Transaction handle scoped to a single commit callback.
Remarks
The only mutation entry-point on the graph. Outside a commit the
graph is read-only; inside a commit reads see staged writes,
outside reads see the previous committed snapshot. There is no
"concurrent mutation" question because there is no concurrent
mutation API — the absence of the construct is what catches the
concurrent-engine-mutations race class. The handle becomes invalid
the moment its callback returns (StaleTxError).
New value, applied atomically with all other
set calls in the same commit. Multiple set calls in one
commit land at the same GraphTime — one transaction creates
exactly one new t, never a fractional moment.
Transaction handle scoped to a single
commitcallback.Remarks
The only mutation entry-point on the graph. Outside a commit the graph is read-only; inside a commit reads see staged writes, outside reads see the previous committed snapshot. There is no "concurrent mutation" question because there is no concurrent mutation API — the absence of the construct is what catches the concurrent-engine-mutations race class. The handle becomes invalid the moment its callback returns (StaleTxError).