Program logic bugs vs input/environmental errors

[Sean Kelly via Digitalmars-d]

On Sunday, 28 September 2014 at 22:00:24 UTC, Walter Bright wrote:
>
> I can't get behind the notion of "reasonably certain". I 
> certainly would not use such techniques in any code that needs 
> to be robust, and we should not be using such cowboy techniques 
> in Phobos nor officially advocate their use.

I think it's a fair stance not to advocate this approach.  But as 
it is I spend a good portion of my time diagnosing bugs in 
production systems based entirely on archived log data, and 
analyzing the potential impact on the system to determine the 
importance of a hot fix.  The industry seems to be moving towards 
lowering the barrier between engineering and production code 
(look at what Netflix has done for example), and some of this 
comes from an isolation model akin to the Erlang approach, but 
the typical case is still that hot fixing code is incredibly 
expensive and so you don't want to do it if it isn't necessary.  
For me, the correct approach may simply be to eschew assert() in 
favor of enforce() in some cases.  But the direction I want to be 
headed is the one you're encouraging.  I simply don't know if 
it's practical from a performance perspective.  This is still 
developing territory.