SyntaxError: Missing initializer in const declaration

[aszabonorbert]

Hi,

I'd like to uglify my js scripts with uglifyjs-folder:

npm run uglify

> example@1.0.0 uglify
> uglifyjs-folder assets/js --output all.min.js --pattern "**/*.js,!**/*min.js" --config-file "uglify.json"

but I get the next error:

SyntaxError: Missing initializer in const declaration
    at js_error (/Users/robin/work/docroot/example.com/wp-content/themes/example/node_modules/uglifyjs-folder/node_modules/terser/dist/bundle.min.js:549:11)
    at croak (/Users/robin/work/docroot/example.com/wp-content/themes/example/node_modules/uglifyjs-folder/node_modules/terser/dist/bundle.min.js:1273:9)
    at vardefs (/Users/robin/work/docroot/example.com/wp-content/themes/example/node_modules/uglifyjs-folder/node_modules/terser/dist/bundle.min.js:2286:31)
    at const_ (/Users/robin/work/docroot/example.com/wp-content/themes/example/node_modules/uglifyjs-folder/node_modules/terser/dist/bundle.min.js:2318:27)
    at statement (/Users/robin/work/docroot/example.com/wp-content/themes/example/node_modules/uglifyjs-folder/node_modules/terser/dist/bundle.min.js:1528:28)
    at _embed_tokens_wrapper (/Users/robin/work/docroot/example.com/wp-content/themes/example/node_modules/uglifyjs-folder/node_modules/terser/dist/bundle.min.js:1338:26)
    at block_ (/Users/robin/work/docroot/example.com/wp-content/themes/example/node_modules/uglifyjs-folder/node_modules/terser/dist/bundle.min.js:2177:20)
    at _function_body (/Users/robin/work/docroot/example.com/wp-content/themes/example/node_modules/uglifyjs-folder/node_modules/terser/dist/bundle.min.js:2089:21)
    at arrow_function (/Users/robin/work/docroot/example.com/wp-content/themes/example/node_modules/uglifyjs-folder/node_modules/terser/dist/bundle.min.js:1695:20)
    at expr_atom (/Users/robin/work/docroot/example.com/wp-content/themes/example/node_modules/uglifyjs-folder/node_modules/terser/dist/bundle.min.js:2519:20)

My package.json:

{
  "name": "example",
  "version": "1.0.0",
  "description": "WP theme for example.com",
  "author": "Mr. Example",
  "license": "GPL-2.0-or-later",
  "keywords": [
    "WordPress",
    "Theme"
  ],
  "devDependencies": {
    "autoprefixer": "^10.4.16",
    "jslint": "^0.12.1",
    "minify": "^10.5.2",
    "minify-all-js": "^0.1.9",
    "postcss": "^8.4.32",
    "postcss-cli": "^10.1.0",
    "sass": "^1.69.5",
    "uglifyjs-folder": "^3.3.0"
  },
  "scripts": {
    "watch": "sass assets/scss/style.scss style.css --watch",
    "sass": "sass assets/scss/style.scss style.css --style=compressed",
    "prefix": "postcss style.css --replace --use autoprefixer -b 'defaults' --map",
    "compile": "npm run sass && npm run prefix",
    "uglify": "uglifyjs-folder assets/js --comments --output all.min.js --pattern \"**/*.js,!**/*min.js\" --config-file \"uglify.json\"",
  }
}

My uglify.json:

{
  "sourceMap": {
    "root": "assets/js",
    "url": "{file}.map"
  }
}

I'm not sure, that is related to uglifyjs-folder, maybe the terser module cause this, but I havo no experience with nodejs at all.
I appreciate any help.

Thanks,
Norbert