Find first element of array and show it in map function but have warning - React

Question

I have data like so:

    {
      "title": 0,
      "name": 0,
      "score": 0,
      "summary": [
        {
          "id": 1,
          "start": "2019-11-01",
          "end": "2019-11-04"
        },
        {
          "id": 2,
          "start": "2019-11-01",
          "end": "2019-11-04"
        }
      ]
    }

I am trying to access the first element of summary, so I have tried this:

    const newDate = new Date(data?.summary.map((d: any, index: number) => {
               if (index === 0) {
                 return (
                 new Date(d.start)
               )
          }
     })),

although it's working i get the warning:

Array.prototype.map() expects a value to be returned at the end of arrow function array-callback-return

I know it must be because I am not returning anything in the callback and the return is in the if statement?

Why using map in the first place instead of direct accesss to the array element? — MorKadosh
– MorKadosh, Commented Nov 4, 2021 at 11:58

munleashed · Accepted Answer · 2021-11-04 11:58:50Z

1

if (index === 0) {
                 return (
                 new Date(d.start)
               )

You are only returning a value if index === 0.

Im not sure what are you trying to achieve:

const newDate = new Date(data?.summary.map((d: any, index: number) => {
           if (index === 0) {
             return (
             new Date(d.start)
           )
      }
 })),

I suppose:

const newDate = newDate(data?.summary[0]?.start)

Will do the thing.

edited Nov 4, 2021 at 11:58

answered Nov 4, 2021 at 11:56

munleashed

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3 Comments

Sole Over a year ago

So what would be the workaround?

munleashed Over a year ago

See my updated post. When you are dealing with a single value rather than with an array, you dont need map or any other method of array.

Sole Over a year ago

Over thinking the issue, thanks that did work

Soufiane Boutahlil · Accepted Answer · 2021-11-04 11:58:56Z

1

You can access to the first element without using map function:

const newDate = new Date(data?.summary[0].start)

answered Nov 4, 2021 at 11:58

Soufiane Boutahlil

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1 Comment

Sole Over a year ago

Over thinking the issue, thanks that did work

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