How to merge and return new array from object in es6
10
Suppose there are two objects.
const a = [
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' }
]
const b = ['1-1', '1-2', '2-1']
and the result
{
'1-1':[
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
],
'1-2':[
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
],
'2-1':[
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' },
]
}
Basically, I want to group the data.
I use includes to check if the item from b to match the id from a. Then construct the new array.
This is my attempt(fiddle):
return b.map(item => a.map(jtem => {
if(jtem.id.includes(item)){
return {
[item]: jtem
}
}
}))
For somehow, it doesn't work.
and, is there a clever way to avoid the nested for loop or map function?
javascript ecmascript-6 ecmascript-7
asked Mar 25 at 7:01
SPGSPG
2,437103359
add a comment |
10
Suppose there are two objects.
const a = [
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' }
]
const b = ['1-1', '1-2', '2-1']
and the result
{
'1-1':[
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
],
'1-2':[
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
],
'2-1':[
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' },
]
}
Basically, I want to group the data.
I use includes to check if the item from b to match the id from a. Then construct the new array.
This is my attempt(fiddle):
return b.map(item => a.map(jtem => {
if(jtem.id.includes(item)){
return {
[item]: jtem
}
}
}))
For somehow, it doesn't work.
and, is there a clever way to avoid the nested for loop or map function?
javascript ecmascript-6 ecmascript-7
asked Mar 25 at 7:01
SPGSPG
2,437103359
Shouldn't the result be an object?
– Jack Bashford
Mar 25 at 7:02
@JackBashford Hey man, sry, u r right, I just updated it.
– SPG
Mar 25 at 7:08
Do you really wantincludes? I'd recommendstartsWith
– Bergi
Mar 25 at 8:26
@Bergi thx, I thinkstartWithis better
– SPG
Mar 26 at 0:30
add a comment |
10
10
10
1
Suppose there are two objects.
const a = [
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' }
]
const b = ['1-1', '1-2', '2-1']
and the result
{
'1-1':[
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
],
'1-2':[
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
],
'2-1':[
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' },
]
}
Basically, I want to group the data.
I use includes to check if the item from b to match the id from a. Then construct the new array.
This is my attempt(fiddle):
return b.map(item => a.map(jtem => {
if(jtem.id.includes(item)){
return {
[item]: jtem
}
}
}))
For somehow, it doesn't work.
and, is there a clever way to avoid the nested for loop or map function?
javascript ecmascript-6 ecmascript-7
asked Mar 25 at 7:01
SPGSPG
2,437103359
Suppose there are two objects.
const a = [
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' }
]
const b = ['1-1', '1-2', '2-1']
and the result
{
'1-1':[
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
],
'1-2':[
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
],
'2-1':[
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' },
]
}
Basically, I want to group the data.
I use includes to check if the item from b to match the id from a. Then construct the new array.
This is my attempt(fiddle):
return b.map(item => a.map(jtem => {
if(jtem.id.includes(item)){
return {
[item]: jtem
}
}
}))
For somehow, it doesn't work.
and, is there a clever way to avoid the nested for loop or map function?
javascript ecmascript-6 ecmascript-7
javascript ecmascript-6 ecmascript-7
asked Mar 25 at 7:01
SPGSPG
2,437103359
asked Mar 25 at 7:01
SPGSPG
2,437103359
edited Mar 25 at 7:04
SPG
asked Mar 25 at 7:01
SPGSPG
2,437103359
asked Mar 25 at 7:01
SPGSPG
2,437103359
asked Mar 25 at 7:01
SPGSPG
2,437103359
2,437103359
Shouldn't the result be an object?
– Jack Bashford
Mar 25 at 7:02
@JackBashford Hey man, sry, u r right, I just updated it.
– SPG
Mar 25 at 7:08
Do you really wantincludes? I'd recommendstartsWith
– Bergi
Mar 25 at 8:26
@Bergi thx, I thinkstartWithis better
– SPG
Mar 26 at 0:30
add a comment |
Shouldn't the result be an object?
