Status: IN
`VectorClock.compare` returns exactly one of `BEFORE`, `AFTER`, `EQUAL`, or `CONCURRENT`, implementing the partial order defined by component-wise comparison.
Source: entries/2026/05/29/vector-clocks-vector_clock.md
def compare(self, other):
# Returns "BEFORE", "AFTER", "EQUAL", or "CONCURRENT"
if has_less and has_greater: return "CONCURRENT"
if has_less: return "BEFORE"
if has_greater: return "AFTER"
return "EQUAL"