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-rw-r--r--driver/parser/conflict_test.go524
-rw-r--r--driver/parser/lac_test.go120
-rw-r--r--driver/parser/parser.go416
-rw-r--r--driver/parser/parser_test.go833
-rw-r--r--driver/parser/semantic_action.go371
-rw-r--r--driver/parser/semantic_action_test.go227
-rw-r--r--driver/parser/spec.go73
-rw-r--r--driver/parser/syntax_error_test.go306
-rw-r--r--driver/parser/template.go535
-rw-r--r--driver/parser/token_stream.go65
10 files changed, 0 insertions, 3470 deletions
diff --git a/driver/parser/conflict_test.go b/driver/parser/conflict_test.go
deleted file mode 100644
index 1a75483..0000000
--- a/driver/parser/conflict_test.go
+++ /dev/null
@@ -1,524 +0,0 @@
-package parser
-
-import (
- "strings"
- "testing"
-
- "grammar"
- "spec/grammar/parser"
-)
-
-func TestParserWithConflicts(t *testing.T) {
- tests := []struct {
- caption string
- specSrc string
- src string
- cst *Node
- }{
- {
- caption: "when a shift/reduce conflict occurred, we prioritize the shift action",
- specSrc: `
-#name test;
-
-expr
- : expr assign expr
- | id
- ;
-
-id: "[A-Za-z0-9_]+";
-assign: '=';
-`,
- src: `foo=bar=baz`,
- cst: nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "foo"),
- ),
- termNode("assign", "="),
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "bar"),
- ),
- termNode("assign", "="),
- nonTermNode("expr",
- termNode("id", "baz"),
- ),
- ),
- ),
- },
- {
- caption: "when a reduce/reduce conflict occurred, we prioritize the production defined earlier in the grammar",
- specSrc: `
-#name test;
-
-s
- : a
- | b
- ;
-a
- : id
- ;
-b
- : id
- ;
-
-id: "[A-Za-z0-9_]+";
-`,
- src: `foo`,
- cst: nonTermNode("s",
- nonTermNode("a",
- termNode("id", "foo"),
- ),
- ),
- },
- {
- caption: "left associativities defined earlier in the grammar have higher precedence",
- specSrc: `
-#name test;
-
-#prec (
- #left mul
- #left add
-);
-
-expr
- : expr add expr
- | expr mul expr
- | id
- ;
-
-id: "[A-Za-z0-9_]+";
-add: '+';
-mul: '*';
-`,
- src: `a+b*c*d+e`,
- cst: nonTermNode("expr",
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "a"),
- ),
- termNode("add", "+"),
- nonTermNode("expr",
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "b"),
- ),
- termNode("mul", "*"),
- nonTermNode("expr",
- termNode("id", "c"),
- ),
- ),
- termNode("mul", "*"),
- nonTermNode("expr",
- termNode("id", "d"),
- ),
- ),
- ),
- termNode("add", "+"),
- nonTermNode("expr",
- termNode("id", "e"),
- ),
- ),
- },
- {
- caption: "left associativities defined in the same line have the same precedence",
- specSrc: `
-#name test;
-
-#prec (
- #left add sub
-);
-
-expr
- : expr add expr
- | expr sub expr
- | id
- ;
-
-id: "[A-Za-z0-9_]+";
-add: '+';
-sub: '-';
-`,
- src: `a-b+c+d-e`,
- cst: nonTermNode("expr",
- nonTermNode("expr",
- nonTermNode("expr",
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "a"),
- ),
- termNode("sub", "-"),
- nonTermNode("expr",
- termNode("id", "b"),
- ),
- ),
- termNode("add", "+"),
- nonTermNode("expr",
- termNode("id", "c"),
- ),
- ),
- termNode("add", "+"),
- nonTermNode("expr",
- termNode("id", "d"),
- ),
- ),
- termNode("sub", "-"),
- nonTermNode("expr",
- termNode("id", "e"),
- ),
- ),
- },
- {
- caption: "right associativities defined earlier in the grammar have higher precedence",
- specSrc: `
-#name test;
-
-#prec (
- #right r1
- #right r2
-);
-
-expr
- : expr r2 expr
- | expr r1 expr
- | id
- ;
-
-whitespaces #skip
- : "[\u{0009}\u{0020}]+";
-r1
- : 'r1';
-r2
- : 'r2';
-id
- : "[A-Za-z0-9_]+";
-`,
- src: `a r2 b r1 c r1 d r2 e`,
- cst: nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "a"),
- ),
- termNode("r2", "r2"),
- nonTermNode("expr",
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "b"),
- ),
- termNode("r1", "r1"),
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "c"),
- ),
- termNode("r1", "r1"),
- nonTermNode("expr",
- termNode("id", "d"),
- ),
- ),
- ),
- termNode("r2", "r2"),
- nonTermNode("expr",
- termNode("id", "e"),
- ),
- ),
- ),
- },
- {
- caption: "right associativities defined in the same line have the same precedence",
- specSrc: `
-#name test;
-
-#prec (
- #right r1 r2
-);
-
-expr
- : expr r2 expr
- | expr r1 expr
- | id
- ;
-
-whitespaces #skip
- : "[\u{0009}\u{0020}]+";
-r1
- : 'r1';
-r2
- : 'r2';
-id
- : "[A-Za-z0-9_]+";
-`,
- src: `a r2 b r1 c r1 d r2 e`,
- cst: nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "a"),
- ),
- termNode("r2", "r2"),
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "b"),
- ),
- termNode("r1", "r1"),
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "c"),
- ),
- termNode("r1", "r1"),
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "d"),
- ),
- termNode("r2", "r2"),
- nonTermNode("expr",
- termNode("id", "e"),
- ),
- ),
- ),
- ),
- ),
- },
- {
- caption: "terminal symbols with an #assign directive defined earlier in the grammar have higher precedence",
