Exception transparency

[Brian Goetz]

The problem has nothing to do with syntax; the problem has to do with the 
compiler incorrectly assuming a type parameter is variadic.  In the latter 
case "implements List<T>" would not compile!

On 6/8/2010 1:26 AM, "Zdeněk Troníček" wrote:
>
> Brian Goetz napsal(a):
>>> I conjecture that a new syntax may not be needed at the declaration site
>>> at all; it can be inferred from the explicit bound on the type parameter
>>> instead of vice-versa, simplifying the syntax and making it more
>>> familiar.  Specifically, you can treat any type parameter as a throws
>>> type parameter if its bound is Throwable or a subtype.  There is no need
>>> to restrict where the type parameter may be used.
>>
>> I suspect we might regret that.  When you try to write a class like
>>     class ExceptionList<T extends Exception>  implements List<T>  { ... }
>> you'll find that the compiler has guessed your intentions incorrectly.
>>
>
> Could you elaborate on what is wrong with the following code in your opinion?
>
> class ExceptionList<T extends Exception>  implements List<T>  {
>
>      ExceptionList() throws T { ... }
>      ...
> }
>
> In comparison to
>
> class ExceptionList<T extends Exception, throws E>  implements List<T>  {
>
>      ExceptionList() throws E { ... }
>      ...
> }
>
> the former syntax does not seem to be worse.
>
> Z.