1 files changed, 0 insertions, 582 deletions
diff --git a/src/urubu/spec/grammar/parser/parser.go b/src/urubu/spec/grammar/parser/parser.go
deleted file mode 100644
index b604074..0000000
--- a/src/urubu/spec/grammar/parser/parser.go
+++ /dev/null
@@ -1,582 +0,0 @@
-package parser
-
-import (
-	"fmt"
-	"io"
-
-	verr "urubu/error"
-	spec "urubu/spec/grammar"
-)
-
-type RootNode struct {
-	Directives     []*DirectiveNode
-	Productions    []*ProductionNode
-	LexProductions []*ProductionNode
-	Fragments      []*FragmentNode
-}
-
-type ProductionNode struct {
-	Directives []*DirectiveNode
-	LHS        string
-	RHS        []*AlternativeNode
-	Pos        Position
-}
-
-func (n *ProductionNode) isLexical() bool {
-	if len(n.RHS) == 1 && len(n.RHS[0].Elements) == 1 && n.RHS[0].Elements[0].Pattern != "" {
-		return true
-	}
-	return false
-}
-
-type AlternativeNode struct {
-	Elements   []*ElementNode
-	Directives []*DirectiveNode
-	Pos        Position
-}
-
-type ElementNode struct {
-	ID        string
-	Pattern   string
-	Label     *LabelNode
-	Literally bool
-	Pos       Position
-}
-
-type LabelNode struct {
-	Name string
-	Pos  Position
-}
-
-type DirectiveNode struct {
-	Name       string
-	Parameters []*ParameterNode
-	Pos        Position
-}
-
-type ParameterNode struct {
-	ID            string
-	Pattern       string
-	String        string
-	OrderedSymbol string
-	Group         []*DirectiveNode
-	Expansion     bool
-	Pos           Position
-}
-
-type FragmentNode struct {
-	LHS string
-	RHS string
-	Pos Position
-}
-
-func raiseSyntaxError(row int, synErr *SyntaxError) {
-	panic(&verr.SpecError{
-		Cause: synErr,
-		Row:   row,
-	})
-}
-
-func raiseSyntaxErrorWithDetail(row int, synErr *SyntaxError, detail string) {
-	panic(&verr.SpecError{
-		Cause:  synErr,
-		Detail: detail,
-		Row:    row,
-	})
-}
-
-func Parse(src io.Reader) (*RootNode, error) {
-	p, err := newParser(src)
-	if err != nil {
-		return nil, err
-	}
-
-	return p.parse()
-}
-
-type parser struct {
-	lex       *lexer
-	peekedTok *token
-	lastTok   *token
-	errs      verr.SpecErrors
-
-	// A token position that the parser read at last.
-	// It is used as additional information in error messages.
-	pos Position
-}
-
-func newParser(src io.Reader) (*parser, error) {
-	lex, err := newLexer(src)
-	if err != nil {
-		return nil, err
-	}
-	return &parser{
-		lex: lex,
-	}, nil
-}
-
-func (p *parser) parse() (root *RootNode, retErr error) {
-	root = p.parseRoot()
-	if len(p.errs) > 0 {
-		return nil, p.errs
-	}
-
-	return root, nil
-}
-
-func (p *parser) parseRoot() *RootNode {
-	defer func() {
-		err := recover()
-		if err != nil {
-			specErr, ok := err.(*verr.SpecError)
-			if !ok {
-				panic(fmt.Errorf("an unexpected error occurred: %v", err))
-			}
-			p.errs = append(p.errs, specErr)
-		}
-	}()
-
-	var dirs []*DirectiveNode
-	var prods []*ProductionNode
-	var lexProds []*ProductionNode
-	var fragments []*FragmentNode
-	for {