- specSrc: `
-#name test;
-
-#prec (
- #assign a1
- #assign a2
-);
-
-expr
- : expr a2 expr
- | expr a1 expr
- | id
- ;
-
-whitespaces #skip
- : "[\u{0009}\u{0020}]+";
-a1
- : 'a1';
-a2
- : 'a2';
-id
- : "[A-Za-z0-9_]+";
-`,
- src: `a a2 b a1 c a1 d a2 e`,
- cst: nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "a"),
- ),
- termNode("a2", "a2"),
- nonTermNode("expr",
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "b"),
- ),
- termNode("a1", "a1"),
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "c"),
- ),
- termNode("a1", "a1"),
- nonTermNode("expr",
- termNode("id", "d"),
- ),
- ),
- ),
- termNode("a2", "a2"),
- nonTermNode("expr",
- termNode("id", "e"),
- ),
- ),
- ),
- },
- {
- caption: "terminal symbols with an #assign directive defined in the same line have the same precedence",
- specSrc: `
-#name test;
-
-#prec (
- #assign a1 a2
-);
-
-expr
- : expr a2 expr
- | expr a1 expr
- | id
- ;
-
-whitespaces #skip
- : "[\u{0009}\u{0020}]+";
-a1
- : 'a1';
-a2
- : 'a2';
-id
- : "[A-Za-z0-9_]+";
-`,
- src: `a a2 b a1 c a1 d a2 e`,
- cst: nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "a"),
- ),
- termNode("a2", "a2"),
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "b"),
- ),
- termNode("a1", "a1"),
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "c"),
- ),
- termNode("a1", "a1"),
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "d"),
- ),
- termNode("a2", "a2"),
- nonTermNode("expr",
- termNode("id", "e"),
- ),
- ),
- ),
- ),
- ),
- },
- {
- caption: "#left, #right, and #assign can be mixed",
- specSrc: `
-#name test;
-
-#prec (
- #left mul div
- #left add sub
- #assign else
- #assign then
- #right assign
-);
-
-expr
- : expr add expr
- | expr sub expr
- | expr mul expr
- | expr div expr
- | expr assign expr
- | if expr then expr
- | if expr then expr else expr
- | id
- ;
-
-ws #skip: "[\u{0009}\u{0020}]+";
-if: 'if';
-then: 'then';
-else: 'else';
-id: "[A-Za-z0-9_]+";
-add: '+';
-sub: '-';
-mul: '*';
-div: '/';
-assign: '=';
-`,
- src: `x = y = a + b * c - d / e + if f then if g then h else i`,
- cst: nonTermNode(
- "expr",
- nonTermNode("expr",
- termNode("id", "x"),
- ),
- termNode("assign", "="),
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "y"),
- ),
- termNode("assign", "="),
- nonTermNode("expr",
- nonTermNode("expr",
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "a"),
- ),
- termNode("add", "+"),
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "b"),
- ),
- termNode("mul", "*"),
- nonTermNode("expr",
- termNode("id", "c"),
- ),
- ),
- ),
- termNode("sub", "-"),
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("id", "d"),
- ),
- termNode("div", "/"),
- nonTermNode("expr",
- termNode("id", "e"),
- ),
- ),
- ),
- termNode("add", "+"),
- nonTermNode("expr",
- termNode("if", "if"),
- nonTermNode("expr",
- termNode("id", "f"),
- ),
- termNode("then", "then"),
- nonTermNode("expr",
- termNode("if", "if"),
- nonTermNode("expr",
- termNode("id", "g"),
- ),
- termNode("then", "then"),
- nonTermNode("expr",
- termNode("id", "h"),
- ),
- termNode("else", "else"),
- nonTermNode("expr",
- termNode("id", "i"),
- ),
- ),
- ),
- ),
- ),
- ),
- },
- }
-
- for _, tt := range tests {
- t.Run(tt.caption, func(t *testing.T) {
- ast, err := parser.Parse(strings.NewReader(tt.specSrc))
- if err != nil {
- t.Fatal(err)
- }
-
- b := grammar.GrammarBuilder{
- AST: ast,
- }
- cg, _, err := b.Build()
- if err != nil {
- t.Fatal(err)
- }
-
- toks, err := NewTokenStream(cg, strings.NewReader(tt.src))
- if err != nil {
- t.Fatal(err)
- }
-
- gram := NewGrammar(cg)
- tb := NewDefaultSyntaxTreeBuilder()
- p, err := NewParser(toks, gram, SemanticAction(NewCSTActionSet(gram, tb)))
- if err != nil {
- t.Fatal(err)
- }
-
- err = p.Parse()
- if err != nil {
- t.Fatal(err)
- }
-
- if tt.cst != nil {
- testTree(t, tb.Tree(), tt.cst)
- }
- })
- }
-}
diff --git a/driver/parser/lac_test.go b/driver/parser/lac_test.go
deleted file mode 100644
index ed9a0b8..0000000
--- a/driver/parser/lac_test.go
+++ /dev/null
@@ -1,120 +0,0 @@
-package parser
-
-import (
- "strings"
- "testing"
-
- "grammar"
- "spec/grammar/parser"
-)
-
-func TestParserWithLAC(t *testing.T) {
- specSrc := `
-#name test;
-
-s
- : t t
- ;
-t
- : c t
- | d
- ;
-
-c: 'c';
-d: 'd';
-`
-
- src := `ccd`
-
- actLogWithLAC := []string{
- "shift/c",
- "shift/c",
- "shift/d",
- "miss",
- }
-
- actLogWithoutLAC := []string{
- "shift/c",
- "shift/c",
- "shift/d",
- "reduce/t",
- "reduce/t",
- "reduce/t",
- "miss",
- }
-
- ast, err := parser.Parse(strings.NewReader(specSrc))
- if err != nil {
- t.Fatal(err)
- }
-
- b := grammar.GrammarBuilder{
- AST: ast,
- }
- gram, _, err := b.Build()
- if err != nil {
- t.Fatal(err)
- }
-
- t.Run("LAC is enabled", func(t *testing.T) {
- semAct := &testSemAct{
- gram: gram,
- }
-