– Jack Bashford
Mar 25 at 7:02
@JackBashford Hey man, sry, u r right, I just updated it.
– SPG
Mar 25 at 7:08
Do you really wantincludes? I'd recommendstartsWith
– Bergi
Mar 25 at 8:26
@Bergi thx, I thinkstartWithis better
– SPG
Mar 26 at 0:30
Shouldn't the result be an object?
– Jack Bashford
Mar 25 at 7:02
Shouldn't the result be an object?
– Jack Bashford
Mar 25 at 7:02
@JackBashford Hey man, sry, u r right, I just updated it.
– SPG
Mar 25 at 7:08
@JackBashford Hey man, sry, u r right, I just updated it.
– SPG
Mar 25 at 7:08
Do you really want
includes? I'd recommend startsWith– Bergi
Mar 25 at 8:26
Do you really want
includes? I'd recommend startsWith– Bergi
Mar 25 at 8:26
@Bergi thx, I think
startWith is better– SPG
Mar 26 at 0:30
@Bergi thx, I think
startWith is better– SPG
Mar 26 at 0:30
add a comment |
1 Answer
1
active
oldest
votes
13
You can do that in following steps:
Apply
reduce()on the arraybDuring each iteration use
filter()on the the arraya- Get all the items from
awhich starts with item ofbusingString.prototype.startsWith()
- At last set it as property of the
acand returnac
const a = [
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' }
]
const b = ['1-1', '1-2', '2-1']
let res = b.reduce((ac,b) => {
ac[b] = a.filter(x => x.id.startsWith(b));
return ac;
},{})
console.log(res)As suggested by @Falco is the comments that It would be better to scan over the a once as its large. So here is that version.Actually its better regarding performance
const a = [
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' }
]
const b = ['1-1', '1-2', '2-1']
let res = a.reduce((ac,x) => {
let temp = b.find(y => x.id.startsWith(y))
if(!ac[temp]) ac[temp] = ;
ac[temp].push(x);
return ac;
},{})
console.log(res)Note: startsWith is not supported by I.E. So you can create polyfill using indexOf
if(!String.prototype.startWith){
String.prototype.startsWith = function(str){
return this.indexOf(str) === 0
}
}answered Mar 25 at 7:04
Maheer AliMaheer Ali
8,206720
1
While it is specifically said in the question that the op wants to use es6, and that IE don't support es6 features, I just want to mention that startsWith() don't work in IE (while reduce, filter, and setting a property of an object is totally fine if IE > 9) and if someone wants to do the same thing that startsWith do, they can implment their own with some substring :)
– Neyt
Mar 25 at 10:07
For bigaand smallbI would probably go witha.reduce(...)because of locality and only scan over the big array once.
– Falco
Mar 25 at 11:13
@Falco Thanks for suggestion I updated.
