flags/flags.js

const $isset = (flag, flags = 0) => (flags & flag) === flag;
const $set = (flag, flags = 0) => flags | flag;
const $unset = (flag, flags = 0) => flags ^ flag;
const $toggle = (flag, flags = 0) => $isset(flag, flags) ? $unset(flag, flags) : $set(flag, flags);
const combine = (...options) => options.reduce((flags, flag) => $set(flag, flags), 0);
const createMultiFlagHandler = (fn) => (...options) => (flags = 0) => fn(combine(...options), flags);
const set = createMultiFlagHandler($set);
const unset = createMultiFlagHandler($unset);
const toggle = createMultiFlagHandler($toggle);
const isset = createMultiFlagHandler($isset);
export { combine, set, unset, toggle, isset };