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   Shriram Krishnamurthi (shriramk@mastodon.social)'s status on Thursday, 16-Nov-2023 01:18:16 JST Shriram Krishnamurthi

   • David Beazley

   Today's @dabeaz example in PL shows why it's essential to understand aliasing (which a lot of people don't!). Apparently Python programmers get pretty confused by the fact that `del b` didn't "do anything", which further confirms this.
   #PyThOnIsEaSy

   • Embed this notice
     Paul Cantrell (inthehands@hachyderm.io)'s status on Thursday, 16-Nov-2023 01:18:15 JST Paul Cantrell

     in reply to

     • David Beazley

     @shriramk
     Strong agree re aliasing. “Shared mutable state” ought to be a concept students learn to spot early in the curriculum.

     It’s true that Python's wording choice here (`del`) makes this •extra• confusing, and that’s unique to Python. (The Swift folks have been working through a closely related problem with the new explicit pointer ownership & lifetime features, and reached a somewhat better place imo: https://github.com/apple/swift-evolution/blob/main/proposals/0366-move-function.md#)

     @dabeaz

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     Paul Cantrell (inthehands@hachyderm.io)'s status on Thursday, 16-Nov-2023 07:02:35 JST Paul Cantrell

     in reply to

     • David Beazley

     @shriramk @dabeaz
     I’d certainly be curious!

     I put aliasing and shared mutable state in the same breath in our 2nd semester course, early and throughout, but I’m not sure how well it truly sticks. I’ve •definitely• seen confusion around this decrease as we got more mindful about teaching it, but the battle continues!

   • Embed this notice
     Shriram Krishnamurthi (shriramk@mastodon.social)'s status on Thursday, 16-Nov-2023 07:02:36 JST Shriram Krishnamurthi

     in reply to

     • Paul Cantrell
     • David Beazley

     @inthehands @dabeaz Nice, thanks! I've been wanting to spend more time studying Swift's notion of ownership, and this clearly plays in with that.

     Think about all the intro programming texts you've read that begin with mutation. Now think how many of them explained aliasing in the context of shared mutable state. (Pretty close to zero, I'm guessing, unless you've written a book…)

     We have a whole tutor to help with this! Want to take a peek?

   • Embed this notice
     Paul Cantrell (inthehands@hachyderm.io)'s status on Thursday, 16-Nov-2023 09:32:54 JST Paul Cantrell

     in reply to

     @shriramk The links appear to require a Brown login…?

   • Embed this notice
     Shriram Krishnamurthi (shriramk@mastodon.social)'s status on Thursday, 16-Nov-2023 09:32:55 JST Shriram Krishnamurthi

     in reply to

     • Paul Cantrell
     • David Beazley

     @inthehands
     Here, take a look at the tutorials linked from here:
     https://cs.brown.edu/courses/csci1730/2023/smol.html
     They're explicitly offered in multiple syntaxes, to show that the underlying ideas are essentially the same. Each tutorial is quite short (5-10 mins max), so you can get a sense of how they play out…

     We've already got several universities using it (and finding problems in their student understanding!). The whole tutor is built entirely around known misconceptions and fixing them.
     @dabeaz

   • Embed this notice
     Paul Cantrell (inthehands@hachyderm.io)'s status on Thursday, 16-Nov-2023 09:34:23 JST Paul Cantrell

     in reply to

     @shriramk Ah, I see, I just have to be logged in to Google, and the brown.edu was a default! Off to poke at it until dinner is on.

   • Embed this notice
     Paul Cantrell (inthehands@hachyderm.io)'s status on Thursday, 16-Nov-2023 09:39:25 JST Paul Cantrell

     in reply to

     @shriramk
     I like the multilingual approach. Do you mechanically generate the three languages from some underlying representation?