export const isArray = function(a) { return (!!a) && (a.constructor === Array); }; export const isObject = function(a) { return (!!a) && (a.constructor === Object); }; export const isDate = function(o) { return o instanceof Object && o.constructor === Date; } export const has = function(o,p){ let has = true for (const prop of p) { has = o.hasOwnProperty(prop) if(!has) break; } return has; } export const querablePromise = function(promise) { // Don't modify any promise that has been already modified. if (promise.isPending) return promise; // Setup our initial state. const state = { isPending: true, isRejected: false, isResolved: false, // Specified so that we'll generate accessor functions for them. err: undefined, val: undefined, }; // We must actually wait for the promise to either resolve or reject, // wrap that value, then let it continue on. const result = promise.then( function(val) { state.isResolved = true; state.isPending = false; state.val = val; return val; }, function(err) { state.isRejected = true; state.isPending = false; state.err = err; throw err; } ); for (const val of Object.keys(state)) { result[val] = function() { return state[val]; }; } return result; }