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-rw-r--r--spec/test/tree_lexer.go549
1 files changed, 549 insertions, 0 deletions
diff --git a/spec/test/tree_lexer.go b/spec/test/tree_lexer.go
new file mode 100644
index 0000000..931626f
--- /dev/null
+++ b/spec/test/tree_lexer.go
@@ -0,0 +1,549 @@
+// Code generated by maleeni-go. DO NOT EDIT.
+package test
+
+import (
+ "fmt"
+ "io"
+ "io/ioutil"
+)
+
+type ModeID int
+
+func (id ModeID) Int() int {
+ return int(id)
+}
+
+type StateID int
+
+func (id StateID) Int() int {
+ return int(id)
+}
+
+type KindID int
+
+func (id KindID) Int() int {
+ return int(id)
+}
+
+type ModeKindID int
+
+func (id ModeKindID) Int() int {
+ return int(id)
+}
+
+type LexSpec interface {
+ InitialMode() ModeID
+ Pop(mode ModeID, modeKind ModeKindID) bool
+ Push(mode ModeID, modeKind ModeKindID) (ModeID, bool)
+ ModeName(mode ModeID) string
+ InitialState(mode ModeID) StateID
+ NextState(mode ModeID, state StateID, v int) (StateID, bool)
+ Accept(mode ModeID, state StateID) (ModeKindID, bool)
+ KindIDAndName(mode ModeID, modeKind ModeKindID) (KindID, string)
+}
+
+// Token representes a token.
+type Token struct {
+ // ModeID is an ID of a lex mode.
+ ModeID ModeID
+
+ // KindID is an ID of a kind. This is unique among all modes.
+ KindID KindID
+
+ // ModeKindID is an ID of a lexical kind. This is unique only within a mode.
+ // Note that you need to use KindID field if you want to identify a kind across all modes.
+ ModeKindID ModeKindID
+
+ // Row is a row number where a lexeme appears.
+ Row int
+
+ // Col is a column number where a lexeme appears.
+ // Note that Col is counted in code points, not bytes.
+ Col int
+
+ // Lexeme is a byte sequence matched a pattern of a lexical specification.
+ Lexeme []byte
+
+ // When this field is true, it means the token is the EOF token.
+ EOF bool
+
+ // When this field is true, it means the token is an error token.
+ Invalid bool
+}
+
+type LexerOption func(l *Lexer) error
+
+// DisableModeTransition disables the active mode transition. Thus, even if the lexical specification has the push and pop
+// operations, the lexer doesn't perform these operations. When the lexical specification has multiple modes, and this option is
+// enabled, you need to call the Lexer.Push and Lexer.Pop methods to perform the mode transition. You can use the Lexer.Mode method
+// to know the current lex mode.
+func DisableModeTransition() LexerOption {
+ return func(l *Lexer) error {
+ l.passiveModeTran = true
+ return nil
+ }
+}
+
+type Lexer struct {
+ spec LexSpec
+ src []byte
+ srcPtr int
+ row int
+ col int
+ prevRow int
+ prevCol int
+ tokBuf []*Token
+ modeStack []ModeID
+ passiveModeTran bool
+}
+
+// NewLexer returns a new lexer.
+func NewLexer(spec LexSpec, src io.Reader, opts ...LexerOption) (*Lexer, error) {
+ b, err := ioutil.ReadAll(src)
+ if err != nil {
+ return nil, err
+ }
+ l := &Lexer{
+ spec: spec,
+ src: b,
+ srcPtr: 0,
+ row: 0,
+ col: 0,
+ modeStack: []ModeID{
+ spec.InitialMode(),
+ },
+ passiveModeTran: false,
+ }
+ for _, opt := range opts {
+ err := opt(l)
+ if err != nil {
+ return nil, err
+ }
+ }
+
+ return l, nil
+}
+
+// Next returns a next token.
