Two tests, one column

Two tests, one column

The first 8 steps of a document listing over rows 476 to 489 — the rows of a 4-character pattern in a collection of 8 documents. At each step the range minimum returns a position; the published method compares the chain entry there against the start of the range, and this one asks whether the document at that position is already in the answer. The two columns are the same column, at every step and on every collection tried. The chain is therefore not read — and once it is not read it does not have to be stored, because the structure over it keeps the shape of an array and not its numbers.

Drawn at 700 × 476, wide on the page. Everything above is what chainless-listing returns with no arguments; the caption is the generator's own, computed from the numbers in the drawing rather than written beside it.

6 essays call chainless-listing. The drawing above is what it returns with no arguments at all; every call below passes it something, because a placement that passes nothing draws whichever member of the family the generator happens to default to rather than the one its essay argues about — which is what optcheck and figfill exist to catch.