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Function: nullsLast()

nullsLast<T>(comparator): Comparator<Nullable<T>>

Defined in: compare/combinators/index.ts:166

Wraps a comparator to place null/undefined values last.

When comparing two null/undefined values, they are considered equal. When comparing null/undefined with a non-null value, null comes last.

Type Parameters​

T​

T

Parameters​

comparator​

Comparator<Nullable<T>>

The comparator for non-null values

Returns​

Comparator<Nullable<T>>

A comparator that places nulls last

Example​

interface Product {
  name: string
  discount: number | null
}

const products = [
  { name: 'Keyboard', discount: 10 },
  { name: 'Mouse', discount: null },
  { name: 'Monitor', discount: 20 },
  { name: 'Webcam', discount: null }
]

// Sort by discount descending, nulls last
products.sort(nullsLast(descending(p => p.discount ?? 0)))
// => [{ name: 'Monitor', discount: 20 },
//     { name: 'Keyboard', discount: 10 },
//     { name: 'Mouse', discount: null },
//     { name: 'Webcam', discount: null }]

See​

nullsFirst - to place nulls at the beginning