- toks, err := NewTokenStream(gram, strings.NewReader(src))
- if err != nil {
- t.Fatal(err)
- }
-
- p, err := NewParser(toks, NewGrammar(gram), SemanticAction(semAct))
- if err != nil {
- t.Fatal(err)
- }
-
- err = p.Parse()
- if err != nil {
- t.Fatal(err)
- }
-
- if len(semAct.actLog) != len(actLogWithLAC) {
- t.Fatalf("unexpected action log; want: %+v, got: %+v", actLogWithLAC, semAct.actLog)
- }
-
- for i, e := range actLogWithLAC {
- if semAct.actLog[i] != e {
- t.Fatalf("unexpected action log; want: %+v, got: %+v", actLogWithLAC, semAct.actLog)
- }
- }
- })
-
- t.Run("LAC is disabled", func(t *testing.T) {
- semAct := &testSemAct{
- gram: gram,
- }
-
- toks, err := NewTokenStream(gram, strings.NewReader(src))
- if err != nil {
- t.Fatal(err)
- }
-
- p, err := NewParser(toks, NewGrammar(gram), SemanticAction(semAct), DisableLAC())
- if err != nil {
- t.Fatal(err)
- }
-
- err = p.Parse()
- if err != nil {
- t.Fatal(err)
- }
-
- if len(semAct.actLog) != len(actLogWithoutLAC) {
- t.Fatalf("unexpected action log; want: %+v, got: %+v", actLogWithoutLAC, semAct.actLog)
- }
-
- for i, e := range actLogWithoutLAC {
- if semAct.actLog[i] != e {
- t.Fatalf("unexpected action log; want: %+v, got: %+v", actLogWithoutLAC, semAct.actLog)
- }
- }
- })
-}
diff --git a/driver/parser/parser.go b/driver/parser/parser.go
deleted file mode 100644
index 2eaa678..0000000
--- a/driver/parser/parser.go
+++ /dev/null
@@ -1,416 +0,0 @@
-package parser
-
-import (
- "fmt"
-)
-
-type Grammar interface {
- // InitialState returns the initial state of a parser.
- InitialState() int
-
- // StartProduction returns the start production of grammar.
- StartProduction() int
-
- // Action returns an ACTION entry corresponding to a (state, terminal symbol) pair.
- Action(state int, terminal int) int
-
- // GoTo returns a GOTO entry corresponding to a (state, non-terminal symbol) pair.
- GoTo(state int, lhs int) int
-
- // ErrorTrapperState returns true when a state can shift the error symbol.
- ErrorTrapperState(state int) bool
-
- // LHS returns a LHS symbol of a production.
- LHS(prod int) int
-
- // AlternativeSymbolCount returns a symbol count of p production.
- AlternativeSymbolCount(prod int) int
-
- // RecoverProduction returns true when a production has the recover directive.
- RecoverProduction(prod int) bool
-
- // NonTerminal retuns a string representaion of a non-terminal symbol.
- NonTerminal(nonTerminal int) string
-
- // TerminalCount returns a terminal symbol count of grammar.
- TerminalCount() int
-
- // SkipTerminal returns true when a terminal symbol must be skipped on syntax analysis.
- SkipTerminal(terminal int) bool
-
- // EOF returns the EOF symbol.
- EOF() int
-
- // Error returns the error symbol.
- Error() int
-
- // Terminal retuns a string representaion of a terminal symbol.
- Terminal(terminal int) string
-
- // ASTAction returns an AST action entries.
- ASTAction(prod int) []int
-}
-
-type VToken interface {
- // TerminalID returns a terminal ID.
- TerminalID() int
-
- // Lexeme returns a lexeme.
- Lexeme() []byte
-
- // EOF returns true when a token represents EOF.
- EOF() bool
-
- // Invalid returns true when a token is invalid.
- Invalid() bool
-
- // BytePosition returns (position, length) pair.
- // `position` is a byte position where a token appears and `length` is a length in bytes.
- BytePosition() (int, int)
-
- // Position returns (row, column) pair.
- Position() (int, int)
-}
-
-type TokenStream interface {
- Next() (VToken, error)
-}
-
-type SyntaxError struct {
- Row int
- Col int
- Message string
- Token VToken
- ExpectedTerminals []string
-}
-
-type ParserOption func(p *Parser) error
-
-// DisableLAC disables LAC (lookahead correction). LAC is enabled by default.
-func DisableLAC() ParserOption {
- return func(p *Parser) error {
- p.disableLAC = true
- return nil
- }
-}
-
-func SemanticAction(semAct SemanticActionSet) ParserOption {
- return func(p *Parser) error {
- p.semAct = semAct
- return nil
- }
-}
-
-type Parser struct {
- toks TokenStream
- gram Grammar
- stateStack *stateStack
- semAct SemanticActionSet
- disableLAC bool
- onError bool
- shiftCount int
- synErrs []*SyntaxError
-}
-
-func NewParser(toks TokenStream, gram Grammar, opts ...ParserOption) (*Parser, error) {
- p := &Parser{
- toks: toks,
- gram: gram,
- stateStack: &stateStack{},
- }
-
- for _, opt := range opts {
- err := opt(p)
- if err != nil {
- return nil, err
- }
- }
-
- return p, nil
-}
-
-func (p *Parser) Parse() error {
- p.stateStack.push(p.gram.InitialState())
- tok, err := p.nextToken()
- if err != nil {
- return err
- }
-
-ACTION_LOOP:
- for {
- act := p.lookupAction(tok)
-
- switch {
- case act < 0: // Shift
- nextState := act * -1
-
- recovered := false
- if p.onError {
- p.shiftCount++
-
- // When the parser performs shift three times, the parser recovers from the error state.
