{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Basic exception handling"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "An exception has occurred\n"
     ]
    }
   ],
   "source": [
    "class Calc:\n",
    "    def Inverse(self, num):\n",
    "        return 1/num\n",
    "\n",
    "try:\n",
    "    cal = Calc()\n",
    "    cal.Inverse(0)\n",
    "except Exception as err:\n",
    "    print(\"An exception has occurred\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Handling specific exceptions"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### The exception in below example will be caught by first except block"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "A zero division exception has occurred. Exception message - division by zero\n"
     ]
    }
   ],
   "source": [
    "try:\n",
    "    cal = Calc()\n",
    "    cal.Inverse(0)\n",
    "except ZeroDivisionError as zeroDivideError:\n",
    "    print(\"A zero division exception has occurred. Exception message -\", zeroDivideError)\n",
    "except Exception as err:\n",
    "    print(\"An exception has occurred -\", err)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### The exception in below example will be caught by second except block"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "An exception has occurred - object() takes no parameters\n"
     ]
    }
   ],
   "source": [
    "try:\n",
    "    cal = Calc(\"\")\n",
    "    cal.Inverse(0)\n",
    "except ZeroDivisionError as zeroDivideError:\n",
    "    print(\"A zero division exception has occurred. Exception message -\", zeroDivideError)\n",
    "except Exception as err:\n",
    "    print(\"An exception has occurred -\", err)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Raising an exception"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "An exception has occurred - Age can not be less than 18\n"
     ]
    }
   ],
   "source": [
    "class Student:\n",
    "    def setAge(self, age):\n",
    "        if(age < 18):\n",
    "            raise Exception(\"Age can not be less than 18\")\n",
    "        else:\n",
    "            self.age = age\n",
    "\n",
    "alice = Student()\n",
    "try:\n",
    "    alice.setAge(15)\n",
    "except Exception as error:\n",
    "    print(\"An exception has occurred -\", error)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# The else and finally block"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### The else block"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Age was assigned successfully!\n"
     ]
    }
   ],
   "source": [
    "bob = Student()\n",
    "try:\n",
    "    bob.setAge(20)\n",
    "except Exception as error:\n",
    "    print(\"An exception has occurred -\", error)\n",
    "else:\n",
    "    print(\"Age was assigned successfully!\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### The finally block"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Age was assigned successfully!\n",
      "Finally block - This always gets executed\n"
     ]
    }
   ],
   "source": [
    "bob = Student()\n",
    "try:\n",
    "    bob.setAge(20)\n",
    "except Exception as error:\n",
    "    print(\"An exception has occurred -\", error)\n",
    "else:\n",
    "    print(\"Age was assigned successfully!\")\n",
    "finally:\n",
    "    print(\"Finally block - This always gets executed\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# User defined exceptions"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Salary exception occurred -  Salary can't be less than 0\n"
     ]
    }
   ],
   "source": [
    "class SalaryError(Exception):\n",
    "    def __init__(self, arg):\n",
    "        self.arg = arg\n",
    "\n",
    "class Employee:\n",
    "    def setSalary(self, salary):\n",
    "        if(salary < 0):\n",
    "            raise SalaryError(\"Salary can't be less than 0\")\n",
    "        else:\n",
    "            self.salary = salary\n",
    "\n",
    "try:\n",
    "    chris = Employee()\n",
    "    chris.setSalary(-100)\n",
    "except SalaryError as error:\n",
    "    print(\"Salary exception occurred - \", error)"
   ]
  }
 ],
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