Filtering duplicate hashes from array of hashes

Filtering duplicate hashes from array of hashes - Javascript

I have an array of hashes, like this:

[{id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c6941735", name: "skandi"},

 {id: "4bf58dd8d48988d147941735", name: "diner"},

 {id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d14a941735", name: "vietnam"},

 {id: "4bf58dd8d48988d1ce941735", name: "fish"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"}]

I want to throw out duplicate hashes. Set doesn't work because hashes are unique objects.

I feel stuck and need a kick to think. Please advise!

edited Dec 21 '18 at 11:07

Kamil Kiełczewski

13.4k87297

asked Dec 21 '18 at 9:40

Dende

103210

2

Reduce the array to an object, using the id as key, and then convert back to array using Object.values().

– Ori Drori
Dec 21 '18 at 9:44

What you tried?

– ZiTAL
Dec 21 '18 at 9:45

You would have to loop through the array for each possible hash and check, remove. Or change the data format, use an object with the hash string as a key and the name and whatever else as a separate object for the value

– Patrick Evans
Dec 21 '18 at 9:46

Only pure JS allowed?

– hindmost
Dec 21 '18 at 9:49

@hindmost, yes, this is part of my react app

– Dende
Dec 21 '18 at 9:52

|
show 3 more comments

I have an array of hashes, like this:

[{id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c6941735", name: "skandi"},

 {id: "4bf58dd8d48988d147941735", name: "diner"},

 {id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d14a941735", name: "vietnam"},

 {id: "4bf58dd8d48988d1ce941735", name: "fish"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"}]

I want to throw out duplicate hashes. Set doesn't work because hashes are unique objects.

I feel stuck and need a kick to think. Please advise!

edited Dec 21 '18 at 11:07

Kamil Kiełczewski

13.4k87297

asked Dec 21 '18 at 9:40

Dende

103210

2

Reduce the array to an object, using the id as key, and then convert back to array using Object.values().

– Ori Drori
Dec 21 '18 at 9:44

What you tried?

– ZiTAL
Dec 21 '18 at 9:45

You would have to loop through the array for each possible hash and check, remove. Or change the data format, use an object with the hash string as a key and the name and whatever else as a separate object for the value

– Patrick Evans
Dec 21 '18 at 9:46

Only pure JS allowed?

– hindmost
Dec 21 '18 at 9:49

@hindmost, yes, this is part of my react app

– Dende
Dec 21 '18 at 9:52

|
show 3 more comments

I have an array of hashes, like this:

[{id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c6941735", name: "skandi"},

 {id: "4bf58dd8d48988d147941735", name: "diner"},

 {id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d14a941735", name: "vietnam"},

 {id: "4bf58dd8d48988d1ce941735", name: "fish"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"}]

I want to throw out duplicate hashes. Set doesn't work because hashes are unique objects.

I feel stuck and need a kick to think. Please advise!

edited Dec 21 '18 at 11:07

Kamil Kiełczewski

13.4k87297

asked Dec 21 '18 at 9:40

Dende

103210

I have an array of hashes, like this:

[{id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c6941735", name: "skandi"},

 {id: "4bf58dd8d48988d147941735", name: "diner"},

 {id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d14a941735", name: "vietnam"},

 {id: "4bf58dd8d48988d1ce941735", name: "fish"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"}]

I want to throw out duplicate hashes. Set doesn't work because hashes are unique objects.

I feel stuck and need a kick to think. Please advise!

javascript arrays hash

edited Dec 21 '18 at 11:07

Kamil Kiełczewski

13.4k87297

asked Dec 21 '18 at 9:40

Dende

103210

edited Dec 21 '18 at 11:07

Kamil Kiełczewski

13.4k87297

asked Dec 21 '18 at 9:40

Dende

103210

edited Dec 21 '18 at 11:07

Kamil Kiełczewski

13.4k87297

edited Dec 21 '18 at 11:07

Kamil Kiełczewski

13.4k87297

edited Dec 21 '18 at 11:07

Kamil Kiełczewski

13.4k87297

asked Dec 21 '18 at 9:40

Dende

103210

asked Dec 21 '18 at 9:40

Dende

103210

asked Dec 21 '18 at 9:40

Dende

103210

2

Reduce the array to an object, using the id as key, and then convert back to array using Object.values().