+func (l *Lexer) Next() (*Token, error) {
+ if len(l.tokBuf) > 0 {
+ tok := l.tokBuf[0]
+ l.tokBuf = l.tokBuf[1:]
+ return tok, nil
+ }
+
+ tok, err := l.nextAndTransition()
+ if err != nil {
+ return nil, err
+ }
+ if !tok.Invalid {
+ return tok, nil
+ }
+ errTok := tok
+ for {
+ tok, err = l.nextAndTransition()
+ if err != nil {
+ return nil, err
+ }
+ if !tok.Invalid {
+ break
+ }
+ errTok.Lexeme = append(errTok.Lexeme, tok.Lexeme...)
+ }
+ l.tokBuf = append(l.tokBuf, tok)
+
+ return errTok, nil
+}
+
+func (l *Lexer) nextAndTransition() (*Token, error) {
+ tok, err := l.next()
+ if err != nil {
+ return nil, err
+ }
+ if tok.EOF || tok.Invalid {
+ return tok, nil
+ }
+ if l.passiveModeTran {
+ return tok, nil
+ }
+ mode := l.Mode()
+ if l.spec.Pop(mode, tok.ModeKindID) {
+ err := l.PopMode()
+ if err != nil {
+ return nil, err
+ }
+ }
+ if mode, ok := l.spec.Push(mode, tok.ModeKindID); ok {
+ l.PushMode(mode)
+ }
+ // The checking length of the mode stack must be at after pop and push operations because those operations can be performed
+ // at the same time. When the mode stack has just one element and popped it, the mode stack will be temporarily emptied.
+ // However, since a push operation may be performed immediately after it, the lexer allows the stack to be temporarily empty.
+ if len(l.modeStack) == 0 {
+ return nil, fmt.Errorf("a mode stack must have at least one element")
+ }
+ return tok, nil
+}
+
+func (l *Lexer) next() (*Token, error) {
+ mode := l.Mode()
+ state := l.spec.InitialState(mode)
+ buf := []byte{}
+ unfixedBufLen := 0
+ row := l.row
+ col := l.col
+ var tok *Token
+ for {
+ v, eof := l.read()
+ if eof {
+ if tok != nil {
+ l.unread(unfixedBufLen)
+ return tok, nil
+ }
+ // When `buf` has unaccepted data and reads the EOF, the lexer treats the buffered data as an invalid token.
+ if len(buf) > 0 {
+ return &Token{
+ ModeID: mode,
+ ModeKindID: 0,
+ Lexeme: buf,
+ Row: row,
+ Col: col,
+ Invalid: true,
+ }, nil
+ }
+ return &Token{
+ ModeID: mode,
+ ModeKindID: 0,
+ Row: 0,
+ Col: 0,
+ EOF: true,
+ }, nil
+ }
+ buf = append(buf, v)
+ unfixedBufLen++
+ nextState, ok := l.spec.NextState(mode, state, int(v))
+ if !ok {
+ if tok != nil {
+ l.unread(unfixedBufLen)
+ return tok, nil
+ }
+ return &Token{
+ ModeID: mode,
+ ModeKindID: 0,
+ Lexeme: buf,
+ Row: row,
+ Col: col,
+ Invalid: true,
+ }, nil
+ }
+ state = nextState
+ if modeKindID, ok := l.spec.Accept(mode, state); ok {
+ kindID, _ := l.spec.KindIDAndName(mode, modeKindID)
+ tok = &Token{
+ ModeID: mode,
+ KindID: kindID,
+ ModeKindID: modeKindID,
+ Lexeme: buf,
+ Row: row,
+ Col: col,
+ }
+ unfixedBufLen = 0
+ }
+ }
+}
+
+// Mode returns the current lex mode.
+func (l *Lexer) Mode() ModeID {
+ return l.modeStack[len(l.modeStack)-1]
+}
+
+// PushMode adds a lex mode onto the mode stack.
