As a C++ developer I've recently been in the midst of the Exceptions debate. Exceptions as a feature of the C++ language have long divided the community, naively I've often put this down to their coming to the language from elsewhere (C perhaps) where exceptions were not the norm.
This was a mistake, for in the projects I've previously worked upon the overhead of an exception compared to the ramifications of the error resulting in a crash have often totally outweighed the overhead, making deciding to employ an exception exceptionally easy (*bum bum*). Exceptions were the norm, still are and should be to you too (according to the C++ Core Guidelines https://github.com/isocpp/CppCoreGuidelines/blob/master/CppCoreGuidelines.md#Ri-except).
The difficulty, the dilemma if you will, comes not from the feature, but the cost. If you application domain demands high performance you can not risk using exceptions, the argument carries on therefore whether in not using them to avoid that overhead in performance you are actually cutting off your nose to spite your face... What are the downstream costs if an unexpected, in tested for, error occurs and some strange behavior ensues, or worse it propagates up and out of your application to crash?!!
In the modern era of social media such feedback is near instantaneous, can you afford the egg on face?
And so you spin yourself around and dig further into the ground your problems.
Voices from industry do little to alleviate the problem, google for instance (https://google.github.io/styleguide/cppguide.html#Exceptions), almost seem to advocate using exceptions if from the ground up you can build them in. You stand the cost of retraining developers and change your ways of working around (e.g. embrace RAII).
They even go so far as to state "the benefits of exceptions outweigh the costs", but then add the caveat "in new projects". How old or new your project should not define your error handling mechanisms, surely? Plus from experience I've always found a code base is as old or new as the minds working upon it. If you have an engineer firmly rooted in C without exceptions they will continue to churn code in that style through your compiler (which will happily work with it), not because it's a better way of working nor because it's a worse way of working, quite often it's continued along simply under the inertia of experience that developer has and they've not time to stop to take stock.
Even given that time, which the project I've just begun working upon has, there's weight behind the past, the old way of working, what worked before, and if that was non-exception handling code people stick with it. Tell those self same people "you really should use these, oh and you have to retrain your minds, plus it'll take longer to compile and more time to run" they're going to stare at you like you're mental.
The question I'm left with is therefore not whether to use exceptions or not (well I am left with this problem, and this post is no help) instead we're left with the question of when will the benefits of exceptions, their ease of use, simplicity to write and visualise out weight the retraining, compile time and runtime costs?... I don't think that's anytime soon, it should be after so many years, but it's simply not.
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