Given an array of asynchronous functions functions, return a new promise promise. Each function in the array accepts no arguments and returns a promise. All the promises should be executed in parallel.
promise resolves:
promise rejects:
Please solve it without using the built-in Promise.all function.
Examples
Example 1
Input: functions = [
() => new Promise(resolve => setTimeout(() => resolve(5), 200))
]
Output: {"t": 200, "resolved": [5]}
Explanation:
promiseAll(functions).then(console.log); // [5]
The single function was resolved at 200ms with a value of 5.
Example 2
Input: functions = [
() => new Promise(resolve => setTimeout(() => resolve(1), 200)),
() => new Promise((resolve, reject) => setTimeout(() => reject("Error"), 100))
]
Output: {"t": 100, "rejected": "Error"}
Explanation: Since one of the promises rejected, the returned promise also rejected with the same error at the same time.
Example 3
Input: functions = [
() => new Promise(resolve => setTimeout(() => resolve(4), 50)),
() => new Promise(resolve => setTimeout(() => resolve(10), 150)),
() => new Promise(resolve => setTimeout(() => resolve(16), 100))
]
Output: {"t": 150, "resolved": [4, 10, 16]}
Explanation: All the promises resolved with a value. The returned promise resolved when the last promise resolved.
Constraints
functions is an array of functions that returns promises
1 <= functions.length <= 10
2721. Execute Asynchronous Functions in Parallel
Medium
30 Points
Given an array of asynchronous functions functions, return a new promise promise. Each function in the array accepts no arguments and returns a promise. All the promises should be executed in parallel.
promise resolves:
promise rejects:
Please solve it without using the built-in Promise.all function.
Examples
Example 1
Input: functions = [
() => new Promise(resolve => setTimeout(() => resolve(5), 200))
]
Output: {"t": 200, "resolved": [5]}
Explanation:
promiseAll(functions).then(console.log); // [5]
The single function was resolved at 200ms with a value of 5.
Example 2
Input: functions = [
() => new Promise(resolve => setTimeout(() => resolve(1), 200)),
() => new Promise((resolve, reject) => setTimeout(() => reject("Error"), 100))
]
Output: {"t": 100, "rejected": "Error"}
Explanation: Since one of the promises rejected, the returned promise also rejected with the same error at the same time.
Example 3
Input: functions = [
() => new Promise(resolve => setTimeout(() => resolve(4), 50)),
() => new Promise(resolve => setTimeout(() => resolve(10), 150)),
() => new Promise(resolve => setTimeout(() => resolve(16), 100))
]
Output: {"t": 150, "resolved": [4, 10, 16]}
Explanation: All the promises resolved with a value. The returned promise resolved when the last promise resolved.
Constraints
functions is an array of functions that returns promises
1 <= functions.length <= 10
Execute Asynchronous Functions in Parallel - Practice Coding | SlaveCode