Against enforce()

[Daniel Gibson]

Am 17.03.2011 02:07, schrieb Andrei Alexandrescu:
> On 03/16/2011 06:45 PM, bearophile wrote:
>> - Where it is used it usually doesn't give a more meaningful exception
>> like WrongArgumentException, etc. I don't want a deep hierarchy of one
>> hundred standard exceptions, but I think some standard exceptions for
>> the most common mistakes, like wrong arguments, etc, are better than a
>> generic enforce(), especially for a standard library code that is
>> meant to be written with care and to give better error
>> messages/exceptions.
>
> enforce helps such idioms, does not prevent them. From the docs:
>
> ===============
> T enforce(T)(T value, lazy Throwable ex);
>
> If value is nonzero, returns it. Otherwise, throws ex.
> ===============
>

Really?
using enforce with a custom throwable saves *one* char:
   enforce(foo, new BlaException("bad!"));
   if(!foo) throw new BlaException("bad!");
or are there other merits?

But using enforce with a custom message (thus it'll just throw a 
standard Exception with that message), like assert, really shortens things:
   enforce(..., "bad!");
   if(!...) throw new Exception("bad!");

So of course enforce allows to throw meaningful exceptions, but it 
doesn't make it considerably easier/shorter.

Cheers,
- Daniel