`hour`, `minute`, `second`のそれぞれに対し、別の例外クラスを定義するのも一案である。"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
   "metadata": {},
   "outputs": [],
   "source": [
    "class TimestampError(Exception):\n",
    "    pass\n",
    "\n",
    "class TimestampHourError(TimestampError):\n",
    "    pass\n",
    "\n",
    "class TimestampMinuteError(TimestampError):\n",
    "    pass\n",
    "\n",
    "class TimestampSecondError(TimestampError):\n",
    "    pass\n",
    "\n",
    "def timestamp(hour, minute, second):\n",
    "    if hour < 0 or 24 <= hour:\n",
    "        raise TimestampHourError(\"引数hourは0 <= hour < 24を満たす必要があります\")\n",
    "    if minute < 0 or 60 <= minute:\n",
    "        raise TimestampMinuteError(\"引数minuteは0 <= minute < 60を満たす必要があります\")\n",
    "    if second < 0 or 60 <= second:\n",
    "        raise TimestampSecondError(\"引数secondは0 <= second < 60を満たす必要があります\")\n",
    "    return hour * 3600 + minute * 60 + second"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 16,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "例外: <class '__main__.TimestampMinuteError'> 引数minuteは0 <= minute < 60を満たす必要があります\n"
     ]
    }
   ],
   "source": [
    "try:\n",
    "    timestamp(2, 68, 0)\n",
    "except Exception as e:\n",
    "    print('例外:', type(e), e)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "なお、デバッグ目的であれば[assert](https://docs.python.org/ja/3/reference/simple_stmts.html#the-assert-statement)文を使い、引数の値をチェック（テスト）して、違反していたら[AssertionError](https://docs.python.org/ja/3/library/exceptions.html#AssertionError)を送出することもできる。"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 17,
   "metadata": {},
   "outputs": [],
   "source": [
    "def timestamp(hour, minute, second):\n",
    "    assert 0 <= hour < 24, \"引数hourは0 <= hour < 24を満たす必要があります\"\n",
    "    assert 0 <= minute < 60, \"引数minuteは0 <= minute < 60を満たす必要があります\"\n",
    "    assert 0 <= second < 60, \"引数secondは0 <= second < 60を満たす必要があります\"\n",
    "    return hour * 3600 + minute * 60 + second"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 18,
   "metadata": {
    "tags": [
     "raises-exception"
    ]
   },
   "outputs": [
    {
     "ename": "AssertionError",
     "evalue": "引数secondは0 <= second < 60を満たす必要があります",
     "output_type": "error",
     "traceback": [
      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[0;31mAssertionError\u001b[0m                            Traceback (most recent call last)",
      "\u001b[0;32m/tmp/ipykernel_2793/3015373880.py\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0mtimestamp\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;36m2\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0;36m43\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0;36m70\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[0;32m/tmp/ipykernel_2793/3965020354.py\u001b[0m in \u001b[0;36mtimestamp\u001b[0;34m(hour, minute, second)\u001b[0m\n\u001b[1;32m      2\u001b[0m     \u001b[0;32massert\u001b[0m \u001b[0;36m0\u001b[0m \u001b[0;34m<=\u001b[0m \u001b[0mhour\u001b[0m \u001b[0;34m<\u001b[0m \u001b[0;36m24\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0;34m\"引数hourは0 <= hour < 24を満たす必要があります\"\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m      3\u001b[0m     \u001b[0;32massert\u001b[0m \u001b[0;36m0\u001b[0m \u001b[0;34m<=\u001b[0m \u001b[0mminute\u001b[0m \u001b[0;34m<\u001b[0m \u001b[0;36m60\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0;34m\"引数minuteは0 <= minute < 60を満たす必要があります\"\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 4\u001b[0;31m     \u001b[0;32massert\u001b[0m \u001b[0;36m0\u001b[0m \u001b[0;34m<=\u001b[0m \u001b[0msecond\u001b[0m \u001b[0;34m<\u001b[0m \u001b[0;36m60\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0;34m\"引数secondは0 <= second < 60を満たす必要があります\"\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m      5\u001b[0m     \u001b[0;32mreturn\u001b[0m \u001b[0mhour\u001b[0m \u001b[0;34m*\u001b[0m \u001b[0;36m3600\u001b[0m \u001b[0;34m+\u001b[0m \u001b[0mminute\u001b[0m \u001b[0;34m*\u001b[0m \u001b[0;36m60\u001b[0m \u001b[0;34m+\u001b[0m \u001b[0msecond\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
      "\u001b[0;31mAssertionError\u001b[0m: 引数secondは0 <= second < 60を満たす必要があります"
     ]
    }
   ],
   "source": [
    "timestamp(2, 43, 70)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## よく見かける例外"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "文法エラー"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "metadata": {