-		dir := p.parseTopLevelDirective()
-		if dir != nil {
-			dirs = append(dirs, dir)
-			continue
-		}
-
-		fragment := p.parseFragment()
-		if fragment != nil {
-			fragments = append(fragments, fragment)
-			continue
-		}
-
-		prod := p.parseProduction()
-		if prod != nil {
-			if prod.isLexical() {
-				lexProds = append(lexProds, prod)
-			} else {
-				prods = append(prods, prod)
-			}
-			continue
-		}
-
-		if p.consume(tokenKindEOF) {
-			break
-		}
-	}
-
-	return &RootNode{
-		Directives:     dirs,
-		Productions:    prods,
-		LexProductions: lexProds,
-		Fragments:      fragments,
-	}
-}
-
-func (p *parser) parseTopLevelDirective() *DirectiveNode {
-	defer func() {
-		err := recover()
-		if err == nil {
-			return
-		}
-
-		specErr, ok := err.(*verr.SpecError)
-		if !ok {
-			panic(err)
-		}
-
-		p.errs = append(p.errs, specErr)
-		p.skipOverTo(tokenKindSemicolon)
-	}()
-
-	dir := p.parseDirective()
-	if dir == nil {
-		return nil
-	}
-
-	p.consume(tokenKindNewline)
-
-	if !p.consume(tokenKindSemicolon) {
-		raiseSyntaxError(p.pos.Row, synErrTopLevelDirNoSemicolon)
-	}
-
-	return dir
-}
-
-func (p *parser) parseFragment() *FragmentNode {
-	defer func() {
-		err := recover()
-		if err == nil {
-			return
-		}
-
-		specErr, ok := err.(*verr.SpecError)
-		if !ok {
-			panic(err)
-		}
-
-		p.errs = append(p.errs, specErr)
-		p.skipOverTo(tokenKindSemicolon)
-	}()
-
-	p.consume(tokenKindNewline)
-
-	if !p.consume(tokenKindKWFragment) {
-		return nil
-	}
-
-	p.consume(tokenKindNewline)
-
-	if !p.consume(tokenKindID) {
-		raiseSyntaxError(p.pos.Row, synErrNoProductionName)
-	}
-	lhs := p.lastTok.text
-	lhsPos := p.lastTok.pos
-
-	p.consume(tokenKindNewline)
-
-	if !p.consume(tokenKindColon) {
-		raiseSyntaxError(p.pos.Row, synErrNoColon)
-	}
-
-	var rhs string
-	switch {
-	case p.consume(tokenKindTerminalPattern):
-		rhs = p.lastTok.text
-	case p.consume(tokenKindStringLiteral):
-		rhs = spec.EscapePattern(p.lastTok.text)
-	default:
-		raiseSyntaxError(p.pos.Row, synErrFragmentNoPattern)
-	}
-
-	p.consume(tokenKindNewline)
-
-	if !p.consume(tokenKindSemicolon) {
-		raiseSyntaxError(p.pos.Row, synErrNoSemicolon)
-	}
-
-	if !p.consume(tokenKindNewline) {
-		if !p.consume(tokenKindEOF) {
-			raiseSyntaxError(p.pos.Row, synErrSemicolonNoNewline)
-		}
-	}
-
-	return &FragmentNode{
-		LHS: lhs,
-		RHS: rhs,
-		Pos: lhsPos,
-	}
-}
-
-func (p *parser) parseProduction() *ProductionNode {
-	defer func() {
-		err := recover()
-		if err == nil {
-			return
-		}
-
-		specErr, ok := err.(*verr.SpecError)
-		if !ok {
-			panic(err)
-		}
-
-		p.errs = append(p.errs, specErr)
-		p.skipOverTo(tokenKindSemicolon)
-	}()
-
-	p.consume(tokenKindNewline)
-
-	if p.consume(tokenKindEOF) {
-		return nil
-	}
-
-	if !p.consume(tokenKindID) {
-		raiseSyntaxError(p.pos.Row, synErrNoProductionName)
-	}
-	lhs := p.lastTok.text
-	lhsPos := p.lastTok.pos
-
-	var dirs []*DirectiveNode
-	for {
-		dir := p.parseDirective()