+func (l *Lexer) PushMode(mode ModeID) {
+ l.modeStack = append(l.modeStack, mode)
+}
+
+// PopMode removes a lex mode from the top of the mode stack.
+func (l *Lexer) PopMode() error {
+ sLen := len(l.modeStack)
+ if sLen == 0 {
+ return fmt.Errorf("cannot pop a lex mode from a lex mode stack any more")
+ }
+ l.modeStack = l.modeStack[:sLen-1]
+ return nil
+}
+
+func (l *Lexer) read() (byte, bool) {
+ if l.srcPtr >= len(l.src) {
+ return 0, true
+ }
+
+ b := l.src[l.srcPtr]
+ l.srcPtr++
+
+ l.prevRow = l.row
+ l.prevCol = l.col
+
+ // Count the token positions.
+ // The driver treats LF as the end of lines and counts columns in code points, not bytes.
+ // To count in code points, we refer to the First Byte column in the Table 3-6.
+ //
+ // Reference:
+ // - [Table 3-6] https://www.unicode.org/versions/Unicode13.0.0/ch03.pdf > Table 3-6. UTF-8 Bit Distribution
+ if b < 128 {
+ // 0x0A is LF.
+ if b == 0x0A {
+ l.row++
+ l.col = 0
+ } else {
+ l.col++
+ }
+ } else if b>>5 == 6 || b>>4 == 14 || b>>3 == 30 {
+ l.col++
+ }
+
+ return b, false
+}
+
+// We must not call this function consecutively to record the token position correctly.
+func (l *Lexer) unread(n int) {
+ l.srcPtr -= n
+
+ l.row = l.prevRow
+ l.col = l.prevCol
+}
+
+const (
+ ModeIDNil ModeID = 0
+ ModeIDDefault ModeID = 1
+)
+
+const (
+ ModeNameNil = ""
+ ModeNameDefault = "default"
+)
+
+// ModeIDToName converts a mode ID to a name.
+func ModeIDToName(id ModeID) string {
+ switch id {
+ case ModeIDNil:
+ return ModeNameNil
+ case ModeIDDefault:
+ return ModeNameDefault
+ }
+ return ""
+}
+
+const (
+ KindIDNil KindID = 0
+ KindIDWs KindID = 1
+ KindIDLParen KindID = 2
+ KindIDRParen KindID = 3
+ KindIDIdentifier KindID = 4
+)
+
+const (
+ KindNameNil = ""
+ KindNameWs = "ws"
+ KindNameLParen = "l_paren"
+ KindNameRParen = "r_paren"
+ KindNameIdentifier = "identifier"
+)
+
+// KindIDToName converts a kind ID to a name.
+func KindIDToName(id KindID) string {
+ switch id {
+ case KindIDNil:
+ return KindNameNil
+ case KindIDWs:
+ return KindNameWs
+ case KindIDLParen:
+ return KindNameLParen
+ case KindIDRParen:
+ return KindNameRParen
+ case KindIDIdentifier:
+ return KindNameIdentifier
+ }
+ return ""
+}
+
+type lexSpec struct {
+ pop [][]bool
+ push [][]ModeID
+ modeNames []string
+ initialStates []StateID
+ acceptances [][]ModeKindID
+ kindIDs [][]KindID
+ kindNames []string
+ initialModeID ModeID
+ modeIDNil ModeID
+ modeKindIDNil ModeKindID
+ stateIDNil StateID
+
+ rowNums [][]int
+ rowDisplacements [][]int
+ bounds [][]int
+ entries [][]StateID
+ originalColCounts []int
+}
+
+func NewLexSpec() *lexSpec {
+ return &lexSpec{
+ pop: [][]bool{
+ nil,
+ {
+ false, false, false, false, false,
+ },
+ },
+ push: [][]ModeID{
+ nil,
+ {
+ 0, 0, 0, 0, 0,
+ },
+ },
+ modeNames: []string{
+ ModeNameNil,
+ ModeNameDefault,
+ },
+ initialStates: []StateID{
+ 0,
+ 1,
+ },
+ acceptances: [][]ModeKindID{
+ nil,
+ {
+ 0, 0, 1, 4, 2, 3,
+ },
+ },
+ kindIDs: [][]KindID{
+ nil,
+ {
