Support for export specifiers?

[javamonn]

It appears like workerize-loader only supports moving export declarations in the target module into a worker. I'm attempting to use it with Bucklescript, which compiles modules down to an export specifier list, i.e. export { foo, bar, } instead of export declarations.

I took a pass at implementing this and couldn't get around Webpack declaring its own parser plugin and bailing on export specifier, I think for tree-shaking purposes. I don't have much experience with Webpack plugins though and it seems like there should be a way to get this to work. Are there any alternate approaches you can suggest, or maybe workarounds?

One other thought I had for my purposes would be to instead compile to commonjs and tweak workerize so that it would accept the pre-compiled source instead of doing the current find-and-replace compilation step.

[developit]

Yup, as best I can tell this is a bug in Webpack's parser API :(

FWIW I think it would actually be better to switch from static analysis to having the worker postMessage() up its exported keys on init. This means a breaking version change since it will make worker instantiation asynchronous, but it would add support for reexports and export declarations.

[jamesknelson]

This would be really handy, as rollup also exports things via export specifiers -- so any module that is built with rollup is going to be unusable as a worker as-is :-(

[jamesknelson]

I've managed to solve this issue for my use case with ES6 Proxies. I've published a fork if anybody needs it: https://github.com/jamesknelson/workerize-proxy-loader

[developit]

For passers-by: if anyone has an interest in adding support for CommonJS export parsing, I'd be happy to review and merge a PR for it.