Rename grammar's NameRead to PathRead and CheckName to CheckIdentifier, so a name in the engine is only a bound name

README.md

@@ -989,7 +989,7 @@ internal/builtinfunc/ the {name()} functions: their checks and draws, checksums,
 internal/datafiles/ the walk of a data tree: its folders, its category files and the rows files beside them
 internal/datatype/ the datatype a record column holds; the root's DataType is an alias of it
 internal/drawstate/ the seeded randomness and the {seq()} counters a generator draws through
-internal/grammar/ how the template language is written: format tokens, paths and selectors, reference sigils, names, calc syntax, and whether an argument is a template or a path
+internal/grammar/ how the template language is written: format tokens, paths and selectors, reference sigils, identifiers, calc syntax, and whether an argument is a template or a path
 internal/invariant/ the one phrase every package panics with when an invariant breaks
 internal/proven/ what a proof knows of a value, and the bounds a calc takes from its operands
 internal/rows/  a table's rows: the TSV, the options proved over it, the links between tables, row selection and draws, and the pin set one path or one named pick fixes

arm.go

@@ -77,7 +77,7 @@ func checkSegments(a arm) error {
 // or a builtin already prepared with its args.
 type op struct {
 	grammar.Token
-	arms []arm // grammar.NameRead: the '|' alternatives, split into head and tail once
+	arms []arm // grammar.PathRead: the '|' alternatives, split into head and tail once
 	call builtinfunc.Call
 	// operands are the fields the builtin reads, in the order its operands func
 	// fixed; expand reads them before the call. nil for a builtin that reads none.

format.go

@@ -60,7 +60,7 @@ func checkToken(t grammar.Token, fields map[string]node) ([]unboundRead, error)
 		return checkReads(t, fields, true)
 	case grammar.NameBind:
 		return nil, checkBind(t, fields)
-	case grammar.NameRead:
+	case grammar.PathRead:
 		unbound, err := checkReads(t, fields, false)
 		if err != nil {
 			return nil, err
@@ -113,7 +113,7 @@ func checkBind(t grammar.Token, fields map[string]node) error {
 	if isOption(name) {
 		return fmt.Errorf("token {%s}: %q is an option and can never be a name; rename it", t.Body, name)
 	}
-	if err := grammar.CheckName(name); err != nil {
+	if err := grammar.CheckIdentifier(name); err != nil {
 		return fmt.Errorf("token {%s}: name %w", t.Body, err)
 	}
 	return nil
@@ -167,7 +167,7 @@ func checkArm(name string, fields map[string]node, wholeToken bool) (missing boo
 // hintableRef reports whether {/name} is a reference the grammar accepts, so the
 // hint never names a spelling that fails too.
 func hintableRef(name string) bool {
-	return grammar.CheckPathNames(name) == nil
+	return grammar.CheckPathIdentifiers(name) == nil
 }
 
 // tokenReads lists the names t reads: a read's arms, or the operands a call's builtin reads.
@@ -214,7 +214,7 @@ func compileFormat(t *template, targets map[*nameBinding]nameTarget) (formatOps,
 		case grammar.BuiltinCall:
 			o.call = builtinfunc.Prep(tok.Fn, tok.Args)
 			o.operands, err = t.compileArms(builtinfunc.Operands(tok.Fn, tok.Args), targets)
-		case grammar.NameRead:
+		case grammar.PathRead:
 			o.arms, err = t.compileArms(tok.Arms, targets)
 		case grammar.NameBind:
 			continue

internal/datafiles/datafiles.go

@@ -115,7 +115,7 @@ func (s Source) walkFolder(dir []string, compile func(Category) error) (bool, er
 	if err != nil || !holds {
 		return false, err
 	}
-	if err := grammar.CheckName(dir[len(dir)-1]); err != nil {
+	if err := grammar.CheckIdentifier(dir[len(dir)-1]); err != nil {
 		return false, fmt.Errorf("%s: folder %w", s.labelled(s.dirPath(dir)), err)
 	}
 	return true, nil
@@ -140,7 +140,7 @@ func (s Source) compileFile(dir []string, file string, rows *rowsFiles, compile
 	}
 	full := path.Join(rows.dir, file)
 	name := strings.TrimSuffix(file, ".json")
-	if err := grammar.CheckName(name); err != nil {
+	if err := grammar.CheckIdentifier(name); err != nil {
 		return false, fmt.Errorf("%s: category %w", s.labelled(full), err)
 	}
 	b, err := fs.ReadFile(s.fsys, full)