+ KindIDNil,
+ KindIDWs,
+ KindIDLParen,
+ KindIDRParen,
+ KindIDIdentifier,
+ },
+ },
+ kindNames: []string{
+ KindNameNil,
+ KindNameWs,
+ KindNameLParen,
+ KindNameRParen,
+ KindNameIdentifier,
+ },
+ initialModeID: ModeIDDefault,
+ modeIDNil: ModeIDNil,
+ modeKindIDNil: 0,
+ stateIDNil: 0,
+
+ rowNums: [][]int{
+ nil,
+ {
+ 0, 1, 2, 3, 0, 0,
+ },
+ },
+ rowDisplacements: [][]int{
+ nil,
+ {
+ 0, 0, 189, 75,
+ },
+ },
+ bounds: [][]int{
+ nil,
+ {
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, 1, 1, -1, -1, 1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 1, -1, -1, -1, -1, -1, -1, -1,
+ 1, 1, -1, -1, -1, -1, -1, -1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1,
+ -1, -1, -1, -1, -1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, 1, -1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, -1, -1, -1, -1, -1, -1, -1,
+ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+ 3, 3, 3, 3, 3, 3, -1, -1, -1, -1, 3, -1, 3, 3, 3, 3, 3, 3, 3, 3,
+ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2,
+ -1, -1, 2, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, 2, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1,
+ },
+ },
+ entries: [][]StateID{
+ nil,
+ {
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 0, 0, 2, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0,
+ 4, 5, 0, 0, 0, 0, 0, 0, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 0, 0,
+ 0, 0, 0, 0, 0, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 0, 0, 0, 0, 3, 0, 3, 3, 3,
+ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 0, 0, 0, 0, 0, 0, 0,
+ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+ 3, 3, 3, 3, 3, 3, 0, 0, 0, 0, 3, 0, 3, 3, 3, 3, 3, 3, 3, 3,
+ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2,
+ 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0,
+ },
+ },
+ originalColCounts: nil,
+ }
+}
+
+func (s *lexSpec) InitialMode() ModeID {
+ return s.initialModeID
+}
+
+func (s *lexSpec) Pop(mode ModeID, modeKind ModeKindID) bool {
+ return s.pop[mode][modeKind]
+}
+
+func (s *lexSpec) Push(mode ModeID, modeKind ModeKindID) (ModeID, bool) {
+ id := s.push[mode][modeKind]
+ return id, id != s.modeIDNil
+}
+
+func (s *lexSpec) ModeName(mode ModeID) string {
+ return s.modeNames[mode]
+}
+
+func (s *lexSpec) InitialState(mode ModeID) StateID {
+ return s.initialStates[mode]
+}
+
+func (s *lexSpec) NextState(mode ModeID, state StateID, v int) (StateID, bool) {
+ rowNum := s.rowNums[mode][state]
+ d := s.rowDisplacements[mode][rowNum]
+ if s.bounds[mode][d+v] != rowNum {
+ return s.stateIDNil, false
+ }
+ return s.entries[mode][d+v], true
+}
+
+func (s *lexSpec) Accept(mode ModeID, state StateID) (ModeKindID, bool) {
+ id := s.acceptances[mode][state]
+ return id, id != s.modeKindIDNil
+}
+
+func (s *lexSpec) KindIDAndName(mode ModeID, modeKind ModeKindID) (KindID, string) {
+ id := s.kindIDs[mode][modeKind]
+ return id, s.kindNames[id]
+}
generated by cgit v1.2.3 (git 2.49.0) at 2025-07-06 10:08:51 +0000