The Right Approach to Exceptions

[deadalnix]

Le 20/02/2012 20:12, Nick Sabalausky a écrit :
> "Andrei Alexandrescu"<SeeWebsiteForEmail at erdani.org>  wrote in message
> news:jhtss8$12mq$3 at digitalmars.com...
>> On 2/20/12 10:16 AM, Nick Sabalausky wrote:
>>> "Andrei Alexandrescu"<SeeWebsiteForEmail at erdani.org>   wrote in message
>>> news:jhtq31$u8q$1 at digitalmars.com...
>>>>
>>>> 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?
>>
>
> Maybe I've misunderstood your intent for this "Variant[string] info;" My
> understanding is that, for example, you want to replace this:
>
> ----------------------------------------------------
> class Exception {}
> class FooException
> {
>      string fooName;
>      int fooID;
>      bool didBarOccur;
>
>      this(string fooName, int fooID, bool didBarOccur)
>      {
>          this.fooName = fooName;
>          this.fooID= fooID;
>          this.didBarOccur= didBarOccur;
>      }
> }
> ----------------------------------------------------
>
> With this:
>
> ----------------------------------------------------
> class Exception
> {
>      Variant[string] info;
> }
> class FooException
> {
>      string fooName;
>      int fooID;
>      bool didBarOccur;
>
>      this(string fooName, int fooID, bool didBarOccur)
>      {
>          this.fooName = fooName;
>          this.fooID= fooID;
>          this.didBarOccur= didBarOccur;
>
>          info["fooName"] = fooName;
>          info["fooID"] = fooID;
>          info["didBarOccur"] = didBarOccur;
>      }
> }
> ----------------------------------------------------
>
> If so, then I don't see any usefulness of "Variant[string] info" other than
> to start treating exceptions like JS's abomination of an "object" (Or at
> least AS2's objects anyway - not 100% certain how much of AS2 is taken from
> JS). If not, then could you clarify what you meant?
>
> In either case, I am interested to hear in more detail how you see
> "Variant[string] info" being used to address i18n. I haven't really dealt
> with a lot of i18n myself.
>
>

Why not use tupleof on the Exception instead of Variant[string] ?