Exceptions

[joto]

Currently std::runtime_exception is thrown in a few cases. Should we have our own exception type?.

In the case of get<wrong_type>() P0088R0 uses bad_variant_access derived from logic_error for this.

[springmeyer]

👍 to custom exception type if you see a benefit (as long as it inherits from std::exception of course).

[joto]

A custom exception type would allow a user to differentiate between an exception thrown by our variant type and an exception that is somehow propagated from a type wrapped in the variant. I am not sure this is strictly necessary, but it would be cleaner in any case.
Before I change this: Is there any code checking for this exception somewhere? @artemp ?

[artemp]

@joto - sounds good re: custom exception.
Lets derive it from std::exception so existing code will continue to work or at least it'll be easy to fix.

[joto]

I have create a new class bad_variant_access now derived from std::runtime_error and use this in the get<T>() functions. This is backwards-compatible. User code using this should switch to the new type and then we can later on switch the parent class to the more correct std::logic_error as in the upcoming standard.

[artemp]

closing as this issue moved to #95