rspotify VS cbindgen

Apologies for the stupid question but I'm fairly new to Rust and can't figure out for the life of me how to use the rspotify crate. As far as I can get with the documentation / examples is just that it isn't a regular application / binary of itself but just a crate, but I don't see why that's causing me issues. Whenever I try to run the following example, I get the following error, despite me trying to remove and rebuild the crate just in case.

Link to the example code (Line 42)

I have wanted async generics myself for some time now. In RSpotify, we have both async and blocking users, so we had to resort to maybe_async to switch between them. However, this macro has a few caveats and isn't as convenient as having it built-in.

maybe_async accomplishes this by switching based on the feature flags enabled for your library. I found it in rspotify, but haven't actually given it a try myself.

As a developer of rspotify I'm curious as to why you chose not to use an already existing API client for Spotify. Are there any problems you found? I do agree that the current version is a mess but we're working on a full rewrite for 0.10 and you might be interested in that.

Golang uses cgo to communicate with external C libraries and Rust uses FFI (Foreign function interfaces) to export C functions. Additionally, a library for automatically generating bindings can be used to generate the header files (.h). In our case, we'll only be exporting two C functions, so using cbindgen is overkill but we'll use it regardless because why not?  Firstly, we'll write the rust functions we want to export. We'll start by creating a new rust library:

[1]: https://github.com/mozilla/cbindgen

As a 2-step approach, you could also probably use https://github.com/mozilla/cbindgen and then Nim's native C FFI.

The tooling for the first kind -- calling Rust from another language -- is a bit less developed, and tends to rely on code generation that doesn't necessarily produce a natural C API. cbindgen, uniffi, cxx, and Diplomat all take this course.

There's also cbindgen for automating the generation of C headers once you've got your code in the right shape and you'll also want to read the Rustonomicon.

You can backport Rust standard library to C using https://github.com/eqrion/cbindgen .

Later we'll see what cbindgen essentially does is receive a configuration and a Rust library and then spit out a C header (.h) file. One might think that what cbindgen is doing might not be that special and can be done by hand. In which some cases that might be true if the project is simple enough. Though additionally as the cbindgen documentation states:

Fuck it, I'll take the bait. Rust allows for amazing C interop by allowing for exporting of C types as a dynamic library, like C. Unlike C, this still allows for Rust's advanced checking at compile time. librsvg is one such library that is being used in the GTK ecosystem that is also almost completely Rust. You can use tools like cbindgen to generate C bindings.

Or alternatively cbindgen to create the header file from the Rust source.

The easiest way to obtain the headers for the rust code is to use the cbingen library.