Contracts and Assertions
- slide 20 : 32
Everyday invariants
Adherence to invariants is the key to order in our daily lives
Coffee Machine
In between operations there is always at least one cup of coffee available
Toilet
In between "transactions" there is always at least 0.75 meter of toilet paper on the roll
Keys and wallet
In between using keys and/or wallet
During daytime: Keys and wallet are in the pocket
During nighttime: Keys are wallet are located on the bedside table or underneath the pillow