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Core Uniqbyerr

docs/data/core-uniqbyerr.md

1.53.0653 B
Original Source

Returns a duplicate-free version of a slice based on a computed key using an iteratee that can return an error. Stops iteration immediately when an error is encountered. Keeps only the first element for each unique key.

go
// Error case - stops on first error
result, err := lo.UniqByErr([]int{0, 1, 2, 3, 4, 5}, func(i int) (int, error) {
    if i == 3 {
        return 0, fmt.Errorf("number 3 is not allowed")
    }
    return i % 3, nil
})
// []int(nil), error("number 3 is not allowed")
go
// Success case
result, err := lo.UniqByErr([]int{0, 1, 2, 3, 4, 5}, func(i int) (int, error) {
    return i % 3, nil
})
// []int{0, 1, 2}, nil