The Right Approach to Exceptions

Jacob Carlborg doob at
Mon Feb 20 12:18:33 PST 2012

On 2012-02-20 18:05, foobar wrote:
> On Monday, 20 February 2012 at 16:37:28 UTC, Andrei Alexandrescu wrote:
>> On 2/20/12 10:16 AM, Nick Sabalausky wrote:
>>> "Andrei Alexandrescu"<SeeWebsiteForEmail at> wrote in message
>>> news:jhtq31$u8q$1 at
>>>> Again, I think this thread clarified we need the "Variant[string]
>>>> info;"
>>>> member however we define the hierarchy.
>>> I disagree. I don't see a need for that.
>> How would we address custom formatting of e.g. error messages?
>> Andrei
> Separation of concerns - exceptions are meant to notify the *developer*
> of errors. User facing error messages is a separate concern that
> exceptions should not be responsible for. it's not just outsourcing the
> translation strings, it's the developer's job to determine what if at
> all should be done with the exception.
> Trivial example: My mom enters a misspelled URL (e.g. in her
> browser, she does not know or care what 404 means. instead she gets a
> formated page suggesting her to check her spelling and probably a
> suggestion to try instead.
> the exception notifies the developer of the error, the developer does
> extra processing (e.g. to suggest similar valid websites) and the user
> get a friendly notification. clearly it doesn't make sense to put all
> this into the exception.

I completely agree, that's exactly how it should be done. I can't 
understand how difficult it seems to not see this.

/Jacob Carlborg

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