Rahul Gopinath
rahul@gopinath.org
Lecturer at the University of Sydney, Australia. ശ്രീദേവി's Dad. I work in the junction between Software Engineering and Cybersecurity. Interested in Program Analysis, Automatic Repair, Mutation Analysis, Specification Mining, Grammar Based Generators and Parsing.

The recent paper "A Retrospective Study of One Decade of Artifact Evaluations" provides a great empirical basis for reflecting on how we reward and value software engineering research artifacts, such as prototype tools.

#SEResearchers

https://dl.acm.org/doi/10.1145/3540250.3549172

1/

Hi! Do you have thoughts on how your feed should be organized 🤔? We are researchers at the University of Washington exploring end user tools for social media feed curation. We're conducting a study to learn more about the factors users take into consideration when evaluating the saliency of content in their personal feeds. This study will take approx. 30–45 mins and you'll receive a $15 gift card for participation. Learn more and sign up here! https://forms.gle/QcmcaP6tcsAmmUX6A

Let’s try this again. Where you at #fediverse? Boosts welcome so we can get the best sample size.

Each new generation on the web needs to learn that there’s no such thing as a permanent web identity on a commercial web service.

The only long-term solution to maintain your identity is:
1. your own domain name
2. Your own website/blog
3. Several backups

Everything else is temporary. Your accounts on myspace, facebook, medium, twitter, google plus, youtube, tiktok, mastodon will one day disappear or become useless.

You don’t have a "community" on those websites. Only ephemeral discussions.

Hey, friends: If you're still on mastodon.social or mastodon.online, you're about to lose track of weirder.earth, and other servers to follow soon. It's for the safety of our comrades: this is the quieter, kinder part of the fedi where we walk away from instances that can't or don't control harassers.

I know a lot of you still on mastodon.social and .online are newcomers who landed there because so many other instances have closed to new accounts. Please take this time to explore the fediverse and find somewhere with more reliable moderation. The move-instances tool works pretty well these days!

Had my compilers class try to break 133 different compilers, which just wrapped up.

https://types.pl/@dvanhorn/109305895477147646

OK first, this was fun and I recommend it.

The assignment was to write input programs that would be run on the collection of compilers submitted from the *previous* assignment. If results differed from a reference interpreter, that compiler was considered broken. The goal was to break as many things as possible.

The learning objective here was to learn how to read an informal spec and write test cases that are likely to exercise bugs. I think that worked. For many students it was clear they hadn't done this kind of task before and didn't really know where to start, which was surprising to me.

Students very quickly (like in hours) found overspecifications in the behavior of the interpreter and used it to "win", but I was able to adjust the interpreter and after the first day, that kind of exploit went away.

Many students did what I expected: they wrote small tests based on the assignment spec that broke a good chunk of the compilers. With some effort, they could get ~70-80 of the 133 compilers this way.

A few students wrote tests *not* guided by the assignment spec, but instead just wrote small examples drawn from the whole language. They found bugs in the starter code that was given to students, and thereby knocked out all 133 compilers.

One student found a bug in the parser which in two characters broke all the compilers!

Another student found a bug in the run-time system which read some memory as a uint, when it should've been int.

I look forward to refining and iterating on this in the future.

#compilers #pl

HEY HEY FRENZ on mastodon.social! You may want to MOVE to a new instance, very soon.

Why? :sealion:

Mastodon is a bunch of islands that can talk to each other. The smaller and more spread out we are, the easier things are to moderate. Horizontal scaling FTW!

All of you who fled that one site 🐤 ended up at mastodon.social for likely a few reasons. It was obvious, it was big, and it's where you saw a bunch of folks going.

But it has a long history of being poorly moderated, which means a LOT of instances are silencing or blocking it. Which means you're on the big island that SEEMS like it's "where everyone is", but in fact, it's a giant island unto itself (momentarily trending toward turning into a post-bird-site echo chamber), and huge swaths of the Fediverse don't talk to it, or even see it.

If you want the quality of interaction (and moderation!) Mastodon is known for, move thy funky buns to a smaller instance of cool folks you enjoy. :blobcatrainbow:

#feditips #fediverse

/@seresearchers #seresearchers #ComputerScience #grammar

Does anyone know if there a solution to random sampling from an ambiguous context-free grammar without duplication in the derived strings (not the derivation trees)? or is this still an open problem?

/@seresearchers #seresearchers #ComputerScience #softwaretesting #typetheory

For the type theory folks out there, when contrasting between writing unit tests and providing type annotations, is there some thing in type annotations and type checking that correspond to coverage? and more specifically coverage adequacy?