– Ori Drori
Dec 21 '18 at 9:44

What you tried?

– ZiTAL
Dec 21 '18 at 9:45

You would have to loop through the array for each possible hash and check, remove. Or change the data format, use an object with the hash string as a key and the name and whatever else as a separate object for the value

– Patrick Evans
Dec 21 '18 at 9:46

Only pure JS allowed?

– hindmost
Dec 21 '18 at 9:49

@hindmost, yes, this is part of my react app

– Dende
Dec 21 '18 at 9:52

|
show 3 more comments

2

Reduce the array to an object, using the id as key, and then convert back to array using Object.values().

– Ori Drori
Dec 21 '18 at 9:44

What you tried?

– ZiTAL
Dec 21 '18 at 9:45

You would have to loop through the array for each possible hash and check, remove. Or change the data format, use an object with the hash string as a key and the name and whatever else as a separate object for the value

– Patrick Evans
Dec 21 '18 at 9:46

Only pure JS allowed?

– hindmost
Dec 21 '18 at 9:49

@hindmost, yes, this is part of my react app

– Dende
Dec 21 '18 at 9:52

Reduce the array to an object, using the id as key, and then convert back to array using Object.values().

– Ori Drori
Dec 21 '18 at 9:44

What you tried?

– ZiTAL
Dec 21 '18 at 9:45

You would have to loop through the array for each possible hash and check, remove. Or change the data format, use an object with the hash string as a key and the name and whatever else as a separate object for the value

– Patrick Evans
Dec 21 '18 at 9:46

Only pure JS allowed?

– hindmost
Dec 21 '18 at 9:49

@hindmost, yes, this is part of my react app

– Dende
Dec 21 '18 at 9:52

|
show 3 more comments

4 Answers
4

active

oldest

votes

You can use reduce too

//I added comma to each object

const data= [{id: "4bf58dd8d48988d110941735", name: "italy"},

    {id: "4bf58dd8d48988d1c6941735", name: "skandi"},

    {id: "4bf58dd8d48988d147941735", name: "diner"},

    {id: "4bf58dd8d48988d110941735", name: "italy"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"},

    {id: "4bf58dd8d48988d14a941735", name: "vietnam"},

    {id: "4bf58dd8d48988d1ce941735", name: "fish"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"}]



const result= data.reduce((current,next)=>{   

    if(!current.some(a=> a.name === next.name)){

        current.push(next);

    }

    return current;

},)

console.log(result);

edited Dec 21 '18 at 11:50

answered Dec 21 '18 at 10:04

Just code

10.5k53267

add a comment |

Try this

h.filter(( t={}, a=>!(t[a.id]=a.id in t) ))

Input array in h, time complexity O(n), explanation here.

let h = [{id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c6941735", name: "skandi"},

 {id: "4bf58dd8d48988d147941735", name: "diner"},

 {id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d14a941735", name: "vietnam"},

 {id: "4bf58dd8d48988d1ce941735", name: "fish"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"}]

 

 let t; // declare t to avoid use global (however works without it too)

 let r= h.filter(( t={}, a=>!(t[a.id]=a.id in t) ))



 

 console.log(JSON.stringify(r));

edited Jan 14 at 3:41

answered Dec 21 '18 at 9:45

Kamil Kiełczewski

13.4k87297

add a comment |

Space for time

let arr = [

    { id: '4bf58dd8d48988d110941735', name: 'italy' },

    { id: '4bf58dd8d48988d1c6941735', name: 'skandi' },

    { id: '4bf58dd8d48988d147941735', name: 'diner' },

    { id: '4bf58dd8d48988d110941735', name: 'italy' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' },

    { id: '4bf58dd8d48988d14a941735', name: 'vietnam' },

    { id: '4bf58dd8d48988d1ce941735', name: 'fish' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' }

]



let map = {};

let rest = arr.filter((item) => {

    if(map[item.id] === void 0) {

        map[item.id] = item.id;

        return true;

