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Cannot read property 'extend' of undefined

See original GitHub issue

I load these scripts in my head:

 <script src="js/jquery.min.js" defer></script>
 <script src="https://unpkg.com/leaflet@latest/dist/leaflet.js" defer></script> 
 <script src="https://unpkg.com/leaflet-control-geocoder@latest/dist/Control.Geocoder.js"></script>
 <script src="js/siteworks.js" defer></script>

I create a map which is displayed correctly and when I add the geocoder L.Control.geocoder().addTo(map); I get this error:

Uncaught TypeError: Cannot read property 'extend' of undefined at nominatim.js:5 at index.js:42

nominatim.js:

import L from 'leaflet';
import { template, getJSON } from '../util';

export default {
  class: L.Class.extend({          <--
    options: {
    .
    .
    .

Issue Analytics

State:
Created 5 years ago
Comments:11 (2 by maintainers)

Top GitHub Comments

2reactions

googlsuxcommented, Jan 11, 2019

This has nothing to do with the other scripts eg. siteworks. Even a minimal HTML that does nothing shows this error after load in Chrome console:

<!DOCTYPE html>
<html>
    <head>
	<link rel="stylesheet" href="https://unpkg.com/leaflet@latest/dist/leaflet.css" />
	<link rel="stylesheet" href="Control.Geocoder.css" />
	<script src="Control.Geocoder.js"></script>
	<script src="https://unpkg.com/leaflet@latest/dist/leaflet-src.js"></script>
    </head>
    <body>
    </body>
</html>

Result:

nominatim.js:5 Uncaught TypeError: Cannot read property ‘extend’ of undefined at nominatim.js:5 at index.js:42

Very unprofessional, what is the source of this problem??

1reaction

perliedmancommented, May 11, 2020

@leonheess Yeah, sorry about closing it abruptly, but if you read my response, it says:

I suspect a similar problem in the first case: L.Class.extend is a function in Leaflet, it’s not something that this plugin has invented.

And I stand by the important part: without a reproducible, running example, it is usually impossible as a maintainer to find out what is happening. A few <script> tags and an error message is rarely enough, unless it’s a problem you have seen before.

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