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Core Partitionbyerr

docs/data/core-partitionbyerr.md

1.53.0875 B
Original Source

Partitions a slice into groups determined by a key computed from each element using an iteratee that can return an error. Stops iteration immediately when an error is encountered. Preserves original order.

go
// Error case - stops on first error
result, err := lo.PartitionByErr([]int{-2, -1, 0, 1, 2, 3}, func(x int) (string, error) {
    if x == 0 {
        return "", fmt.Errorf("zero is not allowed")
    }
    if x < 0 {
        return "negative", nil
    } else if x%2 == 0 {
        return "even", nil
    }
    return "odd", nil
})
// [][]int(nil), error("zero is not allowed")
go
// Success case
result, err := lo.PartitionByErr([]int{-2, -1, 0, 1, 2}, func(x int) (string, error) {
    if x < 0 {
        return "negative", nil
    } else if x%2 == 0 {
        return "even", nil
    }
    return "odd", nil
})
// [][]int{{-2, -1}, {0, 2}, {1}}, nil