    }

});

map = null;



console.log(rest);

answered Dec 21 '18 at 10:03

zheng li

6917

add a comment |

I would suggest an approach with associative arrays, this makes duplicate removal easier. If you can, you should build your array as an associative array in the first place, so that you don't have to convert it. Here is how you do it:

var array = [{

    id: "4bf58dd8d48988d110941735",

    name: "italy"

  },

  {

    id: "4bf58dd8d48988d1c6941735",

    name: "skandi"

  }, {

    id: "4bf58dd8d48988d147941735",

    name: "diner"

  }, {

    id: "4bf58dd8d48988d110941735",

    name: "italy"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }, {

    id: "4bf58dd8d48988d14a941735",

    name: "vietnam"

  }, {

    id: "4bf58dd8d48988d14a941735",

    name: "fish"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }

];



// you can access the array with arrayAssociative[id], where the id is the real id like "4bf58dd8d48988d110941735"

var arrayAssociative = {};

for (item in array) {

  // first get the unique id's

  var addedNode = arrayAssociative[array[item].id] = arrayAssociative[array[item].id] || {};

  if (addedNode.names == null)

    addedNode.names = {};

  // now get the unique names

  var addedName = arrayAssociative[array[item].id].names[array[item].name] = arrayAssociative[array[item].id].names[array[item].name] || {};

}

console.log(arrayAssociative);

I don't know the exact reason, why the line

var element = arrayAssociative[id] =arrayAssociative[id] || {};

works for this, but let's just accept the funcitonality as it is :)

edited Dec 21 '18 at 10:00

answered Dec 21 '18 at 9:52

Stephan T.

1,2821921

1

arrayAssociative[array[item].id] || {} this line gives value in left of || if it is not null/undefined/0/false or value in the right if opposit - stackoverflow.com/q/2100758/860099

– Kamil Kiełczewski
Dec 21 '18 at 10:03

thanks for the explanation <3

– Stephan T.
Dec 21 '18 at 10:05

add a comment |

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4 Answers
4

active

oldest

votes

4 Answers
4

active

oldest

votes

You can use reduce too

//I added comma to each object

const data= [{id: "4bf58dd8d48988d110941735", name: "italy"},

    {id: "4bf58dd8d48988d1c6941735", name: "skandi"},

    {id: "4bf58dd8d48988d147941735", name: "diner"},

    {id: "4bf58dd8d48988d110941735", name: "italy"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"},

    {id: "4bf58dd8d48988d14a941735", name: "vietnam"},

    {id: "4bf58dd8d48988d1ce941735", name: "fish"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"}]



const result= data.reduce((current,next)=>{   

    if(!current.some(a=> a.name === next.name)){

        current.push(next);

    }

    return current;

},)

console.log(result);

edited Dec 21 '18 at 11:50

answered Dec 21 '18 at 10:04

Just code

10.5k53267

add a comment |

You can use reduce too

//I added comma to each object

const data= [{id: "4bf58dd8d48988d110941735", name: "italy"},

    {id: "4bf58dd8d48988d1c6941735", name: "skandi"},

    {id: "4bf58dd8d48988d147941735", name: "diner"},

    {id: "4bf58dd8d48988d110941735", name: "italy"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"},

    {id: "4bf58dd8d48988d14a941735", name: "vietnam"},

    {id: "4bf58dd8d48988d1ce941735", name: "fish"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"}]



const result= data.reduce((current,next)=>{   

    if(!current.some(a=> a.name === next.name)){

        current.push(next);

    }

    return current;

},)

console.log(result);

edited Dec 21 '18 at 11:50

answered Dec 21 '18 at 10:04

Just code

10.5k53267

add a comment |

You can use reduce too

//I added comma to each object

const data= [{id: "4bf58dd8d48988d110941735", name: "italy"},

    {id: "4bf58dd8d48988d1c6941735", name: "skandi"},

    {id: "4bf58dd8d48988d147941735", name: "diner"},

    {id: "4bf58dd8d48988d110941735", name: "italy"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"},

    {id: "4bf58dd8d48988d14a941735", name: "vietnam"},

    {id: "4bf58dd8d48988d1ce941735", name: "fish"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"}]



const result= data.reduce((current,next)=>{   

    if(!current.some(a=> a.name === next.name)){

        current.push(next);

    }

    return current;