internal/grammar/format.go

@@ -66,7 +66,7 @@ type Token struct {
 	Body string   // the braces' content, as written
 	Fn   string   // BuiltinCall
 	Args []string // BuiltinCall
-	Arms []string // NameRead: the '|' alternatives
+	Arms []string // PathRead: the '|' alternatives
 	// NameBind: the reference it binds, and the name.
 	BoundRef, Bound string
 }
@@ -77,7 +77,7 @@ const (
 	BuiltinCall TokenKind = iota + 1
 	LiteralRun
 	NameBind
-	NameRead
+	PathRead
 )
 
 const AsWord = " as "
@@ -104,7 +104,7 @@ func ParseFormat(format string) ([]Token, error) {
 			return nil
 		}
 		if indexOutside(u.body, '(') < 0 {
-			toks = append(toks, Token{Kind: NameRead, Body: u.body, Arms: splitOutside(u.body, '|')})
+			toks = append(toks, Token{Kind: PathRead, Body: u.body, Arms: splitOutside(u.body, '|')})
 			return nil
 		}
 		name, args, ok := FuncCall(u.body)

internal/grammar/format_test.go

@@ -27,7 +27,7 @@ func TestParseFormatReadsEachTokenKind(t *testing.T) {
 	}
 	want := []Token{
 		{Kind: LiteralRun, Lit: "a{"},
-		{Kind: NameRead, Body: "x|/y.z[a.b]", Arms: []string{"x", "/y.z[a.b]"}},
+		{Kind: PathRead, Body: "x|/y.z[a.b]", Arms: []string{"x", "/y.z[a.b]"}},
 		{Kind: NameBind, Body: "/p as q", BoundRef: "/p", Bound: "q"},
 		{Kind: BuiltinCall, Body: "f(1, n)", Fn: "f", Args: []string{"1", "n"}},
 	}

internal/grammar/identifier.go

@@ -5,18 +5,18 @@ import (
 	"strings"
 )
 
-// reservedInName is what a category, folder or field name may not contain: a dot
+// reservedInIdentifier is what an identifier may not contain: a dot
 // separates the segments of a path, '|' the arms of a token, '(' opens a function
 // call, braces delimit the token, '/' starts a reference, and brackets and a quote
-// open a JSON value. A name carrying one is rejected where it is authored rather
+// open a JSON value. An identifier carrying one is rejected where it is authored rather
 // than where it would be unreachable.
-const reservedInName = ".|({}/[]\""
+const reservedInIdentifier = ".|({}/[]\""
 
-var reservedList = strings.Join(strings.Split(reservedInName, ""), " ")
+var reservedList = strings.Join(strings.Split(reservedInIdentifier, ""), " ")
 
-// CheckName rejects a name the dot path, {token} and JSON grammars cannot spell, or a struct
-// tag cannot read.
-func CheckName(name string) error {
+// CheckIdentifier rejects an identifier, the name of a folder, category, field or column, that the
+// dot path, {token} and JSON grammars cannot spell, or a struct tag cannot read.
+func CheckIdentifier(name string) error {
 	if name == "" {
 		return fmt.Errorf("%q is empty, which is not a path segment, so List never offers it", name)
 	}
@@ -26,21 +26,21 @@ func CheckName(name string) error {
 	if strings.Contains(name, AsWord) {
 		return fmt.Errorf("%q contains %q, which a token reads as binding a name; rename it", name, AsWord)
 	}
-	if i := strings.IndexAny(name, reservedInName); i >= 0 {
+	if i := strings.IndexAny(name, reservedInIdentifier); i >= 0 {
 		return fmt.Errorf("%q contains %q; a name may not use %s, which the dot path, {token} and JSON grammars reserve",
 			name, name[i:i+1], reservedList)
 	}
 	return nil
 }
 
