Code complexity
It is the cyclomatic complexity, also known as McCabe metric. Whenever the control flow of a function splits, the complexity counter gets incremented by one. Each function has a minimum complexity of 1.
Or. A measurement of the intricacy of a program module based on the number of repetitive cycles or loops that are made in the program logic. It is used as a general measure of complexity for software quality control as well as to determine the number of testing procedures. 
Why care?
- How many outcomes for a given piece of code?
- Outcomes create behaviors. Each is a possible regression.
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