},)

console.log(result);

edited Dec 21 '18 at 11:50

answered Dec 21 '18 at 10:04

Just code

10.5k53267

You can use reduce too

//I added comma to each object

const data= [{id: "4bf58dd8d48988d110941735", name: "italy"},

    {id: "4bf58dd8d48988d1c6941735", name: "skandi"},

    {id: "4bf58dd8d48988d147941735", name: "diner"},

    {id: "4bf58dd8d48988d110941735", name: "italy"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"},

    {id: "4bf58dd8d48988d14a941735", name: "vietnam"},

    {id: "4bf58dd8d48988d1ce941735", name: "fish"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"}]



const result= data.reduce((current,next)=>{   

    if(!current.some(a=> a.name === next.name)){

        current.push(next);

    }

    return current;

},)

console.log(result);

//I added comma to each object

const data= [{id: "4bf58dd8d48988d110941735", name: "italy"},

    {id: "4bf58dd8d48988d1c6941735", name: "skandi"},

    {id: "4bf58dd8d48988d147941735", name: "diner"},

    {id: "4bf58dd8d48988d110941735", name: "italy"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"},

    {id: "4bf58dd8d48988d14a941735", name: "vietnam"},

    {id: "4bf58dd8d48988d1ce941735", name: "fish"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"}]



const result= data.reduce((current,next)=>{   

    if(!current.some(a=> a.name === next.name)){

        current.push(next);

    }

    return current;

},)

console.log(result);

//I added comma to each object

const data= [{id: "4bf58dd8d48988d110941735", name: "italy"},

    {id: "4bf58dd8d48988d1c6941735", name: "skandi"},

    {id: "4bf58dd8d48988d147941735", name: "diner"},

    {id: "4bf58dd8d48988d110941735", name: "italy"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"},

    {id: "4bf58dd8d48988d14a941735", name: "vietnam"},

    {id: "4bf58dd8d48988d1ce941735", name: "fish"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"},

    {id: "4bf58dd8d48988d1c4941735", name: "resto"}]



const result= data.reduce((current,next)=>{   

    if(!current.some(a=> a.name === next.name)){

        current.push(next);

    }

    return current;

},)

console.log(result);

edited Dec 21 '18 at 11:50

answered Dec 21 '18 at 10:04

Just code

10.5k53267

edited Dec 21 '18 at 11:50

answered Dec 21 '18 at 10:04

Just code

10.5k53267

answered Dec 21 '18 at 10:04

Just code

10.5k53267

answered Dec 21 '18 at 10:04

Just code

10.5k53267

add a comment |

Try this

h.filter(( t={}, a=>!(t[a.id]=a.id in t) ))

Input array in h, time complexity O(n), explanation here.

let h = [{id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c6941735", name: "skandi"},

 {id: "4bf58dd8d48988d147941735", name: "diner"},

 {id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d14a941735", name: "vietnam"},

 {id: "4bf58dd8d48988d1ce941735", name: "fish"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"}]

 

 let t; // declare t to avoid use global (however works without it too)

 let r= h.filter(( t={}, a=>!(t[a.id]=a.id in t) ))



 

 console.log(JSON.stringify(r));

edited Jan 14 at 3:41

answered Dec 21 '18 at 9:45

Kamil Kiełczewski

13.4k87297

add a comment |

Try this

h.filter(( t={}, a=>!(t[a.id]=a.id in t) ))

Input array in h, time complexity O(n), explanation here.

let h = [{id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c6941735", name: "skandi"},

 {id: "4bf58dd8d48988d147941735", name: "diner"},

 {id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d14a941735", name: "vietnam"},

 {id: "4bf58dd8d48988d1ce941735", name: "fish"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"}]

 

 let t; // declare t to avoid use global (however works without it too)

 let r= h.filter(( t={}, a=>!(t[a.id]=a.id in t) ))



 

 console.log(JSON.stringify(r));

edited Jan 14 at 3:41

answered Dec 21 '18 at 9:45

Kamil Kiełczewski

13.4k87297

add a comment |

Try this

h.filter(( t={}, a=>!(t[a.id]=a.id in t) ))

Input array in h, time complexity O(n), explanation here.

let h = [{id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c6941735", name: "skandi"},

