the array is as follows
[
{checked: true, index: 0}
{checked: true, index: 1}
{checked: true, index: 2}
{checked: true, index: 3}
{checked: true, index: 4}
{checked: true, index: 5}
{checked: true, index: 1}
]output
[checked:true, index: 1]
the array is as follows
[
{checked: true, index: 0}
{checked: true, index: 1}
{checked: true, index: 2}
{checked: true, index: 3}
{checked: true, index: 4}
{checked: true, index: 5}
{checked: true, index: 1}
]output
[checked:true, index: 1]const arr = [
{checked: true, index: 0},
{checked: true, index: 1},
{checked: true, index: 2},
{checked: true, index: 3},
{checked: true, index: 4},
{checked: true, index: 5},
{checked: true, index: 1}
]
const mapper = {}
const newArr = []
for (let item of arr) {
const {index, checked} = item
if (mapper[index]) {
newArr.push(item)
} else {
mapper[index] = true
}
}
console.log(newArr)const a = [
{checked: true, index: 0},
{checked: true, index: 1},
{checked: true, index: 2},
{checked: true, index: 3},
{checked: true, index: 4},
{checked: true, index: 5},
{checked: true, index: 1}
]
const result = Array.from(a.reduce((m, t) => m.set(t.place, t), new Map()).values());Previous: How to translate: vanilla JavaScript?
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