Unit 8 Logic and Languages (2.3 Producing Robust Programs)

Creating programs that can handle unexpected or erroneous data and/or inputs by anticipating misuse.

they will try to: * use input validation & authentication * anticipate how users might misuse their program, then attempt to prevent this * ensure their code is well maintained * reduce the number of errors in the code throught testing

designing a system, predicting how users can act in an unintended or malicious way and minimising this

the process of determining the identity of a user

the process of checking that the data entered by a user is appropriate for its use, so that it can be correctly processed without any errors

• presence check • range check • length check

checks that data has been entered and not blank.

checks that an input falls within the required range.

checks a specified number of characters have been entered.

name = input(“Enter your name”) if name == “”: print(“Invalid”)

num = int(input(“Enter a number less than 10”)) if num >= 10: print(“Too large!”)

password = input(“Enter a password, minimum 8 characters.”) if len(password) < 8: print(“Password too short!”)

• sub programs • naming conventions • indentation • commenting