 {id: "4bf58dd8d48988d147941735", name: "diner"},

 {id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d14a941735", name: "vietnam"},

 {id: "4bf58dd8d48988d1ce941735", name: "fish"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"}]

 

 let t; // declare t to avoid use global (however works without it too)

 let r= h.filter(( t={}, a=>!(t[a.id]=a.id in t) ))



 

 console.log(JSON.stringify(r));

edited Jan 14 at 3:41

answered Dec 21 '18 at 9:45

Kamil Kiełczewski

13.4k87297

Try this

h.filter(( t={}, a=>!(t[a.id]=a.id in t) ))

Input array in h, time complexity O(n), explanation here.

let h = [{id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c6941735", name: "skandi"},

 {id: "4bf58dd8d48988d147941735", name: "diner"},

 {id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d14a941735", name: "vietnam"},

 {id: "4bf58dd8d48988d1ce941735", name: "fish"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"}]

 

 let t; // declare t to avoid use global (however works without it too)

 let r= h.filter(( t={}, a=>!(t[a.id]=a.id in t) ))



 

 console.log(JSON.stringify(r));

let h = [{id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c6941735", name: "skandi"},

 {id: "4bf58dd8d48988d147941735", name: "diner"},

 {id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d14a941735", name: "vietnam"},

 {id: "4bf58dd8d48988d1ce941735", name: "fish"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"}]

 

 let t; // declare t to avoid use global (however works without it too)

 let r= h.filter(( t={}, a=>!(t[a.id]=a.id in t) ))



 

 console.log(JSON.stringify(r));

let h = [{id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c6941735", name: "skandi"},

 {id: "4bf58dd8d48988d147941735", name: "diner"},

 {id: "4bf58dd8d48988d110941735", name: "italy"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d14a941735", name: "vietnam"},

 {id: "4bf58dd8d48988d1ce941735", name: "fish"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"},

 {id: "4bf58dd8d48988d1c4941735", name: "resto"}]

 

 let t; // declare t to avoid use global (however works without it too)

 let r= h.filter(( t={}, a=>!(t[a.id]=a.id in t) ))



 

 console.log(JSON.stringify(r));

edited Jan 14 at 3:41

answered Dec 21 '18 at 9:45

Kamil Kiełczewski

13.4k87297

edited Jan 14 at 3:41

answered Dec 21 '18 at 9:45

Kamil Kiełczewski

13.4k87297

answered Dec 21 '18 at 9:45

Kamil Kiełczewski

13.4k87297

answered Dec 21 '18 at 9:45

Kamil Kiełczewski

13.4k87297

add a comment |

Space for time

let arr = [

    { id: '4bf58dd8d48988d110941735', name: 'italy' },

    { id: '4bf58dd8d48988d1c6941735', name: 'skandi' },

    { id: '4bf58dd8d48988d147941735', name: 'diner' },

    { id: '4bf58dd8d48988d110941735', name: 'italy' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' },

    { id: '4bf58dd8d48988d14a941735', name: 'vietnam' },

    { id: '4bf58dd8d48988d1ce941735', name: 'fish' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' }

]



let map = {};

let rest = arr.filter((item) => {

    if(map[item.id] === void 0) {

        map[item.id] = item.id;

        return true;

    }

});

map = null;



console.log(rest);

answered Dec 21 '18 at 10:03

zheng li

6917

add a comment |

Space for time

let arr = [

    { id: '4bf58dd8d48988d110941735', name: 'italy' },

    { id: '4bf58dd8d48988d1c6941735', name: 'skandi' },

    { id: '4bf58dd8d48988d147941735', name: 'diner' },

    { id: '4bf58dd8d48988d110941735', name: 'italy' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' },

    { id: '4bf58dd8d48988d14a941735', name: 'vietnam' },

    { id: '4bf58dd8d48988d1ce941735', name: 'fish' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' }

]



let map = {};

let rest = arr.filter((item) => {

    if(map[item.id] === void 0) {

        map[item.id] = item.id;

        return true;

    }

});

map = null;



console.log(rest);

answered Dec 21 '18 at 10:03

zheng li

6917

add a comment |

Space for time

let arr = [

    { id: '4bf58dd8d48988d110941735', name: 'italy' },

    { id: '4bf58dd8d48988d1c6941735', name: 'skandi' },

    { id: '4bf58dd8d48988d147941735', name: 'diner' },

    { id: '4bf58dd8d48988d110941735', name: 'italy' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' },

