Past Meetup

ACCU York [Jan 2019] - Option(al) Is Not A Failure

This Meetup is past

13 people went

Department of Computer Science, University of York

Deramore Lane, University of York, Heslington, York, YO10 5GH · York

How to find us

Meeting in CSE/082, people will be around to let you into the building

Location image of event venue


We have the honor to welcome Phil Nash to ACCU York. Phil is the author of the C++ test framework, Catch2 and command line parser Clara. As Developer Advocate at JetBrains he's involved with CLion, AppCode and ReSharper C++. More generally he's an advocate for good testing practices, TDD and using the type system and functional techniques to reduce complexity and increase correctness. He's previously worked in Finance and Mobile as well as an independent consultant and coach specialising in TDD on iOS.

Abstract: Error code returns were bad so we invented exceptions. Much better we said. Then we realised exceptions had their problems - with 52% of a recent ISO survey's respondents saying they were banned on all or part of their codebases! We've been trying to patch them up how we can (with noexcept, for example) - but most of the problems are systemic.

So there's been a return to error codes. But now we have new features in the language (arithmetic data types, including variant and optional) - and the promise of more coming (expected, outcome?) - that bring us closer to the best of both worlds - although, perhaps, with different compromises.

But there's more. Where do error_code and error_condition fit in? What's all this about monadic binding? A try keyword? What do other languages that are further down this road do and what can we learn from them?

This talk will be a tour of the past, present, and possible future of C++ error handling; the trade-offs and rationale for each piece and a discussion of where to go next and what we can do as a community to get there. We'll look at a number of in-flight proposals, and include up-to-the-minute status on them following the most recent standards meeting.