Momentjs in Polymer WebComponent - global is undefined

Question

I want to use momentjs in a webcomponent for a custom card in home-assistant

When I try to import the library, I get the following error:

Cannot set property 'moment' of undefined

import './lib/moment.min.js';

class ContentCardExample extends HTMLElement {
    ...
}

Any idea what is going on?

Answer 1

If you installed moment from npm, you should import it as:

import moment from 'moment/src/moment.js';

and include any locales like this (in case you need them:

import 'moment/src/locale/es.js';