type newable<T> = new (cls: newable<T>) => T;

export default abstract class AbstractFields<T extends AbstractFields<any>> {
    protected constructor(protected readonly cls: newable<T>) {
    }

    public with(property: keyof T & string, value: string | number): T {
        const newInstance: T = new this.cls(this.cls);

        for (const [k, v] of Object.entries(this)) {
            newInstance[k] = v;
        }
        newInstance[property as string] = value;

        return newInstance;
    }
}