hasDuplicatesBy

Checks if an array contains duplicate values based on a custom comparison function.

Usage

import { hasDuplicatesBy } from 'rattail'

hasDuplicatesBy([{ id: 1 }, { id: 2 }, { id: 1 }], (a, b) => a.id === b.id) // true
hasDuplicatesBy([{ id: 1 }, { id: 2 }], (a, b) => a.id === b.id) // false

Arguments

Arg	Type	Defaults
arr	Array
fn	(a, b) => any

Return

Type
boolean

Notes

• Returns true if any two values are considered equal by the comparison function.
• Useful for checking duplicates in arrays of objects or with custom logic.