function parallel(funcArray, doneAll) {
const newArray = [];
const result = funcArray.map(item => new Promise(resolve => item(resolve)));
const array = result.reduce((a, curr, i, array) => {
return a.then((res) => {
curr.then(res => {
newArray.push(res);
if (array.length === i+1) {
doneAll(newArray);
}
})
return curr
});
}, Promise.resolve());
}
function inSeries(funcArray, doneAll) {
const newArray = [];
const array = funcArray.reduce((a, curr, i, array) =>
a.then(
() => new Promise(
resolve => {
curr(resolve)
}).then(res => {
newArray.push(res);
if (array.length === i+1) {
doneAll(newArray);
}
})
),
Promise.resolve())
}
var a = function(done) {
setTimeout(function() {
done('result a');
}, 600);
};
var b = function(done) {
setTimeout(function() {
done('result b');
}, 200);
};
parallel([a,b], function(results) {
console.log(results); // ['result a', 'result b']
});
inSeries([a,b], function(results) {
console.log(results); // ['result a', 'result b']
});
function(done) {
setTimeout(function() {
done('result');
}, duration);
};new Promise(resolve => {
setTimeout(resolve, duration, 'result');
});function all(promises, done) {
const results = [];
let count = promises.length;
const checkDone = () => {
if (--count === 0) done(results);
};
promises.forEach((p, i) => {
p.then(x => results[i] = x).then(checkDone);
});
}function promiseAll(promises) {
return new Promise(resolve => {
const results = [];
let count = promises.length;
const checkDone = () => {
if (--count === 0) resolve(results);
};
promises.forEach((p, i) => {
p.then(x => results[i] = x).then(checkDone);
});
});
}