-// CheckPathNames rejects a dotted path with a segment no name may be.
-func CheckPathNames(path string) error {
+// CheckPathIdentifiers rejects a dotted path with a segment no identifier may be.
+func CheckPathIdentifiers(path string) error {
 	segs, err := SplitPath(path)
 	if err != nil {
 		return err
 	}
-	for _, seg := range NameSegments(segs) {
-		if err := CheckName(seg); err != nil {
+	for _, seg := range IdentifierSegments(segs) {
+		if err := CheckIdentifier(seg); err != nil {
 			return fmt.Errorf("path %w", err)
 		}
 	}

internal/grammar/identifier_test.go

@@ -0,0 +1,16 @@
+package grammar
+
+import "testing"
+
+func TestCheckIdentifierRefusesWhatAGrammarReserves(t *testing.T) {
+	for _, name := range []string{"", "-", "a as b", "a.b", "a|b", "a(b", "a{b", "a}b", "a/b", "a[b", "a]b", `a"b`} {
+		if CheckIdentifier(name) == nil {
+			t.Errorf("CheckIdentifier(%q) = nil, want an error", name)
+		}
+	}
+	for _, name := range []string{"a", "postal-code", "é", "a_b"} {
+		if err := CheckIdentifier(name); err != nil {
+			t.Errorf("CheckIdentifier(%q) = %v, want nil", name, err)
+		}
+	}
+}

internal/grammar/name_test.go

@@ -1,16 +0,0 @@
-package grammar
-
-import "testing"
-
-func TestCheckNameRefusesWhatAGrammarReserves(t *testing.T) {
-	for _, name := range []string{"", "-", "a as b", "a.b", "a|b", "a(b", "a{b", "a}b", "a/b", "a[b", "a]b", `a"b`} {
-		if CheckName(name) == nil {
-			t.Errorf("CheckName(%q) = nil, want an error", name)
-		}
-	}
-	for _, name := range []string{"a", "postal-code", "é", "a_b"} {
-		if err := CheckName(name); err != nil {
-			t.Errorf("CheckName(%q) = %v, want nil", name, err)
-		}
-	}
-}

internal/grammar/path.go

@@ -150,8 +150,8 @@ func UnspellableInSelector(s string) string {
 	return ""
 }
 
-// NameSegments is the segments of a path that are names, its selectors and ".." left out.
-func NameSegments(segs []string) []string {
+// IdentifierSegments is the segments of a path that are identifiers, its selectors and ".." left out.
+func IdentifierSegments(segs []string) []string {
 	out := segs[:0:0]
 	for _, s := range segs {
 		if !IsSelector(s) && s != ".." {

internal/grammar/path_test.go

@@ -33,9 +33,9 @@ func TestSplitPathRefusesAStraySelectorBracket(t *testing.T) {
 	}
 }
 
-func TestNameSegmentsDropSelectorsAndStepsUp(t *testing.T) {
-	if got := NameSegments([]string{"a", "[b]", "..", "c"}); !reflect.DeepEqual(got, []string{"a", "c"}) {
-		t.Errorf("NameSegments = %q, want [a c]", got)
+func TestIdentifierSegmentsDropSelectorsAndStepsUp(t *testing.T) {
+	if got := IdentifierSegments([]string{"a", "[b]", "..", "c"}); !reflect.DeepEqual(got, []string{"a", "c"}) {
+		t.Errorf("IdentifierSegments = %q, want [a c]", got)
 	}
 }
 

internal/grammar/template.go

@@ -34,7 +34,7 @@ func isJSONStart(arg string) bool {
 
 // pathAdvice refuses a spelling of path, naming path to write, or why no name can spell it.
 func pathAdvice(path, refusal string) error {
-	if err := CheckPathNames(path); err != nil {
+	if err := CheckPathIdentifiers(path); err != nil {
 		return err
 	}
 	return fmt.Errorf("%s; write %s", refusal, path)
@@ -71,7 +71,7 @@ func loneReference(arg string) (string, bool) {
 