- if p.shiftCount >= 3 {
- p.onError = false
- p.shiftCount = 0
- recovered = true
- }
- }
-
- p.shift(nextState)
-
- if p.semAct != nil {
- p.semAct.Shift(tok, recovered)
- }
-
- tok, err = p.nextToken()
- if err != nil {
- return err
- }
- case act > 0: // Reduce
- prodNum := act
-
- recovered := false
- if p.onError && p.gram.RecoverProduction(prodNum) {
- p.onError = false
- p.shiftCount = 0
- recovered = true
- }
-
- accepted := p.reduce(prodNum)
- if accepted {
- if p.semAct != nil {
- p.semAct.Accept()
- }
-
- return nil
- }
-
- if p.semAct != nil {
- p.semAct.Reduce(prodNum, recovered)
- }
- default: // Error
- if p.onError {
- tok, err = p.nextToken()
- if err != nil {
- return err
- }
- if tok.EOF() {
- if p.semAct != nil {
- p.semAct.MissError(tok)
- }
-
- return nil
- }
-
- continue ACTION_LOOP
- }
-
- row, col := tok.Position()
- p.synErrs = append(p.synErrs, &SyntaxError{
- Row: row,
- Col: col,
- Message: "unexpected token",
- Token: tok,
- ExpectedTerminals: p.searchLookahead(p.stateStack.top()),
- })
-
- count, ok := p.trapError()
- if !ok {
- if p.semAct != nil {
- p.semAct.MissError(tok)
- }
-
- return nil
- }
-
- p.onError = true
- p.shiftCount = 0
-
- act, err := p.lookupActionOnError()
- if err != nil {
- return err
- }
-
- p.shift(act * -1)
-
- if p.semAct != nil {
- p.semAct.TrapAndShiftError(tok, count)
- }
- }
- }
-}
-
-// validateLookahead validates whether `term` is a valid lookahead in the current context. When `term` is valid,
-// this method returns `true`.
-func (p *Parser) validateLookahead(term int) bool {
- p.stateStack.enableExploratoryMode()
- defer p.stateStack.disableExploratoryMode()
-
- for {
- act := p.gram.Action(p.stateStack.topExploratorily(), term)
-
- switch {
- case act < 0: // Shift
- return true
- case act > 0: // Reduce
- prodNum := act
-
- lhs := p.gram.LHS(prodNum)
- if lhs == p.gram.LHS(p.gram.StartProduction()) {
- return true
- }
- n := p.gram.AlternativeSymbolCount(prodNum)
- p.stateStack.popExploratorily(n)
- state := p.gram.GoTo(p.stateStack.topExploratorily(), lhs)
- p.stateStack.pushExploratorily(state)
- default: // Error
- return false
- }
- }
-}
-
-func (p *Parser) nextToken() (VToken, error) {
- for {
- // We don't have to check whether the token is invalid because the kind ID of the invalid token is 0,
- // and the parsing table doesn't have an entry corresponding to the kind ID 0. Thus we can detect
- // a syntax error because the parser cannot find an entry corresponding to the invalid token.
- tok, err := p.toks.Next()
- if err != nil {
- return nil, err
- }
-
- if p.gram.SkipTerminal(tok.TerminalID()) {
- continue
- }
-
- return tok, nil
- }
-}
-
-func (p *Parser) tokenToTerminal(tok VToken) int {
- if tok.EOF() {
- return p.gram.EOF()
- }
-
- return tok.TerminalID()
-}
-
-func (p *Parser) lookupAction(tok VToken) int {
- if !p.disableLAC {
- term := p.tokenToTerminal(tok)
- if !p.validateLookahead(term) {
- return 0
- }
- }
-
- return p.gram.Action(p.stateStack.top(), p.tokenToTerminal(tok))
-}
-
-func (p *Parser) lookupActionOnError() (int, error) {
- act := p.gram.Action(p.stateStack.top(), p.gram.Error())
- if act >= 0 {
- return 0, fmt.Errorf("an entry must be a shift action by the error symbol; entry: %v, state: %v, symbol: %v", act, p.stateStack.top(), p.gram.Terminal(p.gram.Error()))
- }
-
- return act, nil
-}
-
-func (p *Parser) shift(nextState int) {
- p.stateStack.push(nextState)
-}
-
-func (p *Parser) reduce(prodNum int) bool {
- lhs := p.gram.LHS(prodNum)
- if lhs == p.gram.LHS(p.gram.StartProduction()) {
- return true
- }
- n := p.gram.AlternativeSymbolCount(prodNum)
- p.stateStack.pop(n)
- nextState := p.gram.GoTo(p.stateStack.top(), lhs)
- p.stateStack.push(nextState)
- return false
-}
-
-func (p *Parser) trapError() (int, bool) {
- count := 0
- for {
- if p.gram.ErrorTrapperState(p.stateStack.top()) {
- return count, true
- }
-
- if p.stateStack.top() != p.gram.InitialState() {
- p.stateStack.pop(1)
- count++
- } else {
- return 0, false
- }
- }
-}
-
-func (p *Parser) SyntaxErrors() []*SyntaxError {
- return p.synErrs
-}
-
-func (p *Parser) searchLookahead(state int) []string {
- kinds := []string{}
- termCount := p.gram.TerminalCount()
- for term := 0; term < termCount; term++ {
- if p.disableLAC {
- if p.gram.Action(p.stateStack.top(), term) == 0 {
- continue
- }
- } else {
- if !p.validateLookahead(term) {
- continue
- }
- }
-
- // We don't add the error symbol to the look-ahead symbols because users cannot input the error symbol
- // intentionally.
