Each async function always returns a Promise. Inside the async function, we fulfill the result Promise viareturn(line A): asyncfunctionasyncFunc() {return123;// (A)}asyncFunc().then(result=>{assert.equal(result,123);}); As usual, if we don’t explicitly return anything,undefinedis return...
This is hard to explain, so I'll try my best. When using Webpack 3.5 + UglifyES + React Loadable, some of my default exports via import() are undefined and missing. For example, here's the output of the import() result in the latest Webpack. Which in turn causes React to throw ...
exportfunctionuseAsyncState(promise,initialState){conststate=ref(initialState);constisReady=ref(false);constisLoading=ref(false);consterror=ref(undefined);asyncfunctionexecute(){error.value=undefined;isReady.value=false;isLoading.value=true;try{constdata=awaitpromise;state.value=data;isReady.value=true;}...
Type:Function Decide if a retry should occur based on the error. Returning true triggers a retry, false aborts with the error. It is not called forTypeError(except network errors) andAbortError. importpRetryfrom'p-retry';construn=async()=>{…};constresult=awaitpRetry(run,{shouldRetry:erro...
return inMemoryCache[user.id];// returning a synchronous value!} returngetUserAccountById(user.id);// returning a promise!}).then(function (userAccount) {// I got a user account!}); 函数什么都不返回等于返回了 undefined 目前为止,我们看到给 .then() 传递的都是函数,但是其实它可以接受非函数...
// setting context.delegate to null, and returning the ContinueSentinel. function maybeInvokeDelegate(delegate, context) { var method = delegate.iterator[context.method]; if (method === undefined) { // A .throw or .return when the delegate iterator has no .throw ...
[1,2,3],AsyncSquaringLibrary.square,function(err,result){// result is [NaN, NaN, NaN]// This fails because the `this.squareExponent` expression in the square// function is not evaluated in the context of AsyncSquaringLibrary, and is// therefore undefined.});async.map([1,2,3],Async...
C# Function return string value C# length of digit after decimal point c# regular expression to only allow 1 or 2 digits only c# show hide div from code behind OnClick of C# syntax to Generate Sequence number with Prefix C# textarea object C# TextBox Value Set With Variable C# to VB.ne...
createKey(args) - defaults to { return JSON.stringify(args); }, use this to customize how unique function calls are recognized ignoreSingleUndefined - defaults to false. In the calls above, doing sleep(100).then(debounced) is considered different from sleep(100).then(() => debounced())...
(Not returning 5!)function myReq(url) { return new Promise((resolve, reject) => { setTimeout(() => { resolve(5); }, 5000); });}// Option 1myReq('someurl').then((data) => { console.log('data (option 1)', data); // You can use the data here, inside the 'then' blo...