PYTHON

Raising Exceptions in Python

>>> raise KeyboardInterrupt
Traceback (most recent call last):
...
KeyboardInterrupt

>>> raise MemoryError("This is an argument")
Traceback (most recent call last):
...
MemoryError: This is an argument

>>> try:
...     x = int(input("Enter a positive integer: "))
...     if x <= 0:
...         raise ValueError("That is not a positive number!")
... except ValueError as y:
...     print(y)
...    
Enter a positive integer: -2
That is not a positive number!

python exceptions

#Syntax:

try:
	statement
except Exception as varname:
	statement
   
"""
Some specific exceptions (Lengthy but time-saving )- 

ArithmeticError - Raised when an error occurs in numeric calculations

AssertionError	- Raised when an assert statement fails

AttributeError	- Raised when attribute reference or assignment fails

Exception - Base class for all exceptions

EOFError -	Raised when the input() method hits an "end of file" condition (EOF)

FloatingPointError -	Raised when a floating point calculation fails

GeneratorExit -	Raised when a generator is closed (with the close() method)

ImportError -	Raised when an imported module does not exist

IndentationError -	Raised when indendation is not correct

IndexError -	Raised when an index of a sequence does not exist

KeyError -	Raised when a key does not exist in a dictionary

KeyboardInterrupt -	Raised when the user presses Ctrl+c, Ctrl+z or Delete

LookupError -	Raised when errors raised cant be found

MemoryError -	Raised when a program runs out of memory

NameError -	Raised when a variable does not exist

NotImplementedError -	Raised when an abstract method requires an inherited class to override the method

OSError -	Raised when a system related operation causes an error

OverflowError -	Raised when the result of a numeric calculation is too large

ReferenceError -	Raised when a weak reference object does not exist

RuntimeError -	Raised when an error occurs that do not belong to any specific expections

StopIteration -	Raised when the next() method of an iterator has no further values

SyntaxError -	Raised when a syntax error occurs

TabError -	Raised when indentation consists of tabs or spaces

SystemError -	Raised when a system error occurs

SystemExit -	Raised when the sys.exit() function is called

TypeError -	Raised when two different types are combined

UnboundLocalError -	Raised when a local variable is referenced before assignment

UnicodeError -	Raised when a unicode problem occurs

UnicodeEncodeError -	Raised when a unicode encoding problem occurs

UnicodeDecodeError -	Raised when a unicode decoding problem occurs

UnicodeTranslateError -	Raised when a unicode translation problem occurs

ValueError -	Raised when there is a wrong value in a specified data type

ZeroDivisionError -	Raised when the second operator in a division is zero

"""

python exceptions

while True:
    try:
        funds = float(input("Enter amount to transfer: "))
        if funds < 0:
            raise Exception("Please enter a positive value,")
        break
    except ValueError:
        print("Please enter a numeric value,")

python exceptions

BaseException
 +-- SystemExit
 +-- KeyboardInterrupt
 +-- GeneratorExit
 +-- Exception
      +-- StopIteration
      +-- StopAsyncIteration
      +-- ArithmeticError
      |    +-- FloatingPointError
      |    +-- OverflowError
      |    +-- ZeroDivisionError
      +-- AssertionError
      +-- AttributeError
      +-- BufferError
      +-- EOFError
      +-- ImportError
      |    +-- ModuleNotFoundError
      +-- LookupError
      |    +-- IndexError
      |    +-- KeyError
      +-- MemoryError
      +-- NameError
      |    +-- UnboundLocalError
      +-- OSError
      |    +-- BlockingIOError
      |    +-- ChildProcessError
      |    +-- ConnectionError
      |    |    +-- BrokenPipeError
      |    |    +-- ConnectionAbortedError
      |    |    +-- ConnectionRefusedError
      |    |    +-- ConnectionResetError
      |    +-- FileExistsError
      |    +-- FileNotFoundError
      |    +-- InterruptedError
      |    +-- IsADirectoryError
      |    +-- NotADirectoryError
      |    +-- PermissionError
      |    +-- ProcessLookupError
      |    +-- TimeoutError
      +-- ReferenceError
      +-- RuntimeError
      |    +-- NotImplementedError
      |    +-- RecursionError
      +-- SyntaxError
      |    +-- IndentationError
      |         +-- TabError
      +-- SystemError
      +-- TypeError
      +-- ValueError
      |    +-- UnicodeError
      |         +-- UnicodeDecodeError
      |         +-- UnicodeEncodeError
      |         +-- UnicodeTranslateError
      +-- Warning
           +-- DeprecationWarning
           +-- PendingDeprecationWarning
           +-- RuntimeWarning
           +-- SyntaxWarning
           +-- UserWarning
           +-- FutureWarning
           +-- ImportWarning
           +-- UnicodeWarning
           +-- BytesWarning
           +-- ResourceWarning

Raising Exceptions in Python

>>> raise KeyboardInterrupt
Traceback (most recent call last):
...
KeyboardInterrupt

>>> raise MemoryError("This is an argument")
Traceback (most recent call last):
...
MemoryError: This is an argument

>>> try:
...     a = int(input("Enter a positive integer: "))
...     if a <= 0:
...         raise ValueError("That is not a positive number!")
... except ValueError as ve:
...     print(ve)
...    
Enter a positive integer: -2
That is not a positive number!