-		if dir == nil {
-			break
-		}
-		dirs = append(dirs, dir)
-	}
-
-	p.consume(tokenKindNewline)
-
-	if !p.consume(tokenKindColon) {
-		raiseSyntaxError(p.pos.Row, synErrNoColon)
-	}
-
-	alt := p.parseAlternative()
-	rhs := []*AlternativeNode{alt}
-	for {
-		p.consume(tokenKindNewline)
-
-		if !p.consume(tokenKindOr) {
-			break
-		}
-		alt := p.parseAlternative()
-		rhs = append(rhs, alt)
-	}
-
-	p.consume(tokenKindNewline)
-
-	if !p.consume(tokenKindSemicolon) {
-		raiseSyntaxError(p.pos.Row, synErrNoSemicolon)
-	}
-
-	if !p.consume(tokenKindNewline) {
-		if !p.consume(tokenKindEOF) {
-			raiseSyntaxError(p.pos.Row, synErrSemicolonNoNewline)
-		}
-	}
-
-	prod := &ProductionNode{
-		Directives: dirs,
-		LHS:        lhs,
-		RHS:        rhs,
-		Pos:        lhsPos,
-	}
-
-	// Vartan's driver must provide a user with the names of expected tokens when a syntax error occurs.
-	// However, if a pattern appears directly in an alternative, Vartan's compiler cannot assign an appropriate
-	// name to the pattern. Therefore, this code prohibits alternatives from containing patterns.
-	if !prod.isLexical() {
-		for _, alt := range prod.RHS {
-			for _, elem := range alt.Elements {
-				if elem.Pattern != "" {
-					raiseSyntaxError(elem.Pos.Row, synErrPatternInAlt)
-				}
-			}
-		}
-	}
-
-	return prod
-}
-
-func (p *parser) parseAlternative() *AlternativeNode {
-	elems := []*ElementNode{}
-	for {
-		elem := p.parseElement()
-		if elem == nil {
-			break
-		}
-		elems = append(elems, elem)
-	}
-
-	// When a length of an alternative is zero, we cannot set a position.
-	var firstElemPos Position
-	if len(elems) > 0 {
-		firstElemPos = elems[0].Pos
-	}
-
-	var dirs []*DirectiveNode
-	for {
-		dir := p.parseDirective()
-		if dir == nil {
-			break
-		}
-		dirs = append(dirs, dir)
-	}
-
-	return &AlternativeNode{
-		Elements:   elems,
-		Directives: dirs,
-		Pos:        firstElemPos,
-	}
-}
-
-func (p *parser) parseElement() *ElementNode {
-	var elem *ElementNode
-	switch {
-	case p.consume(tokenKindID):
-		elem = &ElementNode{
-			ID:  p.lastTok.text,
-			Pos: p.lastTok.pos,
-		}
-	case p.consume(tokenKindTerminalPattern):
-		elem = &ElementNode{
-			Pattern: p.lastTok.text,
-			Pos:     p.lastTok.pos,
-		}
-	case p.consume(tokenKindStringLiteral):
-		elem = &ElementNode{
-			Pattern:   p.lastTok.text,
-			Literally: true,
-			Pos:       p.lastTok.pos,
-		}
-	default:
-		if p.consume(tokenKindLabelMarker) {
-			raiseSyntaxError(p.pos.Row, synErrLabelWithNoSymbol)
-		}
-		return nil
-	}
-	if p.consume(tokenKindLabelMarker) {
-		if !p.consume(tokenKindID) {
-			raiseSyntaxError(p.pos.Row, synErrNoLabel)
-		}
-		elem.Label = &LabelNode{
-			Name: p.lastTok.text,
-			Pos:  p.lastTok.pos,
-		}
-	}
-	return elem
-}
-
-func (p *parser) parseDirective() *DirectiveNode {
-	p.consume(tokenKindNewline)
-
-	if !p.consume(tokenKindDirectiveMarker) {
-		return nil
-	}
-	dirPos := p.lastTok.pos
-