– Maheer Ali
Mar 25 at 11:30
1
@Neyt Thanks for suggestion I updated
– Maheer Ali
Mar 25 at 11:33
@MaheerAli Thank you - here is a benchmark comparing the two :-) jsbench.me/dfjtoadysr/1
– Falco
Mar 25 at 11:47
add a comment |
Your Answer
StackExchange.ifUsing("editor", function () {
StackExchange.using("externalEditor", function () {
StackExchange.using("snippets", function () {
StackExchange.snippets.init();
});
});
}, "code-snippets");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
draft saved
draft discarded
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f55332644%2fhow-to-merge-and-return-new-array-from-object-in-es6%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
13
You can do that in following steps:
Apply
reduce()on the arraybDuring each iteration use
filter()on the the arraya- Get all the items from
awhich starts with item ofbusingString.prototype.startsWith()
- At last set it as property of the
acand returnac
const a = [
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' }
]
const b = ['1-1', '1-2', '2-1']
let res = b.reduce((ac,b) => {
ac[b] = a.filter(x => x.id.startsWith(b));
return ac;
},{})
console.log(res)As suggested by @Falco is the comments that It would be better to scan over the a once as its large. So here is that version.Actually its better regarding performance
const a = [
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' }
]
const b = ['1-1', '1-2', '2-1']
let res = a.reduce((ac,x) => {
let temp = b.find(y => x.id.startsWith(y))
if(!ac[temp]) ac[temp] = ;
ac[temp].push(x);
return ac;
},{})
console.log(res)Note: startsWith is not supported by I.E. So you can create polyfill using indexOf
if(!String.prototype.startWith){
String.prototype.startsWith = function(str){
return this.indexOf(str) === 0
}
}answered Mar 25 at 7:04
Maheer AliMaheer Ali
8,206720
1
While it is specifically said in the question that the op wants to use es6, and that IE don't support es6 features, I just want to mention that startsWith() don't work in IE (while reduce, filter, and setting a property of an object is totally fine if IE > 9) and if someone wants to do the same thing that startsWith do, they can implment their own with some substring :)
– Neyt
Mar 25 at 10:07
For bigaand smallbI would probably go witha.reduce(...)because of locality and only scan over the big array once.
– Falco
Mar 25 at 11:13
@Falco Thanks for suggestion I updated.
– Maheer Ali
Mar 25 at 11:30
1
@Neyt Thanks for suggestion I updated
– Maheer Ali
Mar 25 at 11:33
@MaheerAli Thank you - here is a benchmark comparing the two :-) jsbench.me/dfjtoadysr/1
– Falco
Mar 25 at 11:47
add a comment |
13
You can do that in following steps:
Apply
reduce()on the arraybDuring each iteration use
filter()on the the arraya- Get all the items from
awhich starts with item ofbusingString.prototype.startsWith()
- At last set it as property of the
acand returnac
const a = [
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' }
]
const b = ['1-1', '1-2', '2-1']
let res = b.reduce((ac,b) => {
ac[b] = a.filter(x => x.id.startsWith(b));
return ac;
},{})
console.log(res)As suggested by @Falco is the comments that It would be better to scan over the a once as its large. So here is that version.Actually its better regarding performance
const a = [
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' }
]
const b = ['1-1', '1-2', '2-1']
let res = a.reduce((ac,x) => {
let temp = b.find(y => x.id.startsWith(y))
if(!ac[temp]) ac[temp] = ;
ac[temp].push(x);
return ac;
},{})
console.log(res)Note: startsWith is not supported by I.E. So you can create polyfill using indexOf
if(!String.prototype.startWith){
String.prototype.startsWith = function(str){
return this.indexOf(str) === 0
}
}answered Mar 25 at 7:04
Maheer AliMaheer Ali
8,206720
1
While it is specifically said in the question that the op wants to use es6, and that IE don't support es6 features, I just want to mention that startsWith() don't work in IE (while reduce, filter, and setting a property of an object is totally fine if IE > 9) and if someone wants to do the same thing that startsWith do, they can implment their own with some substring :)
– Neyt
Mar 25 at 10:07
For bigaand smallbI would probably go witha.reduce(...)because of locality and only scan over the big array once.
– Falco
Mar 25 at 11:13
@Falco Thanks for suggestion I updated.
