datatype.go

@@ -148,6 +148,7 @@ func columnItems(n node) (items []*template, nullable bool) {
 }
 
 // itemKind is how a column item comes by its datatype: none, read from a typed column, or declared.
+// The kinds are declared from the one that declares least.
 type itemKind int
 
 const (
@@ -156,6 +157,10 @@ const (
 	kindDeclares
 )
 
+func (k itemKind) declaresLess(than itemKind) bool {
+	return k < than
+}
+
 func kindOf(t *template) itemKind {
 	switch {
 	case t.datatype != DataTypeString:
@@ -178,7 +183,7 @@ type itemPair struct {
 // the one that declares least, a when both declare alike.
 func disagreement(a *template, da DataType, b *template, db DataType) error {
 	d := itemPair{first: da, second: db, fix: a, other: b, want: db}
-	if kindOf(b) < kindOf(a) {
+	if kindOf(b).declaresLess(kindOf(a)) {
 		d.fix, d.other, d.want = b, a, da
 	}
 	proven := (&valueProof{}).proveColumnItem(d.fix).not[d.want] == ""

todo.md

@@ -31,8 +31,6 @@ on 2026-09-29 a third time (Navigation 7.0, Locality 5.6, Shape 6.3, Self-suffic
 
 This round, in order:
 
-- Pick `disagreement`'s fix through a named `itemKind` comparison: six seats could not
-  see that the kinds' declaration order is the rule.
 - Give `tableSite` one test for a cell, and have `traceRead` report no row outside a
   table: the zero value reads as row 0, a real cell, so each reader tests `table` first.
 - Rename `ftoken` to `scanUnit`, beside `formatToken`, and `session` to