Common Built-in Exceptions

Exception	Raised when	Example
`SyntaxError`	the code breaks Python's grammar (before it runs)	`if x > 3 print(x)`
`ValueError`	the type is right but the value is not	`int("abc")`
`TypeError`	an operation gets the wrong type	`"5" + 2`
`ZeroDivisionError`	division or modulo by zero	`7 % 0`
`NameError`	a name is not defined	`print(totl)`
`IndexError`	a sequence index is out of range	`[1, 2][5]`
`KeyError`	a dictionary key is missing	`{"a": 1}["b"]`
`FileNotFoundError`	opening a file that does not exist for reading	`open("none.txt")`
`EOFError`	input() or pickle.load() reaches the end of the data	`pickle.load(f)` after the last record
`ImportError`	a module or name cannot be imported	`from math import square`

One except clause can catch several types written as a tuple, and as gives you the exception object with its message:

try:
    value = [10, 20, 30][int(input())]
except (ValueError, IndexError) as err:
    print("Bad position:", type(err).__name__)

Python exercise

Each input line is an expression a op b with integers and an operator +, -, *, / or %. Print the result of each, or the name of the exception it raises (ZeroDivisionError or ValueError). Stop at the line END.

ops = {"+": lambda a, b: a + b, "-": lambda a, b: a - b, "*": lambda a, b: a * b,
       "/": lambda a, b: a / b, "%": lambda a, b: a % b}
while True:
    line = input()
    if line == "END":
        break
    a, op, b = line.split()
    print(ops[op](int(a), int(b)))  # catch the errors and print their names

Notifications

Common Built-in Exceptions

Common Built-in Exceptions

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