- if term == p.gram.Error() {
- continue
- }
-
- kinds = append(kinds, p.gram.Terminal(term))
- }
-
- return kinds
-}
-
-type stateStack struct {
- items []int
- itemsExp []int
-}
-
-func (s *stateStack) enableExploratoryMode() {
- s.itemsExp = make([]int, len(s.items))
- copy(s.itemsExp, s.items)
-}
-
-func (s *stateStack) disableExploratoryMode() {
- s.itemsExp = nil
-}
-
-func (s *stateStack) top() int {
- return s.items[len(s.items)-1]
-}
-
-func (s *stateStack) topExploratorily() int {
- return s.itemsExp[len(s.itemsExp)-1]
-}
-
-func (s *stateStack) push(state int) {
- s.items = append(s.items, state)
-}
-
-func (s *stateStack) pushExploratorily(state int) {
- s.itemsExp = append(s.itemsExp, state)
-}
-
-func (s *stateStack) pop(n int) {
- s.items = s.items[:len(s.items)-n]
-}
-
-func (s *stateStack) popExploratorily(n int) {
- s.itemsExp = s.itemsExp[:len(s.itemsExp)-n]
-}
diff --git a/driver/parser/parser_test.go b/driver/parser/parser_test.go
deleted file mode 100644
index cdfd922..0000000
--- a/driver/parser/parser_test.go
+++ /dev/null
@@ -1,833 +0,0 @@
-package parser
-
-import (
- "fmt"
- "strings"
- "testing"
-
- "grammar"
- "spec/grammar/parser"
-)
-
-func termNode(kind string, text string, children ...*Node) *Node {
- return &Node{
- Type: NodeTypeTerminal,
- KindName: kind,
- Text: text,
- Children: children,
- }
-}
-
-func errorNode() *Node {
- return &Node{
- Type: NodeTypeError,
- KindName: "error",
- }
-}
-
-func nonTermNode(kind string, children ...*Node) *Node {
- return &Node{
- Type: NodeTypeNonTerminal,
- KindName: kind,
- Children: children,
- }
-}
-
-func TestParser_Parse(t *testing.T) {
- tests := []struct {
- specSrc string
- src string
- synErr bool
- cst *Node
- ast *Node
- }{
- {
- specSrc: `
-#name test;
-
-expr
- : expr add term
- | term
- ;
-term
- : term mul factor
- | factor
- ;
-factor
- : l_paren expr r_paren
- | id
- ;
-
-add
- : '+';
-mul
- : '*';
-l_paren
- : '(';
-r_paren
- : ')';
-id
- : "[A-Za-z_][0-9A-Za-z_]*";
-`,
- src: `(a+(b+c))*d+e`,
- cst: nonTermNode("expr",
- nonTermNode("expr",
- nonTermNode("term",
- nonTermNode("term",
- nonTermNode("factor",
- termNode("l_paren", "("),
- nonTermNode("expr",
- nonTermNode("expr",
- nonTermNode("term",
- nonTermNode("factor",
- termNode("id", "a"),
- ),
- ),
- ),
- termNode("add", "+"),
- nonTermNode("term",
- nonTermNode("factor",
- termNode("l_paren", "("),
- nonTermNode("expr",
- nonTermNode("expr",
- nonTermNode("term",
- nonTermNode("factor",
- termNode("id", "b"),
- ),
- ),
- ),
- termNode("add", "+"),
- nonTermNode("term",
- nonTermNode("factor",
- termNode("id", "c"),
- ),
- ),
- ),
- termNode("r_paren", ")"),
- ),
- ),
- ),
- termNode("r_paren", ")"),
- ),
- ),
- termNode("mul", "*"),
- nonTermNode("factor",
- termNode("id", "d"),
- ),
- ),
- ),
- termNode("add", "+"),
- nonTermNode("term",
- nonTermNode("factor",
- termNode("id", "e"),
- ),
- ),
- ),
- },
- // Fragments (\f{}), code point expressions (\u{}), and character property expressions (\p{}) are
- // not allowed in string literals.
- {
- specSrc: `
-#name test;
-
-s
- : a b c
- ;
-
-a
- : '\f{foo}';
-b
- : '\u{0000}';
-c
- : '\p{gc=Letter}';
-`,
- src: `\f{foo}\u{0000}\p{gc=Letter}`,
- cst: nonTermNode("s",
- termNode("a", `\f{foo}`),
- termNode("b", `\u{0000}`),
- termNode("c", `\p{gc=Letter}`),
- ),
- },
- // The driver can reduce productions that have the empty alternative and can generate a CST (and AST) node.
- {
- specSrc: `
-#name test;
-
-s
- : foo bar
- ;
-foo
- :
- ;
-bar
- : bar_text
- |
- ;
-bar_text: "bar";
-`,
- src: ``,
- cst: nonTermNode("s",
- nonTermNode("foo"),
- nonTermNode("bar"),
- ),
- },
- // The driver can reduce productions that have the empty alternative and can generate a CST (and AST) node.
