Import error with unexpected token

• Jun 18, 2025 - 09:28

Hello,

In my current plugin layout, designed to be modular, the main file simplicior.qml lives in a folder simplicior on the plugin search path. At line 27, it pulls in a JavaScript file as:

import "./src/key.js" as Key

and the key.js itself pulls in a symbol from a helper:

import { log } from "./src/helpers.js";

The symbol log is exported from the helpers.js file. Unfortunately, I get the following error:

09:19:28.857 | ERROR | main_thread     | ExtensionBuilder::load | "file:///home/peter/Documents/MuseScore4/Plugins/simplicior/simplicior.qml:27 Script file:///home/peter/Documents/MuseScore4/Plugins/simplicior/src/key.js unavailable\nfile:///home/peter/Documents/MuseScore4/Plugins/simplicior/src/key.js:1 Unexpected token `import'\nfile:///home/peter/Documents/MuseScore4/Plugins/simplicior/src/key.js:1 Unexpected token `string literal'\n"

For some reason a \n made it into the URI with a file scheme. I suspect that the expression should have read:

import file:///home/peter/Documents/MuseScore4/Plugins/simplicior/src/key.js

Note, with a space instead of a \n. Is that a bug or a feature, or are my assumptions on imports wrong?

Kind regards,
peter

Comments

• Jun 18, 2025 - 11:35

Just forgot to mention, problem was observed in MuseScore-Studio-4.5.1.250800846-x86_64.AppImage on Ubuntu 22.04.2 LTS.

To reproduce, on a command shell:

git clone https://github.com/PeterWurmsdobler/musescore
cp -r musescore/simplicior ~/Documents/MuseScore4/Plugins
~/.local/bin/MuseScore-Studio-4.5.1.250800846-x86_64.AppImage -d

Enable plugin, load a score and run the plugin notation/Simplicior Notation

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• Jun 19, 2025 - 10:16

For the records. Through trial and error I think it has become clear that an imported javascript file cannot in turn import another file. I wonder if this limitation to modular software design is intended, comes with the QmlEngine and could be overcome somehow.

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• Jun 25, 2025 - 14:05

Response:

The error suggests that the JavaScript module import syntax (import { log } from "./helpers.js") is not being interpreted correctly in your QML/JS environment. QML's JavaScript engine has limited support for ES6-style module imports—it typically expects traditional Qt.include() or relative path imports without import statements.

Instead of using ES6 imports in key.js, try:

For helper functions: Use Qt.include("helpers.js") and access log as a global symbol.

For modularity: Move shared code to a .pragma library JS file or restructure imports in QML (e.g., import "src" as Helper).

The \n in the error is likely a red herring; the core issue is unsupported import syntax. Check Qt/QML’s documentation for supported JS features in your version.

Let me know if you need further clarification!
https://bazi-lab.com/
https://yt-transcript.com

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