Javascript promise loop

ES6 Native Promise Loop

ES6 Native Promise Loop
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Promise.resolve(0).then(function loop(i) {
return new Promise(function(resolve, reject) {
setTimeout(function() {
console.log(i);
resolve(i+1);
}, 100);
})
.then(loop);
});

ES6 Native Promise while Loop

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function action(i) {
console.log(i);
return {
done: i > 9,
value: i+1
};
}
function loop(promise, fn) {
return promise.then(fn).then(function(wrapper) {
return !wrapper.done ? loop(Promise.resolve(wrapper.value), fn): wrapper.value;
});
}
loop(Promise.resolve(0), action).then(function(value) {console.log('end: ' + value)});

One more example

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function callFun(testclass){
return new Promise(function (resolve, reject) {
// Do some Async stuff
// call resolve if it succeeded
// reject if it failed
});
}
Promise.resolve(0).then(function loop(i) {
// The loop check
if (i < arrayList.length) { // The post iteration increment
return callFun(arrayList[i]).then(function(){
// console.log(i);
return (i + 1);
}).then(loop);
}
}).then(function() {
console.log('error', e);
}).catch(function(e) {
console.log('error', e);
appendError(e);
});