    { id: '4bf58dd8d48988d14a941735', name: 'vietnam' },

    { id: '4bf58dd8d48988d1ce941735', name: 'fish' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' }

]



let map = {};

let rest = arr.filter((item) => {

    if(map[item.id] === void 0) {

        map[item.id] = item.id;

        return true;

    }

});

map = null;



console.log(rest);

answered Dec 21 '18 at 10:03

zheng li

6917

Space for time

let arr = [

    { id: '4bf58dd8d48988d110941735', name: 'italy' },

    { id: '4bf58dd8d48988d1c6941735', name: 'skandi' },

    { id: '4bf58dd8d48988d147941735', name: 'diner' },

    { id: '4bf58dd8d48988d110941735', name: 'italy' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' },

    { id: '4bf58dd8d48988d14a941735', name: 'vietnam' },

    { id: '4bf58dd8d48988d1ce941735', name: 'fish' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' }

]



let map = {};

let rest = arr.filter((item) => {

    if(map[item.id] === void 0) {

        map[item.id] = item.id;

        return true;

    }

});

map = null;



console.log(rest);

let arr = [

    { id: '4bf58dd8d48988d110941735', name: 'italy' },

    { id: '4bf58dd8d48988d1c6941735', name: 'skandi' },

    { id: '4bf58dd8d48988d147941735', name: 'diner' },

    { id: '4bf58dd8d48988d110941735', name: 'italy' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' },

    { id: '4bf58dd8d48988d14a941735', name: 'vietnam' },

    { id: '4bf58dd8d48988d1ce941735', name: 'fish' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' }

]



let map = {};

let rest = arr.filter((item) => {

    if(map[item.id] === void 0) {

        map[item.id] = item.id;

        return true;

    }

});

map = null;



console.log(rest);

let arr = [

    { id: '4bf58dd8d48988d110941735', name: 'italy' },

    { id: '4bf58dd8d48988d1c6941735', name: 'skandi' },

    { id: '4bf58dd8d48988d147941735', name: 'diner' },

    { id: '4bf58dd8d48988d110941735', name: 'italy' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' },

    { id: '4bf58dd8d48988d14a941735', name: 'vietnam' },

    { id: '4bf58dd8d48988d1ce941735', name: 'fish' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' },

    { id: '4bf58dd8d48988d1c4941735', name: 'resto' }

]



let map = {};

let rest = arr.filter((item) => {

    if(map[item.id] === void 0) {

        map[item.id] = item.id;

        return true;

    }

});

map = null;



console.log(rest);

answered Dec 21 '18 at 10:03

zheng li

6917

answered Dec 21 '18 at 10:03

zheng li

6917

answered Dec 21 '18 at 10:03

zheng li

6917

answered Dec 21 '18 at 10:03

zheng li

6917

add a comment |

var array = [{

    id: "4bf58dd8d48988d110941735",

    name: "italy"

  },

  {

    id: "4bf58dd8d48988d1c6941735",

    name: "skandi"

  }, {

    id: "4bf58dd8d48988d147941735",

    name: "diner"

  }, {

    id: "4bf58dd8d48988d110941735",

    name: "italy"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }, {

    id: "4bf58dd8d48988d14a941735",

    name: "vietnam"

  }, {

    id: "4bf58dd8d48988d14a941735",

    name: "fish"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }

];



// you can access the array with arrayAssociative[id], where the id is the real id like "4bf58dd8d48988d110941735"

var arrayAssociative = {};

for (item in array) {

  // first get the unique id's

  var addedNode = arrayAssociative[array[item].id] = arrayAssociative[array[item].id] || {};

  if (addedNode.names == null)

    addedNode.names = {};

  // now get the unique names

  var addedName = arrayAssociative[array[item].id].names[array[item].name] = arrayAssociative[array[item].id].names[array[item].name] || {};

}

console.log(arrayAssociative);

I don't know the exact reason, why the line

var element = arrayAssociative[id] =arrayAssociative[id] || {};

works for this, but let's just accept the funcitonality as it is :)

edited Dec 21 '18 at 10:00

answered Dec 21 '18 at 9:52

Stephan T.