-	if !p.consume(tokenKindID) {
-		raiseSyntaxError(p.pos.Row, synErrNoDirectiveName)
-	}
-	name := p.lastTok.text
-
-	var params []*ParameterNode
-	for {
-		param := p.parseParameter()
-		if param == nil {
-			break
-		}
-		params = append(params, param)
-	}
-
-	return &DirectiveNode{
-		Name:       name,
-		Parameters: params,
-		Pos:        dirPos,
-	}
-}
-
-func (p *parser) parseParameter() *ParameterNode {
-	var param *ParameterNode
-	switch {
-	case p.consume(tokenKindID):
-		param = &ParameterNode{
-			ID:  p.lastTok.text,
-			Pos: p.lastTok.pos,
-		}
-	case p.consume(tokenKindTerminalPattern):
-		param = &ParameterNode{
-			Pattern: p.lastTok.text,
-			Pos:     p.lastTok.pos,
-		}
-	case p.consume(tokenKindStringLiteral):
-		param = &ParameterNode{
-			String: p.lastTok.text,
-			Pos:    p.lastTok.pos,
-		}
-	case p.consume(tokenKindOrderedSymbolMarker):
-		if !p.consume(tokenKindID) {
-			raiseSyntaxError(p.pos.Row, synErrNoOrderedSymbolName)
-		}
-		param = &ParameterNode{
-			OrderedSymbol: p.lastTok.text,
-			Pos:           p.lastTok.pos,
-		}
-	case p.consume(tokenKindLParen):
-		pos := p.lastTok.pos
-		var g []*DirectiveNode
-		for {
-			dir := p.parseDirective()
-			if dir == nil {
-				break
-			}
-			g = append(g, dir)
-		}
-		if !p.consume(tokenKindRParen) {
-			raiseSyntaxError(p.pos.Row, synErrUnclosedDirGroup)
-		}
-		if len(g) == 0 {
-			// Set an empty slice representing an empty directive group to distinguish between the following two cases.
-			//
-			// - #prec (); // vartan allows this case.
-			// - #prec;    // This case will raise an error.
-			g = []*DirectiveNode{}
-		}
-		param = &ParameterNode{
-			Group: g,
-			Pos:   pos,
-		}
-	}
-	if p.consume(tokenKindExpantion) {
-		switch {
-		case param == nil:
-			raiseSyntaxError(p.pos.Row, synErrStrayExpOp)
-		case param.ID == "":
-			raiseSyntaxError(p.pos.Row, synErrInvalidExpOperand)
-		}
-		param.Expansion = true
-	}
-	return param
-}
-
-func (p *parser) consume(expected tokenKind) bool {
-	var tok *token
-	var err error
-	if p.peekedTok != nil {
-		tok = p.peekedTok
-		p.peekedTok = nil
-	} else {
-		tok, err = p.lex.next()
-		if err != nil {
-			panic(err)
-		}
-	}
-	p.pos = tok.pos
-	if tok.kind == tokenKindInvalid {
-		raiseSyntaxErrorWithDetail(p.pos.Row, synErrInvalidToken, tok.text)
-	}
-	if tok.kind == expected {
-		p.lastTok = tok
-		return true
-	}
-	p.peekedTok = tok
-
-	return false
-}
-
-func (p *parser) skip() {
-	var tok *token
-	var err error
-	for {
-		if p.peekedTok != nil {
-			tok = p.peekedTok
-			p.peekedTok = nil
-		} else {
-			tok, err = p.lex.next()
-			if err != nil {
-				p.errs = append(p.errs, &verr.SpecError{
-					Cause: err,
-					Row:   p.pos.Row,
-				})
-				continue
-			}
-		}
-
-		break
-	}
-
-	p.lastTok = tok
-	p.pos = tok.pos
-}
-
-func (p *parser) skipOverTo(kind tokenKind) {
-	for {
-		if p.consume(kind) || p.consume(tokenKindEOF) {
-			return
-		}
-		p.skip()
-	}
-}