Unique values in an array.

uniqueArrays.ts

// Get unique values from an array of primitives

export function unique<T extends any>(arr: T[]) {
  return Array.from(new Set(arr).values())
}

export function uniqueAdjacent<T extends any>(arr: T[]) {
  return arr.filter((t, i) => i === 0 || !(t === arr[i - 1]))
}

// Get unique values from an array of objects (or anything)

export function uniqueObj<T extends any>(arr: T[]) {
  return Array.from(new Map(arr.map((p) => [JSON.stringify(p), p])).values())
}

export function uniqueAdjacentObj<T extends any>(arr: T[]) {
  return arr.filter(
    (t, i) => i === 0 || !(JSON.stringify(t) === JSON.stringify(arr[i - 1]))
  )
}

// Get unique values from an array of arrays

export function uniqueArr<T extends any[]>(arr: T[]) {
  return Array.from(new Map(arr.map((p) => [p.join(), p])).values())
}

export function uniqueAdjacentArr<T extends any[]>(arr: T[]) {
  return arr.filter(
    (t, i) => i === 0 || !t.every((v, j) => v === arr[i - 1][j])
  )
}