- {
- specSrc: `
-#name test;
-
-s
- : foo bar
- ;
-foo
- :
- ;
-bar
- : bar_text
- |
- ;
-
-bar_text
- : "bar";
-`,
- src: `bar`,
- cst: nonTermNode("s",
- nonTermNode("foo"),
- nonTermNode("bar",
- termNode("bar_text", "bar"),
- ),
- ),
- },
- // A production can have multiple alternative productions.
- {
- specSrc: `
-#name test;
-
-#prec (
- #assign $uminus
- #left mul div
- #left add sub
-);
-
-expr
- : expr add expr
- | expr sub expr
- | expr mul expr
- | expr div expr
- | int
- | sub int #prec $uminus // This 'sub' means the unary minus symbol.
- ;
-
-int
- : "0|[1-9][0-9]*";
-add
- : '+';
-sub
- : '-';
-mul
- : '*';
-div
- : '/';
-`,
- src: `-1*-2+3-4/5`,
- ast: nonTermNode("expr",
- nonTermNode("expr",
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("sub", "-"),
- termNode("int", "1"),
- ),
- termNode("mul", "*"),
- nonTermNode("expr",
- termNode("sub", "-"),
- termNode("int", "2"),
- ),
- ),
- termNode("add", "+"),
- nonTermNode("expr",
- termNode("int", "3"),
- ),
- ),
- termNode("sub", "-"),
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("int", "4"),
- ),
- termNode("div", "/"),
- nonTermNode("expr",
- termNode("int", "5"),
- ),
- ),
- ),
- },
- // A lexical production can have multiple production directives.
- {
- specSrc: `
-#name test;
-
-s
- : push_a push_b pop pop
- ;
-
-push_a #mode default #push a
- : '->a';
-push_b #mode a #push b
- : '->b';
-pop #mode a b #pop
- : '<-';
-`,
- src: `->a->b<-<-`,
- ast: nonTermNode("s",
- termNode("push_a", "->a"),
- termNode("push_b", "->b"),
- termNode("pop", "<-"),
- termNode("pop", "<-"),
- ),
- },
- {
- specSrc: `
-#name test;
-
-mode_tran_seq
- : mode_tran_seq mode_tran
- | mode_tran
- ;
-mode_tran
- : push_m1
- | push_m2
- | pop_m1
- | pop_m2
- ;
-
-push_m1 #push m1
- : "->";
-push_m2 #mode m1 #push m2
- : "-->";
-pop_m1 #mode m1 #pop
- : "<-";
-pop_m2 #mode m2 #pop
- : "<--";
-whitespace #mode default m1 m2 #skip
- : "\u{0020}+";
-`,
- src: ` -> --> <-- <- `,
- },
- {
- specSrc: `
-#name test;
-
-s
- : foo bar
- ;
-
-foo
- : "foo";
-bar #mode default
- : "bar";
-`,
- src: `foobar`,
- },
- // When #push and #pop are applied to the same symbol, #pop will run first, then #push.
- {
- specSrc: `
-#name test;
-
-s
- : foo bar baz
- ;
-
-foo #push m1
- : 'foo';
-bar #mode m1 #pop #push m2
- : 'bar';
-baz #mode m2
- : 'baz';
-`,
- src: `foobarbaz`,
- ast: nonTermNode("s",
- termNode("foo", "foo"),
- termNode("bar", "bar"),
- termNode("baz", "baz"),
- ),
- },
- // When #push and #pop are applied to the same symbol, #pop will run first, then #push, even if #push appears first
- // in a definition. That is, the order in which #push and #pop appear in grammar has nothing to do with the order in which
- // they are executed.
- {
- specSrc: `
-#name test;
-
-s
- : foo bar baz
- ;
-
-foo #push m1
- : 'foo';
-bar #mode m1 #push m2 #pop
- : 'bar';
-baz #mode m2
- : 'baz';
-`,
- src: `foobarbaz`,
- ast: nonTermNode("s",
- termNode("foo", "foo"),
- termNode("bar", "bar"),
- termNode("baz", "baz"),
- ),
- },
- // The parser can skips specified tokens.
- {
- specSrc: `
-#name test;
-
-s
- : foo bar
- ;
-
-foo
- : "foo";
-bar
- : "bar";
-white_space #skip
- : "[\u{0009}\u{0020}]+";
-`,
- src: `foo bar`,
- },
- // A grammar can contain fragments.
- {
- specSrc: `
-#name test;
-
-s
- : tagline
- ;
-tagline
- : "\f{words} IS OUT THERE.";
-fragment words
- : "[A-Za-z\u{0020}]+";
-`,
- src: `THE TRUTH IS OUT THERE.`,
- },
- // A grammar can contain ast actions.
- {
- specSrc: `
-#name test;
-
-list
- : l_bracket elems r_bracket #ast elems...
- ;
-elems
- : elems comma id #ast elems... id
- | id
- ;
-
-whitespace #skip
- : "\u{0020}+";
-l_bracket
- : '[';
-r_bracket
- : ']';
-comma
- : ',';
-id
- : "[A-Za-z]+";
-`,
- src: `[Byers, Frohike, Langly]`,
- cst: nonTermNode("list",
- termNode("x_1", "["),
- nonTermNode("elems",
- nonTermNode("elems",
- nonTermNode("elems",
- termNode("id", "Byers"),
- ),
- termNode("x_3", ","),
- termNode("id", "Frohike"),
- ),
- termNode("x_3", ","),
- termNode("id", "Langly"),
- ),
- termNode("x_2", "]"),
- ),
- ast: nonTermNode("list",
- termNode("id", "Byers"),
- termNode("id", "Frohike"),
- termNode("id", "Langly"),
- ),
- },
- // The '...' operator can expand child nodes.
- {
- specSrc: `
-#name test;
-
-s
- : a #ast a...
