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No you don't, you're massively exaggerating. The standard library already has at least basic if not strong exception-safety all over it. And RAII is pretty darn standard practice and guarantees basic exception safety in your own code too. You don't need strong exception safety here, just basic is sufficient for most such cases.

Go try this with std::sort (or std::adjacent_find or whatever) and tell me which of their implementations you had to modify.

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Well but of course! These functions are already implemented with basic exception safety in mind. What if they weren't? This is exactly the same situation as a function that has

    callback();

which cannot be changed into

    if Err(error) = callback() {
        return error;
    }

because that would break some invariants.

Changing return type from "void" into some "result" is a mechanical change.

As I already explained: RAII is pretty darn standard practice and guarantees basic exception safety in your own code too. The music is already there and people are already dancing to it.

> What if they weren't?

Obviously the language wasn't designed for rebels. The implicit understanding with tools is that you use them the way they're meant to be used. Only in that case do you get to assume you'll reap the benefits they claim to provide. If you insist on deliberately dancing to a different tune, then you get exactly what you asked for. You can't drive against traffic and then complain people run into you.

There are interesting non-rebel cases of What if they weren't. I have a library (object only, no source) written for C (not C++) which wants callbacks. It is the only interface provided by the vendor for something that shall remain nameless. Every callback has to be wrapped in a try catch, or hell will break loose.

> Changing return type from "void" into some "result" is a mechanical change.

.. but then checking the returned val for error in every call sites is very far from mechanical change. (Attribute about unused return result can help here, with obvious drawbacks.)

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