Errors and exceptions

Both errors and exceptions indicate that something has gone wrong in a program, but an exception is a specific type of error that Python can handle.

BaseException is the top-most class for all exceptions in Python.

BaseException

│

├── Exception

│   ├── ValueError

│   ├── TypeError

│   ├── IndexError

│   ├── KeyError

│   └── ZeroDivisionError

│

├── SystemExit

├── KeyboardInterrupt

└── GeneratorExit

A stack trace is a report that shows the sequence of function calls that led to an error.

It helps programmers answer:

"Where did the error happen, and how did the program get there?"

A nested call happens when one function calls another function, which may call another function, and so on.

def c():

    print("In c")

def b():

    c()

def a():

    b()

execution flow

a()

 ↓

b()

 ↓

c()

Here, a() calls b(), and b() calls c(). These are nested function calls.

intimidating: frightening in a way that makes a person feel less confident

try:

    1/0

except Exception as e:

    print(type(e))

ZeroDivisionError is a subclass of Exception

The variable e refers to the exception object.

e = exception object

type(e) = ZeroDivisionError

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