🚀 go-pugleaf

In a previous artivle, Herb Sutter wrote:

>
> In article <9511120523.14310@mulga.cs.mu.OZ.AU>,
>    fjh@munta.cs.mu.OZ.AU (Fergus Henderson) wrote:
> >herbs@interlog.com (Herb Sutter) writes:
> >>While we're on the subject of exception handling, is there any technical
> >>reason not to have an exception spec on every member function of every
> class?
> >
> >There is at least one technical reason - it won't work with template
> >classes.  Consider, for example, the member functions of the STL
> >collection classes.  What exception specification should they have?
>
> Hmm... good point, but while this is a good argument in the case of collection
> classes, is it necessarily true of all template classes?
>

Why shouldn't templates have exception specified ?  Saying that it depends on
the types used in the template instance seems gibberish to me: you could say
the same for any class that use any other class (eitehr publicly or in its
implementation).

The real problem is exception enforcement: a function without a throw clause
can throw any exception, but then again, maybe not. Thus the compiler cannot
enforce anything on such code. This is true for any class, and each time the
designer must decide if he wish to enforce a particular exception or let the
door open for anything to happen.

The fact that types used in template are unknown and may throw any exception
doesn't change that fact: either you put a catch expression on each usage of
the sub-type, or let the unexpected exception handler do the job or you don't
specify exceptions that can be thrown.
-
the biggest problem with C++ is its popularity.                    dak@cae.ca


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