I need to find the index of an array of array object where it is true. My array:
[
[
{id: 1, status: false},
{id: 2, status: true}
],
[
{id: 13, status: false},
{id: 14, status: false}
],
[
{id: 18, status: true},
{id: 19, status: false}
]
]
In the case above I should expect index 0 and 2 to be returned.
Use reduce to get indices of the elements where some items fulfill the condition:
input.reduce((acc, arr, i) => (
arr.some(obj => obj.status) && acc.push(i)
, acc), [])
const input = [[{"id":1,"status":false},{"id":2,"status":true}],[{"id":13,"status":false},{"id":14,"status":false}],[{"id":18,"status":true},{"id":19,"status":false}]];
const result = input.reduce((acc, arr, i) => (
arr.some(obj => obj.status) && acc.push(i)
, acc), []);
console.log(result);There are two steps in the solution of the problem.
const data = [
[
{ id: 1, status: false },
{ id: 2, status: true },
],
[
{ id: 13, status: false },
{ id: 14, status: false },
],
[
{ id: 18, status: true },
{ id: 19, status: false },
],
];
let ret = [];
data.forEach((x, i) => {
if (x.some((y) => y.status)) ret.push(i);
});
console.log(ret);
ret = [];
data.forEach((x, i) => {
if (x.filter((y) => y.status).length > 0) ret.push(i);
});
console.log(ret);I have used both some and filter methods to check the condition and for array traversese I have used array forEach method.
filter. some was created to take care of such cases - it clearly states the purpose of the code, using filter here just adds an unnecessary cognitive and performance burden.Basically same solution as from marzelin, but more readable in my opinion. The comma operator in the callback return value can be quite confusing.
const data = [
[
{id: 1, status: false},
{id: 2, status: true}
],
[
{id: 13, status: false},
{id: 14, status: false}
],
[
{id: 18, status: true},
{id: 19, status: false}
]
]
//pV=previous value, cV=current value, cI=current index
const result = data.reduce(function (pV, cV, cI) {
if (cV.some(function (obj) {
return obj.status
})) {
pV.push(cI);
}
return pV;
},[]);
console.log(result);
[0, 2]: "What are the indices of the arrays in the outer array that have some element in them withstatusoftrue?" But it is also the answer to a very different question: " For what indices are there inner arrays where the value at that index hasstatusoftrue?" Which do you mean?