 // loneRef is the reference a format of one reference token and nothing else reads.
 func loneRef(toks []Token) (string, bool) {
-	if len(toks) != 1 || toks[0].Kind != NameRead || len(toks[0].Arms) != 1 || !IsRef(toks[0].Arms[0]) {
+	if len(toks) != 1 || toks[0].Kind != PathRead || len(toks[0].Arms) != 1 || !IsRef(toks[0].Arms[0]) {
 		return "", false
 	}
 	return toks[0].Arms[0], true

internal/rows/rows.go

@@ -94,7 +94,7 @@ func (t *Table[O]) parseRows(data string) error {
 	t.header = strings.Split(header, "\t")
 	t.col = make(map[string]int, len(t.header))
 	for i, name := range t.header {
-		if err := grammar.CheckName(name); err != nil {
+		if err := grammar.CheckIdentifier(name); err != nil {
 			return fmt.Errorf("column %w", err)
 		}
 		if _, dup := t.col[name]; dup {

node.go

@@ -381,7 +381,7 @@ func compileFields(m map[string]any, pos position) (map[string]node, error) {
 		if isOption(k) {
 			continue
 		}
-		if err := grammar.CheckName(k); err != nil {
+		if err := grammar.CheckIdentifier(k); err != nil {
 			return nil, fmt.Errorf("field %w", err)
 		}
 		n, err := compileAt(m[k], pos)

record.go

@@ -145,7 +145,7 @@ func (f *Generator) FakeRecord(path string) (*Record, error) {
 	}
 	record, err := recordOf(n)
 	if errors.Is(err, ErrNoColumns) {
-		ns := grammar.NameSegments(segments)
+		ns := grammar.IdentifierSegments(segments)
 		return nil, fmt.Errorf(`fejkdata: %s %w; render it as a column of one: {"format":"","%s":"{/%s}"}`, path, err, ns[len(ns)-1], path)
 	}
 	if err != nil {

render.go

@@ -123,7 +123,7 @@ func expand(s *drawstate.State, t *template, env renderEnv) string {
 		switch o.Kind {
 		case grammar.LiteralRun:
 			b.WriteString(o.Lit)
-		case grammar.NameRead:
+		case grammar.PathRead:
 			b.WriteString(readField(s, t, env, o.arms[s.IntN(len(o.arms))]).text)
 		case grammar.BuiltinCall:
 			var operands []string

resolve.go

@@ -105,7 +105,7 @@ type columnRead struct {
 // or name, and nil where it does not.
 func columnReadOf(t *template, targets map[*nameBinding]nameTarget) *columnRead {
 	ops := t.compiled.ops
-	if t.repeat != 1 || len(ops) != 1 || ops[0].Kind != grammar.NameRead || len(ops[0].arms) != 1 {
+	if t.repeat != 1 || len(ops) != 1 || ops[0].Kind != grammar.PathRead || len(ops[0].arms) != 1 {
 		return nil
 	}
 	a := ops[0].arms[0]

struct.go

@@ -231,7 +231,7 @@ func tagValue(sf reflect.StructField, tag string) (any, error) {
 	case inline:
 		return inputValue(tag)
 	}
-	if err := grammar.CheckPathNames(tag); err != nil {
+	if err := grammar.CheckPathIdentifiers(tag); err != nil {
 		return nil, err
 	}
 	return "{/" + tag + "}", nil

table.go

@@ -167,7 +167,7 @@ func (t *table) compileRowFormat(format string) error {
 		return err
 	}
 	for _, tok := range toks {
-		if tok.Kind != grammar.NameRead {
+		if tok.Kind != grammar.PathRead {
 			continue
 		}
 		for _, name := range tok.Arms {

valueproof.go

@@ -167,7 +167,7 @@ func (p *valueProof) proveTemplate(t *template) proven.Facts {
 	o := t.compiled.ops[0]
 	body, name, args := o.Body, o.Fn, o.Args
 	switch {
-	case o.Kind == grammar.NameRead:
+	case o.Kind == grammar.PathRead:
 		var leaves []node
 		for _, a := range o.arms {
 			leaves = append(leaves, a.leaves...)