assert keyword

Assert keyword

https://youtu.be/UORaySj-M2w

18^th Feb,2020.

Debugging:

Identifying and solving the errors (bugs) is called debugging.

Debugging:

Identifying the bug/issues (error) and solving (fixing) the issue/bug/errors is called Debugging.

Assert keyword:

def addition(a,b):

    return a-b

assert addition(4,2)==6,"Addition of two number=6"

assert addition(3,2)==5,"Addition of 3,2 is 5"

print("Addition of 4,2 numbers",addition(4,2))

print("Addition of 3,2 numbers",addition(3,2))

"""output:

assert addition(4,2)==6,"Addition of two number=6"

AssertionError: Addition of two number=6

Addition of 4,2 numbers 2

Addition of 3,2 numbers 1

"""

If I’m not using the assert in the above program, wrong output may be handed over to the client, because of the assert, it verifies the expected output other wise it will alert to the programmer.

def addition(a,b):

    return a+b

assert addition(4,2)==6,"Addition of two number=6"

assert addition(3,2)==5,"Addition of 3,2 is 5"

print("Addition of 4,2 numbers",addition(4,2))

print("Addition of 3,2 numbers",addition(3,2))

"""output:

Addition of 4,2 numbers 2

Addition of 3,2 numbers 1

Addition of 4,2 numbers 6

Addition of 3,2 numbers 5

Assert keyword is used to debugging (i.e resolving the error)

We will perform debugging in development environment or in the testing environment but not in the production environment.

Types of assert statements:

1.   Simple version

2.   Augmented version

Simple version:

Assert conditional expression

Augmented version:

Assert conditional expression, any message

Example: assert addition(4,2)==6,"Addition of two number=6"

Handling the AssertionError :

#example program on handling the assertion Error

def avg(marks):

    try:

        assert len(marks)!=0

        return sum(marks)/len(marks)

    except AssertionError:

        print("Marks are empty")

stud1=[]

print("Average of stud1",avg(stud1))

stud2=[60,88,70,90]

print("Average of stud1",avg(stud2))

len() is a predefined function in python, It is used to find the length of the given string,array,list,tuple, dictionary,..etc. The number of elements stored in the list, it displays.

What is the difference between Exception handling and assertions?

Assertion is used to alert or warning to the programmer to resolve the development bugs/issues. Where as exception handling is used to handle runtime errors.

Related Video: https://youtu.be/UORaySj-M2w
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