datatype.go

@@ -92,7 +92,7 @@ func checkColumns(s nodeScope) error {
 		if !ok || !t.record {
 			return nil
 		}
-		for _, name := range recordColumns(t) {
+		for _, name := range sortedNames(t.fields) {
 			if err := check(path, name, t.fields[name]); err != nil {
 				return err
 			}

drawfence.go

@@ -88,7 +88,7 @@ func (c *drawCheck) checkRecordDraws(path string, n node) error {
 		return nil
 	}
 	// A record-only template's format renders nothing, so weigh the columns, not the format.
-	columns := recordColumns(t)
+	columns := sortedNames(t.fields)
 	reads := false
 	for _, name := range columns {
 		reads = reads || c.readsPath(t.fields[name])
@@ -148,7 +148,7 @@ func readsTable(n node, a arm) bool {
 	if !isTemplate {
 		return false
 	}
-	_, isTable := t.fields[a.key].(*table)
+	_, isTable := t.head(a.key).(*table)
 	return isTable
 }
 
@@ -248,7 +248,7 @@ func (w *drawWalk) walk(n node, at drawAt) {
 // pins entered, so a selected row renders only its own cells.
 func (w *drawWalk) edge(from node, e renderEdge, at drawAt) {
 	if a, reads := refRead(from, e.label); reads {
-		tr := tableReadOf(from.(*template).fields[a.key], a, e.to)
+		tr := tableReadOf(from.(*template).head(a.key), a, e.to)
 		if k := (readKey{at.group, a.path, at.alt.key()}); !w.read[k] {
 			w.read[k] = true
 			w.reads = append(w.reads, pathRead{at, a, tr})

family.go

@@ -212,7 +212,7 @@ func checkOwnFamily(t *template) error {
 		seen[n] = true
 		for _, e := range renderEdges(n) {
 			if a, isRef := refRead(n, e.label); isRef {
-				if head, isTable := n.(*template).fields[a.key].(*table); isTable && head.family() == own.family() {
+				if head, isTable := n.(*template).head(a.key).(*table); isTable && head.family() == own.family() {
 					return e, head, true
 				}
 			}

fejkdata.go

@@ -146,9 +146,6 @@ func paths(n node) []string {
 	case *template:
 		out := []string{""}
 		for _, name := range sortedNames(n.fields) {
-			if isRef(name) { // a binding, not a path segment
-				continue
-			}
 			for _, p := range paths(n.fields[name]) {
 				out = append(out, join(name, p))
 			}

graph.go

@@ -78,14 +78,9 @@ func contained(n node) []namedNode {
 	}
 }
 
-// named skips a bound {/path} key: it is a render edge, not containment, so using
-// it as a path segment would report a node under a path that does not reach it.
 func named(m map[string]node) []namedNode {
 	out := make([]namedNode, 0, len(m))
 	for _, name := range sortedNames(m) {
-		if isRef(name) {
-			continue
-		}
 		out = append(out, namedNode{name: name, node: m[name]})
 	}
 	return out
@@ -134,8 +129,8 @@ func renderEdges(n node) []renderEdge {
 		var es []renderEdge
 		add := func(name, operand string) {
 			a := splitArm(name, n.refs)
-			c, ok := n.fields[a.key]
-			if !ok {
+			c := n.head(a.key)
+			if c == nil {
 				return
 			}
 			for _, leaf := range pathLeaves(c, a.tail) {

hold.go

@@ -21,7 +21,7 @@ type draw struct {
 }
 
 // readField renders one arm of a token. An arm's key is a sibling field or a
-// reference linkRefs bound into fields. A name the expansion holds — a level some
+// reference linkRefs bound into refHeads. A name the expansion holds — a level some
 // token addresses by dotted path, or a field an operand reads — is drawn once and
 // kept, so {place.postal-code} and {place.locality} read one row, either read twice
 // gives one value, and a shown operand is the operand computed. Every other name is
@@ -32,13 +32,13 @@ func readField(s *session, t *template, held *hold, sc renderScope, a arm) draw
 		if len(a.tail) > 0 {
 			panic(fmt.Sprintf("fejkdata: %q reads a path into %q, which the expansion does not hold", a.name, a.key))
 		}
-		return draw{text: render(s, t.fields[a.key], sc)}
+		return draw{text: render(s, t.head(a.key), sc)}
 	}
 	d := readHold(held, sc, a)
 	if r, done := d.value[a.path]; done {
 		return r
 	}
-	leaf, err := walkPath(t.fields[a.key], a.tail, pathWalk{pins: &d.pins, draws: &pathDraws{s: s, held: d, a: &a}})
+	leaf, err := walkPath(t.head(a.key), a.tail, pathWalk{pins: &d.pins, draws: &pathDraws{s: s, held: d, a: &a}})
 	if err != nil {
 		panic(fmt.Sprintf("fejkdata: %q: %v; a fence should have refused this at New", a.name, err))
 	}

holdfence.go

@@ -52,12 +52,12 @@ func heldHeads(t *template) []string {
 func heldNodes(t *template, head string, readers []reader) map[node]bool {
 	held := map[node]bool{}
 	if _, isPath := t.bound[head]; !isPath {
-		operandDraw(t.fields[head], held)
+		operandDraw(t.head(head), held)
 		return held
 	}
 	for _, r := range readers {
 		if a := splitArm(r.name, t.refs); a.key == head {
-			coverPath(t.fields[head], a.tail, held)
+			coverPath(t.head(head), a.tail, held)
 		}
 	}
 	return held

node.go

@@ -49,7 +49,7 @@ func (*null) isNode() {}
 type template struct {
 	// Filled by `compileString`, `compileTemplate` and `table.compileWhole`:
 	format     string
-	fields     map[string]node // `linkTemplateRefs` adds each bound reference here
+	fields     map[string]node
 	repeat     int
 	separator  string
 	datatype   DataType
@@ -78,19 +78,19 @@ type template struct {
 
