Answer stability round 1: the tests precede the code they pin, ErrNoColumns's doc speaks of itself alone, the edited docs are reflowed, and the binding hint and a JSON-shaped template's parse position are filed as items 228 and 229

record.go

@@ -209,10 +209,11 @@ func (f *Generator) FakeRecordTemplate(input string) (*Record, error) {
 	return t.Fake(), nil
 }
 
-// ErrNoColumns and errChoiceRecord are the record fences a path can answer, so its entry
-// point names the record to write instead.
+// ErrNoColumns is a record fence a path can answer, so its entry point names the record to
+// write instead.
 var ErrNoColumns = errors.New("has no fields, so no columns")
 
+// errChoiceRecord is the other fence a path can answer.
 var errChoiceRecord = errors.New("names a choice, not a template; a record is a template whose fields are its columns")
 
 // recordOf is the record template n is; settleRecords fixed its columns at load.