@idris-maps/yyyy-mm-dd/dist/weekdayIndex.js

A date library dealing only with days in the YYYY-MM-DD format

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.default = (function (day) {
    var d = new Date(day);
    var dayNum = d.getDay() - 1;
    return dayNum === -1 ? 6 : dayNum;
});