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Comment by swsieber | Hacker News Reader

> The advantage of a standard library is that you only need to learn one API instead of a dozen different APIs for doing the same thing, which means you can develop a degree of mastery over it.

The rust ecosystem has done well to converge on certain crates as sort of replacement for missing std features.

In practice (at least in the rust ecosystem), I only need to learn one interface for:

* regex (regex)

* serialization (serde)

* network requests (request)

There are de-facto base crates in the ecosystem.

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As a relative outsider, it’s not obvious at all that these are the right crates to choose. I appreciate the commitment to long-term stability that the standard library appears to have, but that benefit goes out the window if I accidentally rely on a third-party crate that changes its API every six months.

Looking at crates.io, regex looks pretty safe, as it’s authored by “The Rust Project Developers” and includes explicit future compatibility policies. Unfortunately, I can’t find an index of only the crates maintained by the Rust team.

Serde is obviously popular, but at first glance is a giant Swiss Army knife that will likely have lots of updates to keep track of that are completely unrelated to my project (whatever it is). If I search for JSON, I get an exact match result of the json crate, followed by a bunch of serde-adjacent crates, but not serde itself.

Request hasn’t been updated in 4 years, and has a total of less than 7000 downloads.

That sounds like something that could be solved by having crates.io provide a curated list of common popular crates for certain features. That is, this seems to be mostly a documentation issue.

It’s really a reputation bootstrapping problem, for which popularity can be a useful proxy. For me to use third-party code, I have to trust that the future behavior of the developers will be reasonable: I want my side projects that don’t get touched for months or years to still mostly work when I get back around to them.

Not everyone or every project will have the same desires, though. Sometimes, a fast-moving experimental library is the right choice. The trouble is figuring out which I’m looking at.

I'm not sure I follow these concerns about "working in the future" - as long as you specify versions that work for you in your Cargo.toml file, that should work at any point in the future given that you use Rust 1.x.

If you'll want to update to always be on the latest version of each crate, well that discomfort about them potentially not working is part of the price.

If I come back to something, it’s because I want to resume active development. Keeping a dependency pinned at an old version makes that more difficult in various ways, so I personally value forward compatibility.

Not everyone does, and that’s fine. I just want to know what a library developer’s stance on it is before I try to use their library.

This was attempted by the Libz Blitz back in 2017. See the rust-cookbook: https://rust-lang-nursery.github.io/rust-cookbook/ .

I agree that this should be better documented and probably more integrated with crates.io somehow.

Anyone can search for "awesome [lang]" when they want such a thing.

Because it's "reqwest", not "request".

All these libraries are very well known within the community and are what I would come up with as a complete outsider (I don't think I've written more than a hundred lines of Rust code to this date).

You can also find some pointers here:

https://github.com/rust-unofficial/awesome-rust

https://lib.rs

There's actually a more official resource: the rust cookbook[0]. This is maintained by the rust-lang team (rust-lang-nursery is an official place for crates maintained by the rust language maintainers).

[0]: https://rust-lang-nursery.github.io/rust-cookbook/

They probably meant reqwest (https://github.com/seanmonstar/reqwest), not request. Reqwest is maintained by the same developer (seanmonstar) as hyper, the de facto standard http library.

Ah, I did. I posted that on my phone. Autocorrect strikes again.

Do they also compile and run across all platforms supported by rust compiler?

Because that is the biggest asset from stuff being in the standard library.

No, but not all parts of std run on all supported platforms.

To clarify, there are different levels of support on different platforms.

Then it already starts with a failure of quality gate of what goes into std.

Not really. Rust supports 8 bit microcontrollers. Lot's of libraries, including parts of the standard library make no sense on these kind of platforms.

The standard library and 3rd party crates generally have excellent compatibility across mainstream platforms.

So do Basic, Ada, Pascal, C and C++ as well, and yet they have richer standard libraries, with deployment profiles.

Since when does libc include "rich" things like regex, serialization and http?? Even C++ standard lib is mostly containers and algorithms.

libc is barely a standard library, it's almost nothing.

C might not include those specific examples, but POSIX + libc already include plenty of stuff.

C++ surely does include regex, with serialisation and http scheduled for C++23, or with luck with a TR as intermediate delivery.

Although serialisation depends on static reflection being finalized as well.

Still, it implies C fails, because you don't get POSIX on all available platforms.

I think the definition is meaningless. Rust spends huge amount of resources to test itself and its surrounding ecosystem on tier 1 platforms.

I'm fairly certain regex from c++ std will run like crap, if at all on something with 4MB of RAM.

Except the small detail that C's POSIX support is much wider than Rust's tier 1 platforms.

I am fairly certain that without profiling and defining a test configuration for a set of specific C++ compilers / standard C++ library I won't assert anything about std::regex performance with 4 MB of RAM.

Perhaps. But you're comparing a 26 year old standard for a 47 year old language, to a language that's been stable for 4 years.

>deployment profiles

In other words, not all functions in the stdlib of Ada, Pascal, C and C++ can be used in all possible target environments? Sounds like a failure to quality gate those standard libraries.

Nice jab try there, the suble point you are missing is that a deployment profile still is a guarantee of support.

There aren't an endless number of profiles.

I'm not sure if you're just being disingenuous here, but you're right that you're not going to be able to use all functionality from the stdlib of Ada ( and others ) on every possible target, but you were never, ever going to. And Rust certainly won't solve this problem for you. It's not a consequence of poor standard library design either. It might not be immediately obvious, but even C has a runtime library, which needs to be specific to the architecture and OS that you're targeting. Just for a quick example, `malloc` is going to need to function differently depending on what OS you're running, and if you're targeting a microcontroller with extremely limited RAM it might not even need to be implemented at all.

I don't think the parent was claiming the Rust was better in this regard, just that it was no worse. Other languages also restrict standard library features on some platforms.

Not exactly. Rust can be made to run on 16-bit toaster or even OsIJustWrote. Just because it can be run, doesn't mean Rust std lib devs will support 16-bit toasters or OsIJustWrote.

Each platform has different levels of support. Primary being Windows, Mac and Linux, where every pure Rust crate runs.

Std lib makes certain reasonable assumptions, for which it works e.g. malloc exists and panic! is implenented.

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