    "tags": [
     "raises-exception"
    ]
   },
   "outputs": [
    {
     "ename": "SyntaxError",
     "evalue": "invalid syntax (3671002116.py, line 1)",
     "output_type": "error",
     "traceback": [
      "\u001b[0;36m  File \u001b[0;32m\"/tmp/ipykernel_2793/3671002116.py\"\u001b[0;36m, line \u001b[0;32m1\u001b[0m\n\u001b[0;31m    2 / / 1\u001b[0m\n\u001b[0m        ^\u001b[0m\n\u001b[0;31mSyntaxError\u001b[0m\u001b[0;31m:\u001b[0m invalid syntax\n"
     ]
    }
   ],
   "source": [
    "2 / / 1"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "インデントの間違い"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 20,
   "metadata": {
    "tags": [
     "raises-exception"
    ]
   },
   "outputs": [
    {
     "ename": "IndentationError",
     "evalue": "expected an indented block (2214768420.py, line 3)",
     "output_type": "error",
     "traceback": [
      "\u001b[0;36m  File \u001b[0;32m\"/tmp/ipykernel_2793/2214768420.py\"\u001b[0;36m, line \u001b[0;32m3\u001b[0m\n\u001b[0;31m    print('even')\u001b[0m\n\u001b[0m    ^\u001b[0m\n\u001b[0;31mIndentationError\u001b[0m\u001b[0;31m:\u001b[0m expected an indented block\n"
     ]
    }
   ],
   "source": [
    "for i in range(10):\n",
    "    if i % 2 == 0:\n",
    "    print('even')"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "オーバーフロー"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 21,
   "metadata": {
    "tags": [
     "raises-exception"
    ]
   },
   "outputs": [
    {
     "ename": "OverflowError",
     "evalue": "(34, 'Numerical result out of range')",
     "output_type": "error",
     "traceback": [
      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[0;31mOverflowError\u001b[0m                             Traceback (most recent call last)",
      "\u001b[0;32m/tmp/ipykernel_2793/997473611.py\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0;36m2.\u001b[0m \u001b[0;34m**\u001b[0m \u001b[0;36m1024\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[0;31mOverflowError\u001b[0m: (34, 'Numerical result out of range')"
     ]
    }
   ],
   "source": [
    "2. ** 1024"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "未定義の変数"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 22,
   "metadata": {
    "tags": [
     "raises-exception"
    ]
   },
   "outputs": [
    {
     "ename": "NameError",
     "evalue": "name 'a' is not defined",
     "output_type": "error",
     "traceback": [
      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[0;31mNameError\u001b[0m                                 Traceback (most recent call last)",
      "\u001b[0;32m/tmp/ipykernel_2793/188921875.py\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0ma\u001b[0m \u001b[0;34m*\u001b[0m \u001b[0;36m2\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[0;31mNameError\u001b[0m: name 'a' is not defined"
     ]
    }
   ],
   "source": [
    "a * 2"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "範囲外のインデックス"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 23,
   "metadata": {
    "tags": [
     "raises-exception"
    ]
   },
   "outputs": [
    {
     "ename": "IndexError",
     "evalue": "list index out of range",
     "output_type": "error",
     "traceback": [
      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[0;31mIndexError\u001b[0m                                Traceback (most recent call last)",
      "\u001b[0;32m/tmp/ipykernel_2793/3042274859.py\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[1;32m      1\u001b[0m \u001b[0mx\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0;34m[\u001b[0m\u001b[0;36m1\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0;36m2\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0;36m3\u001b[0m\u001b[0;34m]\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 2\u001b[0;31m \u001b[0mx\u001b[0m\u001b[0;34m[\u001b[0m\u001b[0;36m4\u001b[0m\u001b[0;34m]\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[0;31mIndexError\u001b[0m: list index out of range"
     ]
    }
   ],
   "source": [
    "x = [1, 2, 3]\n",
    "x[4]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "キーが見つからない"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 24,
   "metadata": {
    "tags": [
     "raises-exception"
    ]
   },
   "outputs": [
    {
     "ename": "KeyError",
     "evalue": "'four'",
     "output_type": "error",
     "traceback": [
      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[0;31mKeyError\u001b[0m                                  Traceback (most recent call last)",
