ID	FCNS-16
Title	Use nested functions sparingly/only when really beneficial.
Priority	Strongly recommended
Severity level	5
Description	Use nested functions sparingly/only when really beneficial.
Rationale	Nested functions reduce the readability and robustness of the code and can not be tested independently.
Exception	Because variables can be shared, nested functions can be useful to prevent a massive interface with a lot of inputs and outputs.