jules's comments

On: The EdTech Revolution Has Failed

[jules]

In primary school there was a teacher who straight up hated me because I did the exercises too fast and this would cause extra work for him to keep me busy.

On: my-new-rust-binary-search

[jules]

The modifications that this article makes to the original version [1,2] are not a good idea. The modified version in this article cannot properly be used to search an array, for example (due to the extra "sanity checks", which would cause out-of-bounds errors). The API is also made more complex, returning a pair of options of indices rather than a pair of indices. You really just want the pair of indices!

If you do sanity checks in Rust then you should panic instead of returning options. However, in this case you cannot do the sanity checks, because the contract of the function is that it will only call the predicate strictly between l and r (i.e., only on indices returned by mid). Further, given the initial sanity checks, the sanity checks inside the loop body are redundant, as the loop invariant ensures that those checks never fail.

[1] https://julesjacobs.com/notes/binarysearch/binarysearch.pdf [2] https://byorgey.wordpress.com/2023/01/01/competitive-program...

Here is a Rust implementation of the original:

  pub fn search<T: Mid, G>(predicate: G, mut l: T, mut r: T) -> (T, T)
    where G: Fn(&T) -> bool
  {
    loop {
      match l.mid(&r) {
        None => return (l, r),
        Some(m) => {
          if predicate(&m) { r = m } 
          else { l = m }
        }
      }
    }
  }

Or, traitless:

  pub fn search<T, H, G>(mid: H, predicate: G, mut l: T, mut r: T) -> (T, T)
    where H: Fn(&T,&T) -> Option<T>, G: Fn(&T) -> bool
  {
    loop {
      match mid(&l, &r) {
        None => return (l, r),
        Some(m) => {
          if predicate(&m) { r = m } 
          else { l = m }
        }
      }
    }
  }

On: Structured Outputs in the API

[jules]

Earley parsers should not need more than O(n^2) memory.

On: No More Blue Fridays

[jules]

The eBPF termination checker is buggy anyway; you cannot rely on it.

On: ARC Prize – a $1M+ competition towards open AGI pr...

[jules]

Do computers need 10,000 examples to distinguish dogs from cats when pretrained on other tasks?

[curious_cat_163 → jules]

No.

On: Show HN: I created this land use visualisation for...

[jules]

From reading the description, perhaps "urban greenery" would be a better term than "urban grass".

On: Sam and Greg's response to OpenAI Safety researche...

[jules]

> Any one noticed how Sam sometimes intentionally tries to attack his own work? For example, he has said GPT-2 was very bad, GPT-3 was bad, and GPT-4 is okay. He also fed the AI doomers by talking about AGI dangers and how the world needs to watch out for a future AI catastrophe.

That is the opposite of criticism. It all translates to "GPT-(n+1) is going to be super awesome".

[nicce → jules]

To keep the value of the company increasing and make goverment think that AI should be closed source and controlled by some limited entity for maximum profit.

On: Bend: a high-level language that runs on GPUs (via...

[jules]

Not criticizing new projects is a good social norm, because starting new and ambitious projects is good and should not be discouraged. However, criticizing projects that make misleading, unsubstantiated or false claims is also a good social norm, because it discourages people from making misleading, unsubstantiated or false claims.

On: So We've Got a Memory Leak

[jules]

The article in question is about Ruby, which is garbage collected.

It's easy to get in trouble with an interconnected object graph: you mess up and hold onto a pointer that you shouldn't be holding onto, which results in a leak.

On: Memory safety is necessary, not sufficient

[jules]

While data races may not be a top category empirically, they are undefined behavior, which means that (a future version of) the compiler is allowed to make your program do anything at all after a data race happens. We are setting the bar incredibly low for ourselves if we just accept that things like that happen on the regular.