Code reviewHardcr-g268

Subject Boundary conditionsLevel Mid–Senior~18 minCommon in Concurrency interviewsIndustries Software development

Question

Review this Go code that removes expired sessions from a map while iterating.

What a strong answer looks like

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 reap(sessions map[string]Session, now time.Time) int {2    removed := 03    for id, s := range sessions {4        if s.expiresAt.Before(now) {5            delete(sessions, id)6            removed++7        }8        if s.lastSeen.Add(idleTTL).Before(now) {9            sessions[id] = touch(s)   // refresh non-expired idle ones10        }11    }12    return removed13}

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