Merge unique values to array from array of arrays

Question

I have array like this:

[
  [
    {id:1, name:'xxx'}
  ],
  [
    {id:2, name:'xxx'},
    {id:1, name:'xxx'}
  ],
  [
    {id:2, name:'xxx'},
    {id:1, name:'xxx'},
    {id:3, name:'xxx'}
  ]
]

I need pick just objects with unique id and merge them into one array. Each object has id property, so I tried this:

_.(data).union().uniqBy(o => o.id).value()

but it gives me wrong result.

My required output should be like this:

[{id:1, name:'xxx'}, {id:2, name:'xxx'}, {id:3, name:'xxx'}]

Can you help me with that? Thanks.

Answer 1

Use _.flatten() to merge the sub arrays into a single array and then apply _.uniqBy() :

 const data = [[{"id":1,"name":"xxx"}],[{"id":2,"name":"xxx"},{"id":1,"name":"xxx"}],[{"id":2,"name":"xxx"},{"id":1,"name":"xxx"},{"id":3,"name":"xxx"}]]; const result = _(data) .flatten() .uniqBy('id') .value(); console.log(result); 

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