The Right Approach to Exceptions

[Andrei Alexandrescu]

On 2/21/12 2:42 PM, Jacob Carlborg wrote:
> On 2012-02-21 21:27, Andrei Alexandrescu wrote:
>> On 2/21/12 2:26 PM, Jacob Carlborg wrote:
>>> As I said, it seems you want to push up implementation details specific
>>> to a given subclass to the base class even though it shouldn't be pushed
>>> up.
>>
>> I explained that doing so allows for proper formatting of error
>> messages. So it should pushed up.
>>
>> Andrei
>
> Well, I don't think that is the right approach. As many others have
> explained, error messages are only a small part of exception handling.

I agree. Also, one interface function is only a small part of a class 
hierarchy.

> If you do want to have a generic way of getting an error message out of
> an exception, what's wrong with toString? Or a new method that formats
> the error messages. No need to push up the instance variables to the
> base class.

This has been answered in the long thread. In brief, toString loses too 
much information and putting formatting inside exceptions is not the 
right place.


Andrei