JavaScript removes objects with the same key value from the object array

topic description

remove objects with the same key value from the object array

sources of topics and their own ideas

related codes 

let arr = [
  {"weight":10,"id":1},
  {"weight":20,"id":2},
  {"weight":30,"id":2},
  {"weight":40,"id":4},
  {"weight":50,"id":5}
];

what result do you expect? What is the error message actually seen? 

let arr = [
  {"weight":10,"id":1},
  {"weight":30,"id":2},
  {"weight":40,"id":4},
  {"weight":50,"id":5}
];
Javascript
Aug.05,2021 
let obj = {}
arr = arr.reduce((item, next) => {
  obj[next.id] ? '' : obj[next.id] = true && item.push(next)
  return item
}, [])
console.log(arr)

use the utility function, lodash uniqBy , 

const arr = [
  {"weight":10,"id":1},
  {"weight":20,"id":2},
  {"weight":30,"id":2},
  {"weight":40,"id":4},
  {"weight":50,"id":5}
]
_.uniqBy(arr, 'id')

if, according to the reference results provided, the data with an id of "2" appears twice and the value of the latter is actually taken, then the above answer is not correct. 

let obj = {}
arr.map(item => {
  obj[item.id] = item
})
let result = Object.values(obj)

Don't forget that the data of the landlord is stored in an array, and the array itself is ordered, while the object key is unordered. So using native object key to remove weight is not the most suitable answer. Here is a possible answer 

[...new Map(arr.map(({id, weight})=>([id, weight]))).entries()].map(([id, weight])=>({id, weight}))

Previous: I wrote a python to download and install the software with one click, but when some programs are installed, I need to judge what to do with Y or N

Next: Could you tell me about the front-end query?

css mysql arrays josn react html typescript webpack npm sass R objective-c .net sql-server jquery python-3.x angularjs django angular excel regex iphone ajax linux xml pandas vba spring database wordpress string wpf xcode windows bash postgresql oracle multithreading eclipse list firebase algorithm macos forms image scala visual-studio azure bootstrap spring-boot react-native python-2.7 docker performance function winforms matlab powershell apache dataframe api sqlite numpy rest shell selenium flutter dart maven loops qt swing android-studio csv express file class tensorflow sorting codeigniter perl
MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1eb1736-2359.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1eb1736-2359.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
Need Help?