JavaScript sort dates with a custom boolean value

Question

I have an array of objects, these objects contains dates and one of them contains an

noDate: true

value. I would like to sort these dates, current I am able to sort them like this:

data.sort((a, b) => a.date - b.date)

But I need to sort them so the object with the noDate true value becomes the first one in the array. I tried this, but it does not work properly:

data.sort((a, b) => a.noDate === true ? -1 : a.date - b.date)

Answer 1

You could take the boolean/ undefined value and take the delta by converting the value to a negated boolean value first. Then sort by date .

 const data = [ { id: 0, noDate: true }, { id: 1, date: new Date('2021-10-30') }, { id: 2, date: new Date('2020-10-30') }, { id: 3, noDate: true }, ]; data.sort((a, b) => !a.noDate - !b.noDate || a.date - b.date); console.log(data); data.sort((a, b) => !b.noDate - !a.noDate || a.date - b.date); console.log(data);

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