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Comment by Udo | Hacker News Reader

There's an API thing from the JS side I don't understand, and I didn't find anything documentation-wise (maybe it's just because I haven't had my coffee yet):

  require('neon-bridge').load()

So this loads... which rs file, exactly? Where do I specify the Rust file to be loaded? Or is there just a single entry point and you're supposed to have one singular Rust module that is named by convention?

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Rust is a compiled language, so the JS files don't directly load a .rs file but instead they load a native Node extension, i.e. a .node file, which is generated by compiling and linking the Rust sources. (The node-cli tooling automates the whole build process.)

The line you cited is automatically locating the .node file, loading it, and returning the module object associated with it.

On IRC a couple people have been questioning this part of the API, suggesting that just using the standard npm module `bindings` might be better. It's a reasonable idea and I'll probably open a discussion in a GitHub issue.

I realize that Rust is a compiled language, that's not the issue. The syntax somehow suggested to me the modules could be compiled on demand, but that is not the issue either.

My question is/was, given two or more modules written in Rust, how do I address and require them by name? Due to its naming I assumed "neon-bridge" would be the glue that handles this. Given the fact that you can require .node files directly, it was not clear to me that "neon-bridge" is just the name of an example module (or is it?).

Ah, I see!

So neon-bridge is a utility npm package I published that automates loading your Neon project (so it's not the name of an example module). And the expectation is that you only have one Rust package ("crate" in Rust parlance) per Node package, which is why you don't need to pass it the name of anything -- it's looking for _the_ native module in the package, as opposed to _a_ native module.

However, that single Rust crate may have multiple modules in its implementation. They live in the src/ directory of your Neon project and are picked up by the Rust compiler and build tool.

And yes, deeeeefinitely need to get some docs going... :P

Cool, thanks for clearing that up. And thanks for working on this, I know with the questions it can sometimes seem like it's not appreciated... :)

Not at all -- my goal is simplicity and clarity so a confused (potential) user is a bug report!

Looks like `neon-bridge`, in this case, is an NPM module.

Yes, it is, but the point is its load() function apparently takes no parameters.

1. https://github.com/dherman/neon-bridge/blob/master/lib/index...

2. https://nodejs.org/api/globals.html#globals_filename

3. https://github.com/dherman/neon-bridge/blob/master/lib/proje...

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