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[Comment from a deleted post]
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casperns profile image
Zelimir Stefanovic •

Nice example. Also, another way:

let sett = new Set();
return arr.map((v, index) => { 
   if(sett12.has(v.id)) {
       return false
   } else {
       sett12.add(v.id);
       return index;
   } 
});

Or if we want just unique values then:

function noDuplicates(arr) {
    return [...new Set(arr.map(v => v.id))];
}
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sait profile image
Sai gowtham •

wow, good solution.

The final solution with typos fixed.

function getUnique(arr){
let set = new Set();
return arr.map((v, index) => { 
   if(set.has(v.id)) {
       return false
   } else {
       set.add(v.id);
       return index;
   } 
  }).filter(e=>e).map(e=>arr[e]);


}
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tcomtom profile image
Tom Shimada •

This was a great article. This helped me with my project. I was using faker to create some data but faker created duplicate names in an array of objects, but the client didn't want any duplicates.

Worked perfectly Thanks!!

Still trying to understand the code though.

Especially
.filter(e=>e).map(e=>arr[e]);

Gotta dig deeper with map and filter!

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nikolicstjepan profile image
Nikolić Stjepan •

filter(e=>e) part fails if e (index) is 0.

Should be: filter(e => e || e === 0)