20. A corpus is supplied by the reader, never by the package

Context

Devices and figures are finite and closed: Harsdörffer's rings and Llull's nine letters are the procedure, so they ship with it (ADR 0017). A corpus is neither. It is external, open-ended, and — this is the part that decides the question — usually somebody else's work.

Jean Paul's excerpt books are the case. The manuscripts are public domain: he died in 1825. The transcriptions that make 100,000 entries usable are a scholarly edition from the Arbeitsstelle Jean-Paul-Edition at Würzburg, with named transcribers and their own rights. Freely readable is not freely redistributable.

Decision

The package carries the loader; the reader supplies the reading. Corpus, Entry and a parser live in core; no corpus does. A corpus reaches a procedure through the existing source parameter as text — JSON or one excerpt per line — so nothing new was needed to carry it, and the CLI's --source FILE already works.

Test fixtures are synthetic throughout. The Würzburg sample this chapter was designed against sits outside the repository entirely.

Consequences

ideenwuerfeln works against whatever a reader has, which is the honest arrangement for a procedure whose whole point is drawing on a collection somebody assembled by hand.

Reading the parameter as text rather than a path also means the library never opens a file the caller did not hand it, which keeps the capability surface where it was.

apply may now refuse: a corpus of one line is not three excerpts. The round-trip suite had to learn that a generator declining unusable input is not a failure of the property — what the property asserts is that whatever apply produces passes check.

The reconstruction question is recorded separately. Jean Paul named the notebook but never wrote the rule down, so ideenwuerfeln carries attested: reconstruction — the first row to do so, and the reason ADR 0018 added the field.