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Core Latestbyerr

docs/data/core-latestbyerr.md

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Searches a collection for the element with the maximum time extracted by the predicate. Returns zero value when the collection is empty. Stops iteration immediately when an error is encountered.

go
type Event struct{ At time.Time }
events := []Event{{At: time.Now()}, {At: time.Now().Add(2 * time.Hour)}}
last, err := lo.LatestByErr(events, func(e Event) (time.Time, error) {
    return e.At, nil
})
// Event{At: ...}, nil
go
// Error case - stops on first error
type Event struct{ At time.Time }
events := []Event{{At: time.Now()}, {At: time.Time{}}, {At: time.Now().Add(2 * time.Hour)}}
_, err := lo.LatestByErr(events, func(e Event) (time.Time, error) {
    if e.At.IsZero() {
        return time.Time{}, fmt.Errorf("zero time not allowed")
    }
    return e.At, nil
})
// error("zero time not allowed")