Response to John Carmack saying "writing Rust code feels very wholesome". /u/BobFloss
If you code in rust, you know what he means.
It's an overwhelming feeling of completeness pouring out of your being through your brainwaves and into the global human consciousness, causing a positive net shift and reducing human suffering globally. This newly generated positive energy's existence is only possible from bringing order to chaos and reducing the entropy of the universe, increasing the time for all conscious beings to experience it in all of its beauty before its eventual heat death. Only the truest programmers who take the rust pill and follow its guidance will know this feeling: the feeling of mastering your physical domain to the point where you can wrangle with its fundamental laws at the just the right macroscopic scale that allows for you to achieve the exact results you want in the least time, efficiently using as much of your conscious effort as possible without going past the breaking point. I never could have written a comment like this until programming in rust... Since then I've been a more creative, intelligent, more enjoyable person to be around and it's all thanks to rust. I've even begun borrow checking my own thoughts now and have a much safer thought process because of it, as well as a deeper intuitive understanding of what exactly the creation of thoughts is in the mind.
They forgot the part where they were euphoric, not because of the approval of any thought leader, but because they were enlightened by their own intelligence.
Say the same thing about seatbelts in a car. If you don’t plan to have accidents, why do you need seatbelts?
Car accidents, like mistakes in programming are a risk that has a likelihood that is non-zero. A seatbelt might be a little bit annoying when things go well, but much less so when they don’t. Rust is there to stop you in most cases when you try to accidentally shot yourself into the leg, unless you deliberately without knowing what you are doing while yelling “hold my beer” (unsafe). And contrary to popular belief even in unsafe blocks many of Rust’s safety guarantees hold, just not all.
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Just like with the seatbelt, there will be always those that don’t wear one for their very subjective reasons (e.g. because of edge cases where a seatbelt could trap you in a burning car, or because it is not cool, or because they hate the feeling and think accidents only happen to people who can’t drive).
This one aptly summarizes just how much our consolidation work has paid off!
.. the experience I had in 2019 was dramatically better than the first time I touched the language. After a month I'm feeling very comfortable, and looking forward to writing more.
Can you eli5 why TryFrom and TryInto matters, and why it's been stuck for so long ? (the RFC seems to be 3 years old)
If you stabilise Try{From,Into}, you also want implementations of the types in std. So you want things like impl TryFrom<u8> for u16. But that requires an error type, and that was (I believe) the problem.
u8 to u16cannot fail, so you want the error type to be !. Except using ! as a type isn't stable yet. So use a placeholder enum! But that means that once !is stabilised, we've got this Infallible type kicking around that is redundant. So change it? But that would be breaking. So make the two isomorphic? Woah, woah, hold on there, this is starting to get crazy...
*new person bursts into the room* "Hey, should ! automatically implement all traits, or not?"
"Yes!" "No!" "Yes, and so should all variant-less enums!"
Everyone in the room is shouting, and the curtains spontaneously catching fire. In the corner, the person who proposed Try{From,Into} sits, sobbing. It was supposed to all be so simple... but this damn ! thing is just ruining everything.
... That's not what happened, but it's more entertaining than just saying "many people were unsure exactly what to do about the ! situation, which turned out to be more complicated than expected".
-- Rust's ownership is difficult.
-- Yes, ownership is difficult. For such a difficult thing, you (are going to) ever check by hand rather than having machine do it for you.
"all the ergonomic improvements in rust 2018 are really messing up my book that consists entirely of running face-first into compiler errors so i can explain concepts." -- Alexis Beingessner, author of "Learning Rust With Entirely Too Many Linked Lists"
One major difference is that Ada was created at a time when most military computers were single-core with in-order sequential execution and no cache. Although limited SIMD existed, any other concurrency was very coarse-grained. That’s the underlying execution model for C, Pascal, C++, etc.
Rust was created to address the complexity of multi-core processors with multi-level cache hierarchies where computational efficiency may require much concurrency. In my experience few humans are capable of error-free design and implementation of highly-concurrent systems unless they employ tooling that flags their errors in conceptualization or implementation.
Yes, this adds to Rust’s “wierdness budget”, but this is doing it for the right reason: discovering a way to solve a problem that many programming languages have, but few have really tackled.