1,2821921

1

arrayAssociative[array[item].id] || {} this line gives value in left of || if it is not null/undefined/0/false or value in the right if opposit - stackoverflow.com/q/2100758/860099

– Kamil Kiełczewski
Dec 21 '18 at 10:03

thanks for the explanation <3

– Stephan T.
Dec 21 '18 at 10:05

add a comment |

var array = [{

    id: "4bf58dd8d48988d110941735",

    name: "italy"

  },

  {

    id: "4bf58dd8d48988d1c6941735",

    name: "skandi"

  }, {

    id: "4bf58dd8d48988d147941735",

    name: "diner"

  }, {

    id: "4bf58dd8d48988d110941735",

    name: "italy"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }, {

    id: "4bf58dd8d48988d14a941735",

    name: "vietnam"

  }, {

    id: "4bf58dd8d48988d14a941735",

    name: "fish"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }

];



// you can access the array with arrayAssociative[id], where the id is the real id like "4bf58dd8d48988d110941735"

var arrayAssociative = {};

for (item in array) {

  // first get the unique id's

  var addedNode = arrayAssociative[array[item].id] = arrayAssociative[array[item].id] || {};

  if (addedNode.names == null)

    addedNode.names = {};

  // now get the unique names

  var addedName = arrayAssociative[array[item].id].names[array[item].name] = arrayAssociative[array[item].id].names[array[item].name] || {};

}

console.log(arrayAssociative);

I don't know the exact reason, why the line

var element = arrayAssociative[id] =arrayAssociative[id] || {};

works for this, but let's just accept the funcitonality as it is :)

edited Dec 21 '18 at 10:00

answered Dec 21 '18 at 9:52

Stephan T.

1,2821921

1

arrayAssociative[array[item].id] || {} this line gives value in left of || if it is not null/undefined/0/false or value in the right if opposit - stackoverflow.com/q/2100758/860099

– Kamil Kiełczewski
Dec 21 '18 at 10:03

thanks for the explanation <3

– Stephan T.
Dec 21 '18 at 10:05

add a comment |

var array = [{

    id: "4bf58dd8d48988d110941735",

    name: "italy"

  },

  {

    id: "4bf58dd8d48988d1c6941735",

    name: "skandi"

  }, {

    id: "4bf58dd8d48988d147941735",

    name: "diner"

  }, {

    id: "4bf58dd8d48988d110941735",

    name: "italy"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }, {

    id: "4bf58dd8d48988d14a941735",

    name: "vietnam"

  }, {

    id: "4bf58dd8d48988d14a941735",

    name: "fish"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }

];



// you can access the array with arrayAssociative[id], where the id is the real id like "4bf58dd8d48988d110941735"

var arrayAssociative = {};

for (item in array) {

  // first get the unique id's

  var addedNode = arrayAssociative[array[item].id] = arrayAssociative[array[item].id] || {};

  if (addedNode.names == null)

    addedNode.names = {};

  // now get the unique names

  var addedName = arrayAssociative[array[item].id].names[array[item].name] = arrayAssociative[array[item].id].names[array[item].name] || {};

}

console.log(arrayAssociative);

I don't know the exact reason, why the line

var element = arrayAssociative[id] =arrayAssociative[id] || {};

works for this, but let's just accept the funcitonality as it is :)

edited Dec 21 '18 at 10:00

answered Dec 21 '18 at 9:52

Stephan T.

1,2821921

var array = [{

    id: "4bf58dd8d48988d110941735",

    name: "italy"

  },

  {

    id: "4bf58dd8d48988d1c6941735",

    name: "skandi"

  }, {

    id: "4bf58dd8d48988d147941735",

    name: "diner"

  }, {

    id: "4bf58dd8d48988d110941735",

    name: "italy"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }, {

    id: "4bf58dd8d48988d14a941735",

    name: "vietnam"

  }, {

    id: "4bf58dd8d48988d14a941735",

    name: "fish"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }

];



