c++ - Good Practice: To Modify Only Function Parameters? -

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say, develop complex application: within object member functions, should modify objects, passed member functions parameters, or can access , modify other objects have access to(say public or static objects)?

technically, know possible modify have access to. asking good practices.

sometimes, bothering pass argument everythying access , modify, if know object member function not used else, me. thanks.

global state never idea (though simpler, example logging), because introduces dependencies not documented in interface , increase coupling between components. therefore, modifying global state (static variables example) should avoided @ costs. note: global constants okay

in c++, have const keyword, document (and have compiler enforce) can modified , cannot.

a const method guarantee visible state of object untouched, argument passed const reference, or value, not touched either.

as long documented, fine... , should strive having few non-const methods in class interface , few non-const parameters in methods.


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