Function 可能是 const 或不是取决于 arguments

Question

I'm trying to refactor some code by facotirising duplicate code. Let's imagine I end up with a class like:

class A {
public:
void method1() 
{
  do_work(true);
}

void method2() const
{
  do_work(false);
}


private:
void do_work(bool flag) {
...
if(flag)
this->data = 0;
}
}

However this won't compile because do_work is not const, even though calling this method with flag = false is const. Is there a way to "fix" this without splitting again the implementations?

Answer 1

do_work is poorly refactored, as a function that is "sometimes const".

Separate out the const and non-const logic.

class A {

  void method1() 
  {
    do_work();
    this->data = 0;
  }

  void method2() const
  {
    do_work();
  }

private:

  void do_work() const {
    ...
  }
}