defn- should not be exported

[ghost]

Is your feature request related to a problem? Please describe.

React HMR does not work as reliably when a file exports non-react components. The problem is that Clojure by default exports any non private var, and Squint in particular seems to export any variable (this may be a bug).

Example warning from Vite:

12:03:27 AM [vite] hmr invalidate /src/main.jsx Could not Fast Refresh. Learn more at https://github.com/vitejs/vite-plugin-react/tree/main/packages/plugin-react#consistent-components-exports

Describe the solution you'd like

Only export vars with metadata :export. This would be similar to what shadow-cljs provides for external modules.

[borkdude]

Thanks for the issue. By design squint exports any non-private var, that is intentional.
But you're right that squint also exports private vars, created with defn-. This is something we can fix. Would that be a solution to your problem?

[ghost]

The only drawback is doing def ^:private for any variable.

But perhaps one should be setting up HMR with Clojurescript macros rather than Vite's default React support.

[borkdude]

I can't change the current behavior because the normal behavior of ClojureScript is that you can access vars from other ClojureScript namespaces without adding ^:export.

But fixing defn- would be good in all cases, so let's start with that.

I'm not sure what you mean by HMR with CLJS macros.

[borkdude]

Released in 0.6.89