Answer stability round 1: readsRow counts a selector, checkNameReads defers to refuseSingleRead, climbed names the child's row, and geo-se.py owns its big-city reading

data-import/geo-se.py

@@ -37,7 +37,7 @@ NVDB_PAGE = 50000
 OUT = Path(__file__).resolve().parent.parent / "data" / "geo" / "SE"
 CACHE = Path(__file__).resolve().parent / "cache"
 TIMEZONE = "Europe/Stockholm"
-# The big cities the delivery-digit rule excepts: docs/research/research-geo-se.md, postnummer Structure.
+# This script's reading of the "exceptions in big cities" in docs/research/research-geo-se.md, postnummer Structure.
 ONE_POSITION = {"Stockholm", "Göteborg", "Malmö"}
 # A tätort's floor: "minst 200 invånare", docs/research/research-geo-se.md, Ortnamn.
 UNMATCHED_POPULATION = 200

namefence.go

@@ -9,8 +9,8 @@ import (
 	"github.com/larvit/fejkdata/internal/invariant"
 )
 
-// checkNameReads refuses each binding of t read only once, a read of a name inside the field bound
-// to it, and a read {n} beside {n.w} where n's pick renders w twice.
+// checkNameReads refuses each binding of t that refuseSingleRead refuses, a read of a name inside
+// the field bound to it, and a read {n} beside {n.w} where n's pick renders w twice.
 func checkNameReads(label string, t *template, names resolvedNames) error {
 	for _, tok := range t.tokens {
 		if tok.Kind != grammar.NameBind {

path.go

@@ -185,8 +185,9 @@ func probePath(n node, tail []string, steps []pathStep) ([]pathStep, error) {
 // For a read through a name, memo keeps the variant drawn at each of levels, so paths sharing a
 // prefix share it. It returns the leaf and the pins its row is in.
 func drawSteps(s *drawstate.State, n node, steps []pathStep, pins *pinSet, memo *drawMemo, levels []pickKey) (node, *pinSet) {
-	// climbed is the table a ".." stepped up to. The next step down from it draws its row afresh,
-	// into pins of its own, which memo shares with every path of the pick stepping down there.
+	// climbed is the table a ".." stepped up to. The next step down from it draws the child's row
+	// afresh, into pins holding only the rows from climbed up, which memo shares with every path
+	// of the pick stepping down there.
 	var climbed *rowsTable
 	for _, st := range steps {
 		if c, ok := n.(*choice); ok {

table.go

@@ -265,13 +265,14 @@ func (t *table) route(tail []string, descended bool) (tableRoute, error) {
 	if err != nil {
 		return tableRoute{}, err
 	}
-	selected, readsRow := sel != "", descended || len(tail) > 0
+	selected := sel != ""
+	readsRow := selected || descended || len(tail) > 0
 	// A selector further down pins this table by ancestry; drawing first could draw a row the
 	// selector is not inside.
 	pinnedBelow := grammar.HasSelector(tail)
 	r := tableRoute{sel: sel, draw: !selected && readsRow && !pinnedBelow}
 	switch {
-	case !selected && !readsRow:
+	case !readsRow:
 		r.next = t
 	case len(tail) == 0:
 		r.next = t.rowNode