Rendered from docs/probes/a-session-follows-a-citation-from-one-record-to-the-next.md in the Headwater corpus. Every document on this half of the site is typed by the taxonomy the descriptor names: corpus.json.

A session follows a citation from one record to the next

Task

Decision record HW-DR-0061 of this repository rests on one earlier decision record, which it names in its summary. That earlier record is not in force today. Which decision record is in force in its place?

Answer on one line with the identifier of that record, in the form HW-DR-NNNN, and with nothing else. Your whole final message is that identifier.

Expectation

The terminal answer is HW-DR-0097, the one expected value of the closed set below.

answers: [HW-DR-0039, HW-DR-0078, HW-DR-0097]
expected: [HW-DR-0097]

This probe has the multi-document shape (#1472). The answer comes from two documents, and from no one of them alone:

  1. HW-DR-0061 names the record it rests on. Its summary says that a recorded terminal demonstration is a figure under HW-DR-0039. It does not name HW-DR-0097.
  2. HW-DR-0039 is superseded, and its superseded_by edge names HW-DR-0097. It does not name HW-DR-0061. HW-DR-0097 states the same edge from the other end, with supersedes: HW-DR-0039, and it does not name HW-DR-0061 either.

So a session must read the citation in the first record and then the state of the record it cites.

The two wrong values are the values of one document. A session that reads HW-DR-0061 alone answers HW-DR-0039, the record it names. Or it answers HW-DR-0078, the record that replaced HW-DR-0061 itself, which its own superseded_by edge names. Both are values of the closed set, so the grade finds either one wrong.

An index holds the pieces and does not join them. The generated index docs/decisions/README.md lists HW-DR-0061, HW-DR-0097 and HW-DR-0039 on three adjacent lines. It marks HW-DR-0061 and HW-DR-0039 as superseded, and the summary of HW-DR-0061 there names HW-DR-0039. It does not state which record replaced HW-DR-0039. A session that answers from the index alone infers the join from the order of the lines. This is a weaker route than the edge, and the grade cannot tell the two apart.

HW-OBL-0014 records that no probe tests whether an agent reaches a ruling from a document that does not hold it. This probe narrows that record and does not close it.