Thoughts on Rust, a few thousand lines in
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Re: Thoughts on Rust, a few thousand lines in
#2> the escape hatch suggested on the internet, `partial_cmp(...).unwrap_or(Ordering::Less)`
This is often a Bad Idea, as you get unstable sorts and you are right back to the same problem.
- Explanation: How do I get the minimum or maximum value of an iterator containing floating point numbers? — https://stackoverflow.com/a/50308360/155423
- Example: https://play.integer32.com/?version=stable&mode=debug&editio...
See also:
- How to do a binary search on a Vec of floats? — https://stackoverflow.com/q/28247990/155423
Instead, use a wrapper type or raise a panic.
Re: Thoughts on Rust, a few thousand lines in
#3> Unlike nearly every language I’ve ever used, Rust actually encourages variable shadowing.
Haskell does it too, for the same reason/purpose / with the same effect.
Re: Thoughts on Rust, a few thousand lines in
#4This makes me want to add `p90`, `p50` and so on to jq...
Re: Thoughts on Rust, a few thousand lines in
#5> Unlike nearly every language I’ve ever used, Rust actually encourages variable shadowing. Haskell does it too, for the same reason/purpose / with the same effect.
Swift does, but typically for Optional promotion. You see stuff like `guard let delegate = delegate else { return }` inside functions all the time, shadowing a property with a local & promoting the type from Optional to T.
It's not the same as the Rust example because you're shadowing an ivar to a local, but since `self.` is implicit you're still shadowing.
Re: Thoughts on Rust, a few thousand lines in
#6This makes me want to add `p90`, `p50` and so on to jq...
for the record, pXX are super useful in splunk.
Re: Thoughts on Rust, a few thousand lines in
#7> Unlike nearly every language I’ve ever used, Rust actually encourages variable shadowing. Haskell does it too, for the same reason/purpose / with the same effect.
Swift does, but typically for Optional promotion. You see stuff like `guard let delegate = delegate else { return }` inside functions all the time, shadowing a property with a local & promoting the type from Optional to T. It's not the same as the Rust example because you're shadowing an ivar to a local, but since `self.` is implicit you're still shadowing.
> for Optional promotion
You'll see the same in Rust
fn example(name: Option) -> Option {
let name = name?;
Some(name.len())
}
fn example(name: Option) {
if let Some(name) = name {
println!("{}", name.len());
}
}
> but since `self.` is implicit
To make sure I'm following, do you mean that Rust's `self.` is implicit in Swift?
Re: Thoughts on Rust, a few thousand lines in
#8Earlier quoted context omitted.
Swift does, but typically for Optional promotion. You see stuff like `guard let delegate = delegate else { return }` inside functions all the time, shadowing a property with a local & promoting the type from Optional to T. It's not the same as the Rust example because you're shadowing an ivar to a local, but since `self.` is implicit you're still shadowing.
> for Optional promotion You'll see the same in Rust fn example(name: Option ) -> Option { let name = name?; Some(name.len()) } Or fn example(name: Option ) { if let Some(name) = name { println!("{}", name.len()); } } A main difference is the requirement to use `Some`, which allows for the flexibility to apply to any enum. > but since `self.` is implicit To make sure I'm following, do you mean that Rust's `self.` is…
Yeah `self.` is implicit. In Swift:
struct S {
var string: String
func doSomething() {
// These two lines are equivalent.
print(string)
print(self.string)
}
}Re: Thoughts on Rust, a few thousand lines in
#9 let foo = "...";
let foo = parse(foo);
let foo = escaped(foo);
I would consider this shadowing (something you can do in OcaML):
let foo = "..." in
let foo = parse(foo) in
let foo = escaped(foo) in
dosomething(foo);;Re: Thoughts on Rust, a few thousand lines in
#10I've not done any rust dev before but the whole variable shadowing thing really scares me, in that it makes it not obvious where the initial declaration comes from. This seems difficult to reason about.