– Maheer Ali
Mar 25 at 11:30
1
@Neyt Thanks for suggestion I updated
– Maheer Ali
Mar 25 at 11:33
@MaheerAli Thank you - here is a benchmark comparing the two :-) jsbench.me/dfjtoadysr/1
– Falco
Mar 25 at 11:47
add a comment |
13
13
13
You can do that in following steps:
Apply
reduce()on the arraybDuring each iteration use
filter()on the the arraya- Get all the items from
awhich starts with item ofbusingString.prototype.startsWith()
- At last set it as property of the
acand returnac
const a = [
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' }
]
const b = ['1-1', '1-2', '2-1']
let res = b.reduce((ac,b) => {
ac[b] = a.filter(x => x.id.startsWith(b));
return ac;
},{})
console.log(res)As suggested by @Falco is the comments that It would be better to scan over the a once as its large. So here is that version.Actually its better regarding performance
const a = [
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' }
]
const b = ['1-1', '1-2', '2-1']
let res = a.reduce((ac,x) => {
let temp = b.find(y => x.id.startsWith(y))
if(!ac[temp]) ac[temp] = ;
ac[temp].push(x);
return ac;
},{})
console.log(res)Note: startsWith is not supported by I.E. So you can create polyfill using indexOf
if(!String.prototype.startWith){
String.prototype.startsWith = function(str){
return this.indexOf(str) === 0
}
}answered Mar 25 at 7:04
Maheer AliMaheer Ali
8,206720
You can do that in following steps:
Apply
reduce()on the arraybDuring each iteration use
filter()on the the arraya- Get all the items from
awhich starts with item ofbusingString.prototype.startsWith()
- At last set it as property of the
acand returnac
const a = [
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' }
]
const b = ['1-1', '1-2', '2-1']
let res = b.reduce((ac,b) => {
ac[b] = a.filter(x => x.id.startsWith(b));
return ac;
},{})
console.log(res)As suggested by @Falco is the comments that It would be better to scan over the a once as its large. So here is that version.Actually its better regarding performance
const a = [
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' }
]
const b = ['1-1', '1-2', '2-1']
let res = a.reduce((ac,x) => {
let temp = b.find(y => x.id.startsWith(y))
if(!ac[temp]) ac[temp] = ;
ac[temp].push(x);
return ac;
},{})
console.log(res)Note: startsWith is not supported by I.E. So you can create polyfill using indexOf
if(!String.prototype.startWith){
String.prototype.startsWith = function(str){
return this.indexOf(str) === 0
}
}const a = [
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' }
]
const b = ['1-1', '1-2', '2-1']
let res = b.reduce((ac,b) => {
ac[b] = a.filter(x => x.id.startsWith(b));
return ac;
},{})
console.log(res)const a = [
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' }
]
const b = ['1-1', '1-2', '2-1']
let res = b.reduce((ac,b) => {
ac[b] = a.filter(x => x.id.startsWith(b));
return ac;
},{})
console.log(res)const a = [
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' }
]
const b = ['1-1', '1-2', '2-1']
let res = a.reduce((ac,x) => {
let temp = b.find(y => x.id.startsWith(y))
if(!ac[temp]) ac[temp] = ;
ac[temp].push(x);
return ac;
},{})
console.log(res)const a = [
{ id: '1-1-1', name: 'a111' },
{ id: '1-1-2', name: 'a112' },
{ id: '1-2-1', name: 'a121' },
{ id: '1-2-2', name: 'a122' },
{ id: '2-1-1', name: 'a211' },
{ id: '2-1-2', name: 'a212' }
]
const b = ['1-1', '1-2', '2-1']
let res = a.reduce((ac,x) => {
let temp = b.find(y => x.id.startsWith(y))
if(!ac[temp]) ac[temp] = ;
ac[temp].push(x);
return ac;
},{})
console.log(res)if(!String.prototype.startWith){
String.prototype.startsWith = function(str){
return this.indexOf(str) === 0
}
}if(!String.prototype.startWith){
String.prototype.startsWith = function(str){
return this.indexOf(str) === 0
}
}answered Mar 25 at 7:04
Maheer AliMaheer Ali
8,206720
edited Mar 25 at 15:19
answered Mar 25 at 7:04
Maheer AliMaheer Ali
8,206720
answered Mar 25 at 7:04
Maheer AliMaheer Ali
8,206720
answered Mar 25 at 7:04
Maheer AliMaheer Ali
8,206720
8,206720
1
While it is specifically said in the question that the op wants to use es6, and that IE don't support es6 features, I just want to mention that startsWith() don't work in IE (while reduce, filter, and setting a property of an object is totally fine if IE > 9) and if someone wants to do the same thing that startsWith do, they can implment their own with some substring :)
– Neyt
Mar 25 at 10:07
For bigaand smallbI would probably go witha.reduce(...)because of locality and only scan over the big array once.