- ;
-a
- : a comma foo #ast a... foo
- | foo
- ;
-
-comma
- : ',';
-foo
- : 'foo';
-`,
- src: `foo,foo,foo`,
- ast: nonTermNode("s",
- termNode("foo", "foo"),
- termNode("foo", "foo"),
- termNode("foo", "foo"),
- ),
- },
- // The '...' operator also can applied to an element having no children.
- {
- specSrc: `
-#name test;
-
-s
- : a semi_colon #ast a...
- ;
-a
- :
- ;
-
-semi_colon
- : ';';
-`,
- src: `;`,
- ast: nonTermNode("s"),
- },
- // A label can be a parameter of #ast directive.
- {
- specSrc: `
-#name test;
-
-#prec (
- #left add sub
-);
-
-expr
- : expr@lhs add expr@rhs #ast add lhs rhs
- | expr@lhs sub expr@rhs #ast sub lhs rhs
- | num
- ;
-
-add
- : '+';
-sub
- : '-';
-num
- : "0|[1-9][0-9]*";
-`,
- src: `1+2-3`,
- ast: nonTermNode("expr",
- termNode("sub", "-"),
- nonTermNode("expr",
- termNode("add", "+"),
- nonTermNode("expr",
- termNode("num", "1"),
- ),
- nonTermNode("expr",
- termNode("num", "2"),
- ),
- ),
- nonTermNode("expr",
- termNode("num", "3"),
- ),
- ),
- },
- // An AST can contain a symbol name, even if the symbol has a label. That is, unused labels are allowed.
- {
- specSrc: `
-#name test;
-
-s
- : foo@x semi_colon #ast foo
- ;
-
-semi_colon
- : ';';
-foo
- : 'foo';
-`,
- src: `foo;`,
- ast: nonTermNode("s",
- termNode("foo", "foo"),
- ),
- },
- // A production has the same precedence and associativity as the right-most terminal symbol.
- {
- specSrc: `
-#name test;
-
-#prec (
- #left add
-);
-
-expr
- : expr add expr // This alternative has the same precedence and associativiry as 'add'.
- | int
- ;
-
-ws #skip
- : "[\u{0009}\u{0020}]+";
-int
- : "0|[1-9][0-9]*";
-add
- : '+';
-`,
- // This source is recognized as the following structure because the production `expr → expr add expr` has the same
- // precedence and associativity as the symbol 'add'.
- //
- // ((1+2)+3)
- //
- // If the symbol doesn't have the precedence and left associativity, the production also doesn't have the precedence
- // and associativity and this source will be recognized as the following structure.
- //
- // (1+(2+3))
- src: `1+2+3`,
- ast: nonTermNode("expr",
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("int", "1"),
- ),
- termNode("add", "+"),
- nonTermNode("expr",
- termNode("int", "2"),
- ),
- ),
- termNode("add", "+"),
- nonTermNode("expr",
- termNode("int", "3"),
- ),
- ),
- },
- // The 'prec' directive can set precedence of a production.
- {
- specSrc: `
-#name test;
-
-#prec (
- #assign $uminus
- #left mul div
- #left add sub
-);
-
-expr
- : expr add expr
- | expr sub expr
- | expr mul expr
- | expr div expr
- | int
- | sub int #prec $uminus // This 'sub' means a unary minus symbol.
- ;
-
-ws #skip
- : "[\u{0009}\u{0020}]+";
-int
- : "0|[1-9][0-9]*";
-add
- : '+';
-sub
- : '-';
-mul
- : '*';
-div
- : '/';
-`,
- // This source is recognized as the following structure because the production `expr → sub expr`
- // has the `#prec mul` directive and has the same precedence of the symbol `mul`.
- //
- // (((-1) * 20) / 5)
- //
- // If the production doesn't have the `#prec` directive, this source will be recognized as
- // the following structure.
- //
- // (- ((1 * 20) / 5))
- src: `-1*20/5`,
- cst: nonTermNode("expr",
- nonTermNode("expr",
- nonTermNode("expr",
- termNode("sub", "-"),
- termNode("int", "1"),
- ),
- termNode("mul", "*"),
- nonTermNode("expr",
- termNode("int", "20"),
- ),
- ),
- termNode("div", "/"),
- nonTermNode("expr",
- termNode("int", "5"),
- ),
- ),
- },
- // The grammar can contain the 'error' symbol.
- {
- specSrc: `
-#name test;
-
-s
- : id id id semi_colon
- | error semi_colon
- ;
-
-ws #skip
- : "[\u{0009}\u{0020}]+";
-semi_colon
- : ';';
-id
- : "[A-Za-z_]+";
-`,
- src: `foo bar baz ;`,
- },
- // The 'error' symbol can appear in an #ast directive.
- {
- specSrc: `
-#name test;
-
-s
- : foo semi_colon
- | error semi_colon #ast error
- ;
-
-semi_colon
- : ';';
-foo
- : 'foo';
-`,
- src: `bar;`,
- synErr: true,
- ast: nonTermNode("s",
- errorNode(),
- ),
- },
- // The 'error' symbol can have a label, and an #ast can reference it.
- {
- specSrc: `
-#name test;
-
-s
- : foo semi_colon
- | error@e semi_colon #ast e
- ;
-
-semi_colon
- : ';';
-foo
- : 'foo';
-`,
- src: `bar;`,
- synErr: true,
- ast: nonTermNode("s",
- errorNode(),
- ),
- },
- // The grammar can contain the 'recover' directive.
- {
- specSrc: `
-#name test;
-
-seq
- : seq elem
- | elem
- ;
-elem
- : id id id semi_colon
- | error semi_colon #recover
- ;
-
-ws #skip
- : "[\u{0009}\u{0020}]+";
-semi_colon
- : ';';
-id
- : "[A-Za-z_]+";
-`,
- src: `a b c ; d e f ;`,
- },
- // The same label can be used between different alternatives.
