Rather simple question.
Where should I store error,exception, user messages?
By far, I always declared local strings inside the function where it is going to be invoked and did not bother.
e.g.

```
SomeClass::function1(...)
{
std::string str1("message1");
std::string str2("message2");
std::string str3("message3");
...
// some code
...
}

```

Suddenly I realized that since construction & initialization are called each time and it might be quite expensive. Would it be better to store them as static strings in class or even in a separate module?
Localization is not the case here.

Thanks in advance.