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LWW register with Lamport stamps: receive does not advance the local clock · case 03

A write made after receiving a newer value loses to that older value on other replicas.

Member previewVariant 3 · 3 implementations · 8 checks per implementation

Case contract

Each replica holds a register [value, clock, writer] and a Lamport clock, all starting at [None, 0, ""] and 0. ["set", r, v] increments r's clock and stamps v with (clock, r). ["send", s, d] delivers s's register to d: d's clock becomes max(own, incoming clock) and d adopts the incoming register when (clock, writer) is lexicographically larger. Return values and clocks per replica.

Why this case matters

Last-writer-wins registers need total, replica-independent stamp ordering to converge.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
later local write after receive wins	`{"clocks": [2, 1, 0], "values": ["a2", "b1", null]}`	`{"clocks": [3, 3, 0], "values": ["b1", "b1", null]}`	Failed

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