Re: [boost] [system][filesystem v3] Question abouterror_code arguments

Subject: Re: [boost] [system][filesystem v3] Question abouterror_code arguments
From: David Bergman (David.Bergman_at_[hidden])
Date: 2009-10-27 13:49:45

On Oct 27, 2009, at 1:43 PM, Andrey Semashev wrote:

> David Bergman wrote:
>> On Oct 27, 2009, at 12:50 PM, Peter Foelsche wrote:
>>>> Others noted embedded environments -- very important today -- but  
>>>> let's look at a broader case.
>>>
>>> I was talking about C++.
>>> C++ includes exception handling.
>>> C++ without exception handling does not make any sense,
>>> as one cannot perform a fallible resource allocation inside a  
>>> constructor.
>> There is no official recommendation for the language in-between EC+ 
>> + and C++ - C++ minus exception handling - AFAIK, but it is no  
>> secret that Boost is targeting that "language" as well, and also C+ 
>> +/CLI to some extent.
>> Strange as it might seem, quite sensical programs have been created  
>> in this unnamed language, even though one cannot use the sometimes  
>> nifty feature of throwing in a constructor. So, I fail to see how  
>> it "does not make any sense."
>
> I don't want to comment the ASIO-related argument, neither I want to  
> convert anyone to anything.
>
> What I want to point out is that IMO, exceptions are sometimes  
> undeservedly ignored for different reasons. One of such reasons is  
> developer's commons, if he got used to code without exceptions and/ 
> or cannot use them properly for the lack of knowledge. Another  
> reason is attempt to achieve overzealous portability, be that  
> ancient buggy compilers from the dawn of C++ or some exotic  
> platforms without exceptions support. All these reasons are valid,  
> at least for now.
>
> But for how long? Developers eventually learn things or move to  
> other languages (C?). Ancient compilers die, new ones become more  
> popular and more efficient. Exotic platforms also either tend to  
> decease or evolve. In my mind, error handling through exceptions  
> should become more preferred over time. Expressing and honoring this  
> tendency in the Standard for the coming 5 years may not be such a  
> bad idea after all.

I agree with all you said, but (i) one should understand the *current*  
need for exception-less solutions and (ii) the idea that (C++) code  
without exception constructs is in some sense nonsensical is, well,  
nonsensical ;-) - all this while striving for exception handling  
everywhere possible and try to push compiler writers to make such  
handling even more efficient.

/David