 	// Filled by `linkTemplateRefs` and `keyDrawGroup`, from the assembled tree:
 	refs         map[string]refBinding // each reference the format reads -> what it is bound to
+	refHeads     map[string]node       // each refBinding.key -> the category it names
 	readsColumn  *columnRead           // set when the format is one reference alone reading a record's column
 	drawGroupKey string                // its draw group keyed by its category: what a render reads its reference paths under
 }
 
 func (*template) isNode() {}
 
-// field is the node a path segment names; a binding is a render edge, not a field.
-func (t *template) field(seg string) (node, bool) {
-	if isRef(seg) {
-		return nil, false
+// head is the node an arm's key names: a sibling field, or a reference's category.
+func (t *template) head(key string) node {
+	if isRef(key) {
+		return t.refHeads[key]
 	}
-	n, ok := t.fields[seg]
-	return n, ok
+	return t.fields[key]
 }
 
 // compile converts parsed JSON — a category or an inline template — into a node tree,
@@ -277,8 +277,6 @@ func compileChoice(items []any, pos position) (node, error) {
 		}
 		c.cum = cum
 	}
-	// Computed before linkRefs binds references into the items: a binding is keyed
-	// by a reference sigil, which paths skips, so the set is the same after.
 	c.shared = sharedPaths(c.items)
 	return c, nil
 }

path.go

@@ -177,7 +177,7 @@ func walkPath(n node, tail []string, w pathWalk) (node, error) {
 				return nil, err
 			}
 		}
-		child, ok := n.field(tail[0])
+		child, ok := n.fields[tail[0]]
 		if !ok {
 			return nil, fmt.Errorf("no field %q", tail[0])
 		}

record.go

@@ -245,7 +245,7 @@ func recordOf(n node) (*template, []Column, error) {
 	if !ok {
 		return nil, nil, errors.New("names a choice, not a template; a record is a template whose fields are its columns")
 	}
-	names := recordColumns(t)
+	names := sortedNames(t.fields)
 	if len(names) == 0 {
 		return nil, nil, ErrNoColumns
 	}
@@ -274,16 +274,3 @@ func renderRecord(s *session, t *template, columns []Column, sc renderScope) *Re
 	}
 	return r
 }
-
-// recordColumns is the sorted non-reference field names — the columns a record
-// projects. A {/path} binding is carried in fields under its root path, so only a
-// name that is not a reference is a column.
-func recordColumns(t *template) []string {
-	var names []string
-	for _, name := range sortedNames(t.fields) {
-		if !isRef(name) {
-			names = append(names, name)
-		}
-	}
-	return names
-}

reference.go

@@ -68,7 +68,7 @@ func refSegments(name string, folder []string) ([]string, error) {
 }
 
 // linkRefs resolves every reference in the assembled tree. The head of the path —
-// up to the category it names — is bound into the referring template's fields
+// up to the category it names — is bound into the referring template's refHeads
 // under its root path, and the rest reads into it the way a sibling path does, so
 // a reference is held like a sibling and two spellings of one target are one
 // draw. It runs once, after all data is merged, so a reference sees the final
@@ -91,10 +91,8 @@ func linkTemplateRefs(folder []string, path, category string, t *template, root
 	if len(names) == 0 {
 		return nil
 	}
-	if t.fields == nil {
-		t.fields = map[string]node{}
-	}
 	t.refs = make(map[string]refBinding, len(names))
+	t.refHeads = make(map[string]node, len(names))
 	for _, name := range names {
 		segments, err := refSegments(name, folder)
 		if err != nil {
@@ -111,7 +109,7 @@ func linkTemplateRefs(folder []string, path, category string, t *template, root
 		if err := checkPath(target, tail, key); err != nil {
 			return fmt.Errorf("%s: reference {%s}: %w", path, name, err)
 		}
-		t.fields[key] = target
+		t.refHeads[key] = target
 		t.refs[name] = refBinding{key, tail}
 	}
 	if err := t.compileFormat(); err != nil {
@@ -134,7 +132,7 @@ func columnReadOf(t *template) *columnRead {
 		return nil
 	}
 	a := splitArm(name, t.refs)
-	target, isTemplate := t.fields[a.key].(*template)
+	target, isTemplate := t.head(a.key).(*template)
 	if !isTemplate || !target.record || len(a.tail) != 1 {
 		return nil
 	}

todo.md

@@ -19,8 +19,6 @@ Self-sufficiency 5.6), every seat capped by Locality or Self-sufficiency.
 
 This round, in order:
 
-- Keep reference bindings out of `template.fields`, so no walk over a template's fields
-  needs the `isRef` filter `named`, `paths`, `recordColumns` and `template.field` carry.
 - Compile a template's format once: `compileFormat` runs again from `linkTemplateRefs`,
   so `ops`, `bound` and `held` are provisional until linking and its fences run twice.
 - Parse a format once and have the fences read `t.ops`: `eachToken` rescans the format

value.go

@@ -158,7 +158,7 @@ func (p *valueProof) template(t *template) proven {
 	case !isFunc:
 		var leaves []node
 		for _, a := range splitArms(body, t.refs) {
-			leaves = append(leaves, pathLeaves(t.fields[a.key], a.tail)...)
+			leaves = append(leaves, pathLeaves(t.head(a.key), a.tail)...)
 		}
 		return p.unite(leaves)
 	case name == "calc":