chill-bundles/Resources/public/modules/postal-code/index.js

window.addEventListener('load', function (e) {
    var
            postalCodes = document.querySelectorAll('[data-postal-code]')
            ;

    for (let i = 0; i < postalCodes.length; i++) {
        let
            searchUrl = postalCodes[i].dataset.searchUrl,
            noResultsLabel = postalCodes[i].dataset.noResultsLabel,
            errorLoadLabel = postalCodes[i].dataset.errorLoadLabel,
            searchingLabel  = postalCodes[i].dataset.searchingLabel
            ;
        

        $(postalCodes[i]).select2({
            allowClear: true,
            language: {
                errorLoading: function () {
                    return errorLoadLabel;
                },
                noResults: function () {
                    return noResultsLabel;
                },
                searching: function () {
                    return searchingLabel;
                }
            },
            ajax: {
                url: searchUrl,
                dataType: 'json',
                delay: 250
            }
        });
    }
});