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+---- Thread: Rule 10-3-1 (/showthread.php?tid=1018)
Rule 10-3-1 - wcarl - 17-01-2014
There shall be no more than one definition of each virtual function on each path through the inheritance hierarchy.
If I'm interpreting this rule correctly, once you define a virtual function for a derived class with the virtual base class as an ancestor, no more derivations in the chain can override the first definition.
This would seem to cripple a key advantage of using classes and an object-oriented design.
Isn't it pretty common to override a virtual member function in a child class even if the parent class has provided a different definition? Please explain.
Re: Rule 10-3-1 - misra cpp - 05-10-2015
This is intentional and, as stated in the text for the rule, is done to increase clarity for review and maintenance. It would be acceptable to deviate if a more complex hierarchy is required.
We will review this when working on the next version of MISRA C++.
Re: Rule 10-3-1 - dg1980 - 15-11-2017
Under the impression of MISRA Compliance i came up with two deviation permits so far:
- Reliability (Fault tolerance): Implementing default/fallback behaviour/strategy for polymorphic types
- Maintainability (Reusability): Extending base class functionality for polymorphic types
Re: Rule 10-3-1 - misra cpp - 17-01-2018
Thanks