painor/example.js

## example.js
function f() {
    console.log('ok')
}

module.exports = {
    f,
}

## f1.js
import { f } from './gramjs.js'

f()

## file.html
<html>
<head>
    <title>Title</title>
    <script type="module" src="f1.js"></script>
</head>
<body>

</body>
<script>


</script>
</html>

## webpack.config.babel.js
module.exports = {
    entry: './example.js',
    mode: 'development',
    node: {
        fs: 'empty',
    },
    module: {
        rules: [{
            test: /\.js$/,
            use: {

                loader: 'babel-loader',
                options: {
                    presets: [
                        '@babel/preset-env',
                    ],
                    plugins: [
                        '@babel/plugin-proposal-class-properties',
                    ],
                },
            },
        },
        ],
    },
    output: {
        path: __dirname,
        filename: 'gramjs.js',
        library: 'gramjs',
        libraryTarget: 'umd',

    },
}
	<html>
	<head>
	<title>Title</title>
	<script type="module" src="f1.js"></script>
	</head>
	<body>

	</body>
	<script>


	</script>
	</html>
	module.exports = {
	entry: './example.js',
	mode: 'development',
	node: {
	fs: 'empty',
	},
	module: {
	rules: [{
	test: /\.js$/,
	use: {

	loader: 'babel-loader',
	options: {
	presets: [
	'@babel/preset-env',
	],
	plugins: [
	'@babel/plugin-proposal-class-properties',
	],
	},
	},
	},
	],
	},
	output: {
	path: __dirname,
	filename: 'gramjs.js',
	library: 'gramjs',
	libraryTarget: 'umd',

	},
	}