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Comment by Lev1a | Hacker News Reader

The whole "Do you have the dependencies and a Python env installed? Noß Then you can't run this script/program." was one of the main reasons I switched from Python to Rust, where cargo as the (very good) package manager comes with the language and, because Rust is a compiled language, you build all the dependencies into your executable you aren't dependent(heh.) on the user having installed a runtime that maybe or maybe not has all the dependencies at the required versions.

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Indeed, Rust + Cargo and Haskell + Stack are very similar in this regard. Both have great package managers, and both produce a shippable executable with only a few dependencies on system libraries. One notable difference is that Stack downloads the compiler, whereas for Rust, every version of the language comes with a compiler and a Cargo. This ensures that you can check out a year-old commit and still build your project with Stack (modulo breaking changes in Stack, which so far I have not encountered), whereas for Rust the compiler version is not pinned.

> for Rust the compiler version is not pinned

Oh, you just need another layer of abstraction! Install rustup, and then (from memory, might be slightly wrong):

  rustup install 1.15.1
  rustup run 1.15.1 cargo build

rustup will take care of getting hold of the right versions of cargo and rustc, and then use them to run the build. I admit that it's not as nice as having the build tool download the right version of everything, but it does work, and you could hide this inside a pretty small shell script or function if you wanted it to be neater.

I have pygradle generate a PEX file for all of my command scripts. Not as seamless as cargo or stack, but it works without rewriting everything.

I should probably have clarified that I wanted the "seamless" way of making the final executable. IIRC, I tried(really hard) and failed on getting some method of "freezing" for Python to work, which made me weary of the prospect of trying something like that in Python in the future(now past).

pyinstaller works great. No issues whatsoever and I'm happily deploying Python 3.6 to machines as far back as RHEL 5.

Single binary to deploy, no dependencies except libc, life is great.

I guess this is true if you don't need to interact with any system libraries.

Could you give an example of what "system libraries" would pose a problem in my example of using Rust with cargo?

Also note that by "no runtime installed" I mean no runtime as in "no Python runtime", "no JVM" etc. not necessarily "no libc"

EDIT: formatting

>Could you give an example of what "system libraries" would pose a problem in my example of using Rust with cargo?

Specifically things like xorg libs, libmpeg, libsdl, and such. Not that Rust would have a problem interfacing with them, just that they would need to be present regardless of whether or not someone was just trying to run a distributed binary.

Agreed that you wouldn't need a VM like CPython or the JVM. However, Rust isn't unique in that department. Almost all languages that compile to binary executables have this advantage.

> Specifically things like xorg libs, libmpeg, libsdl, and such. Not that Rust would have a problem interfacing with them, just that they would need to be present regardless of whether or not someone was just trying to run a distributed binary.

That's why stuff like that is AFAIK usually either distributed with the binary or is absolutely required to have present on the system, regardless of the PL, if you want to/can only distribute a "naked" binary.

> Agreed that you wouldn't need a VM like CPython or the JVM. However, Rust isn't unique in that department. Almost all languages that compile to binary executables have this advantage.

Didn't mean to suggest this is unique to Rust, which is why I wrote

> because Rust is a compiled language.

EDIT: formatting

I think I may have misunderstood your point after re-reading.

I thought you were implying that compiled binaries do not have dependencies. Now I can see that is not the case.

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