// you can access the array with arrayAssociative[id], where the id is the real id like "4bf58dd8d48988d110941735"

var arrayAssociative = {};

for (item in array) {

  // first get the unique id's

  var addedNode = arrayAssociative[array[item].id] = arrayAssociative[array[item].id] || {};

  if (addedNode.names == null)

    addedNode.names = {};

  // now get the unique names

  var addedName = arrayAssociative[array[item].id].names[array[item].name] = arrayAssociative[array[item].id].names[array[item].name] || {};

}

console.log(arrayAssociative);

I don't know the exact reason, why the line

var element = arrayAssociative[id] =arrayAssociative[id] || {};

works for this, but let's just accept the funcitonality as it is :)

var array = [{

    id: "4bf58dd8d48988d110941735",

    name: "italy"

  },

  {

    id: "4bf58dd8d48988d1c6941735",

    name: "skandi"

  }, {

    id: "4bf58dd8d48988d147941735",

    name: "diner"

  }, {

    id: "4bf58dd8d48988d110941735",

    name: "italy"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }, {

    id: "4bf58dd8d48988d14a941735",

    name: "vietnam"

  }, {

    id: "4bf58dd8d48988d14a941735",

    name: "fish"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }

];



// you can access the array with arrayAssociative[id], where the id is the real id like "4bf58dd8d48988d110941735"

var arrayAssociative = {};

for (item in array) {

  // first get the unique id's

  var addedNode = arrayAssociative[array[item].id] = arrayAssociative[array[item].id] || {};

  if (addedNode.names == null)

    addedNode.names = {};

  // now get the unique names

  var addedName = arrayAssociative[array[item].id].names[array[item].name] = arrayAssociative[array[item].id].names[array[item].name] || {};

}

console.log(arrayAssociative);

var array = [{

    id: "4bf58dd8d48988d110941735",

    name: "italy"

  },

  {

    id: "4bf58dd8d48988d1c6941735",

    name: "skandi"

  }, {

    id: "4bf58dd8d48988d147941735",

    name: "diner"

  }, {

    id: "4bf58dd8d48988d110941735",

    name: "italy"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }, {

    id: "4bf58dd8d48988d14a941735",

    name: "vietnam"

  }, {

    id: "4bf58dd8d48988d14a941735",

    name: "fish"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }, {

    id: "4bf58dd8d48988d1c4941735",

    name: "resto"

  }

];



// you can access the array with arrayAssociative[id], where the id is the real id like "4bf58dd8d48988d110941735"

var arrayAssociative = {};

for (item in array) {

  // first get the unique id's

  var addedNode = arrayAssociative[array[item].id] = arrayAssociative[array[item].id] || {};

  if (addedNode.names == null)

    addedNode.names = {};

  // now get the unique names

  var addedName = arrayAssociative[array[item].id].names[array[item].name] = arrayAssociative[array[item].id].names[array[item].name] || {};

}

console.log(arrayAssociative);

edited Dec 21 '18 at 10:00

answered Dec 21 '18 at 9:52

Stephan T.

1,2821921

edited Dec 21 '18 at 10:00

answered Dec 21 '18 at 9:52

Stephan T.

1,2821921

answered Dec 21 '18 at 9:52

Stephan T.

1,2821921

answered Dec 21 '18 at 9:52

Stephan T.

1,2821921

1

arrayAssociative[array[item].id] || {} this line gives value in left of || if it is not null/undefined/0/false or value in the right if opposit - stackoverflow.com/q/2100758/860099

– Kamil Kiełczewski
Dec 21 '18 at 10:03

thanks for the explanation <3

– Stephan T.
Dec 21 '18 at 10:05

add a comment |

1

arrayAssociative[array[item].id] || {} this line gives value in left of || if it is not null/undefined/0/false or value in the right if opposit - stackoverflow.com/q/2100758/860099

– Kamil Kiełczewski
Dec 21 '18 at 10:03

thanks for the explanation <3

– Stephan T.
Dec 21 '18 at 10:05

arrayAssociative[array[item].id] || {} this line gives value in left of || if it is not null/undefined/0/false or value in the right if opposit - stackoverflow.com/q/2100758/860099

– Kamil Kiełczewski
Dec 21 '18 at 10:03

thanks for the explanation <3

– Stephan T.
Dec 21 '18 at 10:05

add a comment |

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