CaloTech, Computer Technologies. Testing Out Promise.All Catch, Await, Async

#promise catch err, catch returns nothing, b:undefined, logged er. throw must be out of settimeout body async function get(){return new Promise((res,rej)=>{ throw "er";setTimeout(()=> {console.log(3);res(2)},3000)});} var b= await Promise.all([get()]).catch(er=>console.log(er))
#promise.all return value, an array of promises resolve [2] below. async function get(){return new Promise((res,rej)=>{setTimeout(()=>{console.log(3);res(2)},3000)});} var b=await Promise.all([get()])
#await no promise, output: directly 7 await console.log(7);
#await no effect without promise, output, b:8 function g1(){return 8;} var b=await g1(); #one promise errors out, output, a:undefined async function get(){return new Promise((res,rej)=>{setTimeout(()=>{console.log(3);res(2)},3000)});} async function get1(){return new Promise((res,rej)=>{ throw "er";setTimeout(()=>{console.log(3);res(2)},3000)});} var a=Promise.all([get(),get1()]).catch((e)=>console.log(e)) var a=await Promise.all([get(),get1()]).catch((e)=>console.log(e))
#promise.all no error, with catch or not, both output: a:[2,3] async function get(){return new Promise((res,rej)=>{setTimeout(()=>{console.log(3);res(2)},3000)});} async function get1(){return new Promise((res,rej)=>{ setTimeout(()=>{console.log(3);res(3)},3000)});} var a=await Promise.all([get(),get1()]) var a=await Promise.all([get(),get1()]).catch((e)=>console.log(e))