Class for creating multi inheritance. https://www.codeproject.com/Articles/1189466/JavaScript-ES-Multiple-Inheritance-Class

multi.inheritance.js

// Class for creating multi inheritance.
class multi {
    // Inherit method to create base classes.
    static inherit(..._bases) {
        class classes {

            // The base classes
            get base() {
                return _bases;
            }

            constructor(..._args) {
                var index = 0;

                for (let b of this.base) {
                    let obj = new b(_args[index++]);
                    multi.copy(this, obj);
                }
            }

        }

        // Copy over properties and methods
        for (let base of _bases) {
            multi.copy(classes, base);
            multi.copy(classes.prototype, base.prototype);
        }

        return classes;
    }

    // Copies the properties from one class to another
    static copy(_target, _source) {
        for (let key of Reflect.ownKeys(_source)) {
            if (key !== "constructor" && key !== "prototype" && key !== "name") {
                let desc = Object.getOwnPropertyDescriptor(_source, key);
                Object.defineProperty(_target, key, desc);
            }
        }
    }
}

module.exports = multi;

/**********/
/* Sample */
/**********/

// Single Inherit
class person extends ages

// Multi Inherit
class person extends multi.inherit(ages, genders)