Code reviewHardcr-g294

Subject Unnecessary allocationLevel Senior–Staff~20 minCommon in Code quality & review interviewsIndustries Software development

Question

Review this Go function that builds a slice of ids from a large result set. It shows up high in allocation profiles.

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Separate real bugs from style. Rank issues by severity, point at the root cause rather than the symptom, and suggest a concrete fix — specific and kind.

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Code to reviewgo

1func collectIDs(rows []Row) []int64 {2    var ids []int643    for _, r := range rows {4        ids = append(ids, r.ID)5    }6    return ids7}

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