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  • 32 Comments
Joined 1 year ago
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Cake day: June 26th, 2023

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  • For a direct replacement, you might want to consider enums, for something like

    enum Strategy {
        Foo,
        Bar,
    }
    

    That’s going to be a lot more ergonomic than shuffling trait objects around, you can do stuff like:

    fn execute(strategy: Strategy) {
        match strategy {
            Strategy::Foo => { ... }
            Strategy::Bar => { ... }
    }
    

    If you have known set of strategy that isn’t extensible, enums are good. If you want the ability for third party code to add new strategies, the boxed trait object approach works. Consider also the simplest approach of just having functions like this:

    fn execute_foo() { ... }
    fn execute_bar() { ... }
    

    Sometimes, Rust encourages not trying to be too clever, like having get vs get_mut and not trying to abstract over the mutability.






  • I’m too lazy to convert that by hand, but here’s what chatgpt converted that to for SQL, for the sake of discussion:

    SELECT 
        a.id,
        a.artist_name -- or whatever the name column is in the 'artists' table
    FROM artists a
    JOIN albums al ON a.id = al.artist_id
    JOIN nominations n ON al.id = n.album_id -- assuming nominations are for albums
    WHERE al.release_date BETWEEN '1990-01-01' AND '1999-12-31'
    AND n.award = 'MTV' -- assuming there's a column that specifies the award name
    AND n.won = FALSE
    GROUP BY a.id, a.artist_name -- or whatever the name column is in the 'artists' table
    ORDER BY COUNT(DISTINCT n.id) DESC, a.artist_name -- ordering by the number of nominations, then by artist name
    LIMIT 10;
    

    I like Django’s ORM just fine, but that SQL isn’t too bad (it’s also slightly different than your version though, but works fine as an example). I also like PyPika sometimes for building queries when I’m not using Django or SQLAlchemy, and here’s that version:

    q = (
        Query
        .from_(artists)
        .join(albums).on(artists.id == albums.artist_id)
        .join(nominations).on(albums.id == nominations.album_id)
        .select(artists.id, artists.artist_name)  # assuming the column is named artist_name
        .where(albums.release_date.between('1990-01-01', '1999-12-31'))
        .where(nominations.award == 'MTV')
        .where(nominations.won == False)
        .groupby(artists.id, artists.artist_name)
        .orderby(fn.Count(nominations.id).desc(), artists.artist_name)
        .limit(10)
    )
    

    I think PyPika answers your concerns about

    What if one method wants the result of that but only wants the artists’ names, but another one wanted additional or other fields?

    It’s just regular Python code, same as the Django ORM.


  • I’m pretty excited about PRQL. If anything has a shot at replacing SQL, it’s something like this (taken from their FAQ):

    PRQL is open. It’s not designed for a specific database. PRQL will always be fully open-source. There will never be a commercial product.

    There’s a long road ahead of it to get serious about replacing SQL. Many places won’t touch it until there’s an ANSI standard and all that. But something built with those goals in mind actually might just do it.


  • I don’t think you really have a choice TBH. Trying to do something like that sounds like a world of pain, and a bunch of unidiomatic code. If you can’t actually support 4 to 10 languages, maybe you should cut back on which ones you support?

    One interesting thing you could try if you really don’t want to cut back is to try having using an LLM to take your officially supported code and transliterate it to other languages. I haven’t tried it at this scale yet, but LLMs are generally pretty good at tasks like that. I suspect that would work better than whatever templating approach you’ve used before.

    If neither of those approaches works, everything speaks C FFI, and Rust is a modern language that would work well for presenting a C FFI that the other languages can use. You’re probably not hot on the idea of rewriting your Go tests into another language, but I think that’s your only real option then.




  • To do it 100% probably isn’t possible, something something halting problem. However, you’d catch a lot of basic mistakes with proper typing. In your example, the first function should be typed like this: fn third_planet_from_sun() -> Planet, where Planet is an enum. De/serializing it still has the same problem of interpreting an arbitrary string, but at least for deserializing it, you can be loose in what you allow and just lowercase it before matching it to the enum.