– Falco
Mar 25 at 11:13
@Falco Thanks for suggestion I updated.
– Maheer Ali
Mar 25 at 11:30
1
@Neyt Thanks for suggestion I updated
– Maheer Ali
Mar 25 at 11:33
@MaheerAli Thank you - here is a benchmark comparing the two :-) jsbench.me/dfjtoadysr/1
– Falco
Mar 25 at 11:47
add a comment |
1
While it is specifically said in the question that the op wants to use es6, and that IE don't support es6 features, I just want to mention that startsWith() don't work in IE (while reduce, filter, and setting a property of an object is totally fine if IE > 9) and if someone wants to do the same thing that startsWith do, they can implment their own with some substring :)
– Neyt
Mar 25 at 10:07
For bigaand smallbI would probably go witha.reduce(...)because of locality and only scan over the big array once.
– Falco
Mar 25 at 11:13
@Falco Thanks for suggestion I updated.
– Maheer Ali
Mar 25 at 11:30
1
@Neyt Thanks for suggestion I updated
– Maheer Ali
Mar 25 at 11:33
@MaheerAli Thank you - here is a benchmark comparing the two :-) jsbench.me/dfjtoadysr/1
– Falco
Mar 25 at 11:47
1
1
While it is specifically said in the question that the op wants to use es6, and that IE don't support es6 features, I just want to mention that startsWith() don't work in IE (while reduce, filter, and setting a property of an object is totally fine if IE > 9) and if someone wants to do the same thing that startsWith do, they can implment their own with some substring :)
– Neyt
Mar 25 at 10:07
While it is specifically said in the question that the op wants to use es6, and that IE don't support es6 features, I just want to mention that startsWith() don't work in IE (while reduce, filter, and setting a property of an object is totally fine if IE > 9) and if someone wants to do the same thing that startsWith do, they can implment their own with some substring :)
– Neyt
Mar 25 at 10:07
For big
a and small b I would probably go with a.reduce(...) because of locality and only scan over the big array once.– Falco
Mar 25 at 11:13
For big
a and small b I would probably go with a.reduce(...) because of locality and only scan over the big array once.– Falco
Mar 25 at 11:13
@Falco Thanks for suggestion I updated.
– Maheer Ali
Mar 25 at 11:30
@Falco Thanks for suggestion I updated.
– Maheer Ali
Mar 25 at 11:30
1
1
@Neyt Thanks for suggestion I updated
– Maheer Ali
Mar 25 at 11:33
@Neyt Thanks for suggestion I updated
– Maheer Ali
Mar 25 at 11:33
@MaheerAli Thank you - here is a benchmark comparing the two :-) jsbench.me/dfjtoadysr/1
– Falco
Mar 25 at 11:47
@MaheerAli Thank you - here is a benchmark comparing the two :-) jsbench.me/dfjtoadysr/1
– Falco
Mar 25 at 11:47
add a comment |
draft saved
draft discarded
Thanks for contributing an answer to Stack Overflow!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
draft saved
draft discarded
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f55332644%2fhow-to-merge-and-return-new-array-from-object-in-es6%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Shouldn't the result be an object?
– Jack Bashford
Mar 25 at 7:02
@JackBashford Hey man, sry, u r right, I just updated it.
– SPG
Mar 25 at 7:08
Do you really want
includes? I'd recommendstartsWith– Bergi
Mar 25 at 8:26
@Bergi thx, I think
startWithis better– SPG
Mar 26 at 0:30