      "\u001b[0;32m/tmp/ipykernel_2793/1027427460.py\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[1;32m      1\u001b[0m \u001b[0my\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0;34m{\u001b[0m\u001b[0;34m'one'\u001b[0m\u001b[0;34m:\u001b[0m \u001b[0;36m1\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0;34m'two'\u001b[0m\u001b[0;34m:\u001b[0m \u001b[0;36m2\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0;34m'three'\u001b[0m\u001b[0;34m:\u001b[0m \u001b[0;36m3\u001b[0m\u001b[0;34m}\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 2\u001b[0;31m \u001b[0my\u001b[0m\u001b[0;34m[\u001b[0m\u001b[0;34m'four'\u001b[0m\u001b[0;34m]\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[0;31mKeyError\u001b[0m: 'four'"
     ]
    }
   ],
   "source": [
    "y = {'one': 1, 'two': 2, 'three': 3}\n",
    "y['four']"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "型の不整合"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 25,
   "metadata": {
    "tags": [
     "raises-exception"
    ]
   },
   "outputs": [
    {
     "ename": "TypeError",
     "evalue": "can only concatenate list (not \"dict\") to list",
     "output_type": "error",
     "traceback": [
      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[0;31mTypeError\u001b[0m                                 Traceback (most recent call last)",
      "\u001b[0;32m/tmp/ipykernel_2793/978381659.py\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0mx\u001b[0m \u001b[0;34m+\u001b[0m \u001b[0my\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[0;31mTypeError\u001b[0m: can only concatenate list (not \"dict\") to list"
     ]
    }
   ],
   "source": [
    "x + y"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "ファイルが見つからない"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 26,
   "metadata": {
    "tags": [
     "raises-exception"
    ]
   },
   "outputs": [
    {
     "ename": "FileNotFoundError",
     "evalue": "[Errno 2] No such file or directory: 'hoge.txt'",
     "output_type": "error",
     "traceback": [
      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[0;31mFileNotFoundError\u001b[0m                         Traceback (most recent call last)",
      "\u001b[0;32m/tmp/ipykernel_2793/1539795522.py\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0mopen\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m'hoge.txt'\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[0;31mFileNotFoundError\u001b[0m: [Errno 2] No such file or directory: 'hoge.txt'"
     ]
    }
   ],
   "source": [
    "open('hoge.txt')"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
    "tags": [
     "remove-cell"
    ]
   },
   "source": [
    "---\n",
    "\n",
    "[Python早見帳](https://chokkan.github.io/python/) © Copyright 2020-2022 by [岡崎 直観 (Naoaki Okazaki)](https://www.chokkan.org/). この作品は<a rel=\"license\" href=\"http://creativecommons.org/licenses/by-nc-nd/4.0/\">クリエイティブ・コモンズ 表示 - 非営利 - 改変禁止 4.0 国際 ライセンス</a>の下に提供されています。<a rel=\"license\" href=\"http://creativecommons.org/licenses/by-nc-nd/4.0/\"><img alt=\"クリエイティブ・コモンズ・ライセンス\" style=\"border-width:0\" src=\"https://i.creativecommons.org/l/by-nc-nd/4.0/80x15.png\" /></a>"
   ]
  }
 ],
 "metadata": {
  "@context": {
   "CreativeWork": "http://schema.org/CreativeWork",
   "Organization": "http://schema.org/Organization",
   "Person": "http://schema.org/Person",
   "author": "http://schema.org/author",
   "copyrightHolder": "http://schema.org/copyrightHolder",
   "copyrightYear": "http://schema.org/copyrightYear",
   "license": "http://schema.org/license",
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  "@type": "CreativeWork",
  "author": [
   {
    "@type": "Person",
    "name": "Naoaki Okazaki",
    "url": "https://www.chokkan.org/"
   }
  ],
  "copyrightHolder": [
   {
    "@type": "Person",
    "name": "Naoaki Okazaki",
    "url": "https://www.chokkan.org/"
   }
  ],
  "copyrightYear": 2022,
  "kernelspec": {
   "display_name": "Python 3 (ipykernel)",
   "language": "python",
   "name": "python3"
  },
  "language_info": {
   "codemirror_mode": {
    "name": "ipython",
    "version": 3
   },
   "file_extension": ".py",
   "mimetype": "text/x-python",
   "name": "python",
   "nbconvert_exporter": "python",
   "pygments_lexer": "ipython3",
   "version": "3.8.10"
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  "license": "https://creativecommons.org/licenses/by-nc-nd/4.0/deed.ja",
  "title": "Python早見帳"
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