Importing moment in Angular 6

Question

I imported moment in angular 6:

import moment from 'moment'

and

let formatted = moment(startDate).tz(timezone).format();

which seems to work fine...but ng serve outputs the following error:

Module '"/my/project/node_modules/moment/moment"' has no default export.

OK, I understand this error; it says that moment is not exported as default...but when I try to export this way:

import { moment } from 'moment'

but than, error says that moment is in fact an object, not a function.

How did it work in the first step than? How should I import the "moment"?

UPDATE I also tried as suggested in the other question...

import * as moment from 'moment';

But than I got the following result:

ERROR in node_modules/@angular/core/src/render3/ng_dev_mode.d.ts(9,11): error TS2451: Cannot redeclare block-scoped variable 'ngDevMode'.
node_modules/angular-moment-timezone/node_modules/@angular/core/src/render3/ng_dev_mode.d.ts(9,11): error TS2451: Cannot redeclare block-scoped variable 'ngDevMode'.

Solution 1

I found a solution...Firstly I suggest to review this issue page.

1. I abandoned angular-moment-timezone and started using moment-timezone, the reason for ngDevMode error is angular-moment-timezone package has another node-modules inside it. This is a terrible package managing.

2. I than imported as:

   import * as moment from 'moment'; import 'moment-timezone';

and now my code is working...also the project builds.

Solution 2

Try the following to import moment:

import * as moment from 'moment';

Hopefully that helps!

Comments

[VincenzoC]

Possible duplicate of How can moment.js be imported with typescript?

[Heretic Monkey]

Consider using Luxon which is a modern rewrite of Moment.

[amedina]

@HereticMonkey Wow, useful!

[tolga]

No this is not a duplicate. The solution in that answer doesn't solve my problem. I explained with the UPDATE

[Alexander Staroselsky]

Your issue is related to the library angular-moment-timezone, not moment specifically. Try using moment-timezone instead.

[tolga]

Please see the update in my question, I also have a problem with this solution.

[Alexander Staroselsky]

You’re indicating that if you remove this import and anything related to moment in your code, you do no see this issue when running build?

[tolga]

I can run the code with "import moment from 'moment'"... but I can't build or start ng serve again. This is what I found strange.

[Alexander Staroselsky]

That is a bigger issue potentially that can be resolved with updating versions of Angular. github.com/angular/angular/issues/21670

[Alexander Staroselsky]

So your issue looks to be with angular-moment-timezone library specifically. Can you just use moment-timezone instead? Try even removing angular moment timezone and removing any code related to timezone and it should build.