Re: The future of Spark . Spark 2014 : a wreckage

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Thu, 18 Jul 2013 23:32:57 -0500, Randy Brukardt wrote:

>> It won't be any more complex than it is when handling exceptions
>> propagating out of Open. In fact it will be much simpler because you 
>> forgot the issue of closing the file on subsequent errors.
> 
> I've never had the slightest "issue" with closing the file at the end. And 
> certainly, there aren't "subsequent errors", because either the file gets 
> opened eventually, or the whole routine is aborted (usually, the entire 
> program is halted at the point, since failure to be able to write results --  
> no one needs to calculate results if you can't save them).

I meant I/O errors and more elaborated cases like sockets. If you open a
socket file you should bind it, set options which may fail as well. Code
that does not use controlled wrappers look very ugly.

It is *always* a much better design when the object maintains a state
invariant (e.g. file is open). Provability of such code is a nice
byproduct.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de