Calling external javascript functions in clientside callbacks


I’ve been playing around with clientside callbacks today (to hopefully attach to wasm runtime). However, importing external javascript in any of my files in /assets will cause the following error:

Cannot read properties of undefined (reading ‘*’)

where * is the name of the js-defined callback. Is there a possibility to statically (once) import js-functions from other files and call them from the clientside callback function?

My /assets/custom-script.js looks like

import * as external from "./external"

window.dash_clientside = Object.assign({}, window.dash_clientside, {
    clientside: {
        call_greeting: function(name) {
            return external.greet(name);

Dynamic imports almost works though (allowing promised values as of Dash 2.4?)

window.dash_clientside.clientside = {
    call_greeting: function(name) {
        return import("./external").then((module) => {
            return module.greet(name)

However, using such dynamic import, the wasm runtime would somehow be started at each function call, which probably would be excessive?


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