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Discussion on: Implementing our own Array.map() method in javascript

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akanshgulati profile image
Akansh •

@diliptwit291 The above implementation fails for

[1,2,3, null, , 4].mymap(a => +a);
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Gives, different results from map

.mymap => [1, 2, 3, 0, NaN, 4]
.map => [1, 2, 3, null, undefined, 4]
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ashwaniweb profile image
Worried Indian • • Edited

Array.prototype.myMap= function (callback) {
let result = this;
for (let index = 0; index < this.length; index++) {
if (this[index] === undefined) {
break;
}
result[index] = callback(this[index], index, this);
}
return result;
};