- {
- specSrc: `
-#name test;
-
-s
- : foo@x bar
- | foo@x
- ;
-
-foo: 'foo';
-bar: 'bar';
-`,
- src: `foo`,
- },
- }
-
- for i, tt := range tests {
- t.Run(fmt.Sprintf("#%v", i), func(t *testing.T) {
- ast, err := parser.Parse(strings.NewReader(tt.specSrc))
- if err != nil {
- t.Fatal(err)
- }
-
- b := grammar.GrammarBuilder{
- AST: ast,
- }
- cg, _, err := b.Build()
- if err != nil {
- t.Fatal(err)
- }
-
- toks, err := NewTokenStream(cg, strings.NewReader(tt.src))
- if err != nil {
- t.Fatal(err)
- }
-
- gram := NewGrammar(cg)
- tb := NewDefaultSyntaxTreeBuilder()
- var opt []ParserOption
- switch {
- case tt.ast != nil:
- opt = append(opt, SemanticAction(NewASTActionSet(gram, tb)))
- case tt.cst != nil:
- opt = append(opt, SemanticAction(NewCSTActionSet(gram, tb)))
- }
- p, err := NewParser(toks, gram, opt...)
- if err != nil {
- t.Fatal(err)
- }
-
- err = p.Parse()
- if err != nil {
- t.Fatal(err)
- }
-
- if !tt.synErr && len(p.SyntaxErrors()) > 0 {
- for _, synErr := range p.SyntaxErrors() {
- t.Fatalf("unexpected syntax errors occurred: %v", synErr)
- }
- }
-
- switch {
- case tt.ast != nil:
- testTree(t, tb.Tree(), tt.ast)
- case tt.cst != nil:
- testTree(t, tb.Tree(), tt.cst)
- }
- })
- }
-}
-
-func testTree(t *testing.T, node, expected *Node) {
- t.Helper()
-
- if node.Type != expected.Type || node.KindName != expected.KindName || node.Text != expected.Text {
- t.Fatalf("unexpected node; want: %+v, got: %+v", expected, node)
- }
- if len(node.Children) != len(expected.Children) {
- t.Fatalf("unexpected children; want: %v, got: %v", len(expected.Children), len(node.Children))
- }
- for i, c := range node.Children {
- testTree(t, c, expected.Children[i])
- }
-}
diff --git a/driver/parser/semantic_action.go b/driver/parser/semantic_action.go
deleted file mode 100644
index 6bb78cf..0000000
--- a/driver/parser/semantic_action.go
+++ /dev/null
@@ -1,371 +0,0 @@
-package parser
-
-import (
- "encoding/json"
- "fmt"
- "io"
- "strconv"
-)
-
-// SemanticActionSet is a set of semantic actions a parser calls.
-type SemanticActionSet interface {
- // Shift runs when the parser shifts a symbol onto a state stack. `tok` is a token corresponding to the symbol.
- // When the parser recovered from an error state by shifting the token, `recovered` is true.
- Shift(tok VToken, recovered bool)
-
- // Reduce runs when the parser reduces an RHS of a production to its LHS. `prodNum` is a number of the production.
- // When the parser recovered from an error state by reducing the production, `recovered` is true.
- Reduce(prodNum int, recovered bool)
-
- // Accept runs when the parser accepts an input.
- Accept()
-
- // TrapAndShiftError runs when the parser traps a syntax error and shifts a error symbol onto the state stack.
- // `cause` is a token that caused a syntax error. `popped` is the number of frames that the parser discards
- // from the state stack.
- // Unlike `Shift` function, this function doesn't take a token to be shifted as an argument because a token
- // corresponding to the error symbol doesn't exist.
- TrapAndShiftError(cause VToken, popped int)
-
- // MissError runs when the parser fails to trap a syntax error. `cause` is a token that caused a syntax error.
- MissError(cause VToken)
-}
-
-var _ SemanticActionSet = &SyntaxTreeActionSet{}
-
-// SyntaxTreeNode is a node of a syntax tree. A node type used in SyntaxTreeActionSet must implement SyntaxTreeNode interface.
-type SyntaxTreeNode interface {
- // ChildCount returns a child count of a node. A parser calls this method to know the child count to be expanded by an `#ast`
- // directive with `...` operator.
- ChildCount() int
-
- // ExpandChildren returns children of a node. A parser calls this method to fetch the children to be expanded by an `#ast`
- // directive with `...` operator.
- ExpandChildren() []SyntaxTreeNode
-}
-
-var _ SyntaxTreeNode = &Node{}
-
-// SyntaxTreeBuilder allows you to construct a syntax tree containing arbitrary user-defined node types.
-// The parser uses SyntaxTreeBuilder interface as a part of semantic actions via SyntaxTreeActionSet interface.
-type SyntaxTreeBuilder interface {
- Shift(kindName string, tok VToken) SyntaxTreeNode
- ShiftError(kindName string) SyntaxTreeNode
- Reduce(kindName string, children []SyntaxTreeNode) SyntaxTreeNode
- Accept(f SyntaxTreeNode)
-}
-
-var _ SyntaxTreeBuilder = &DefaultSyntaxTreeBuilder{}
-
-// DefaultSyntaxTreeBuilder is a implementation of SyntaxTreeBuilder.
-type DefaultSyntaxTreeBuilder struct {
- tree *Node
-}
-
-// NewDefaultSyntaxTreeBuilder returns a new DefaultSyntaxTreeBuilder.
-func NewDefaultSyntaxTreeBuilder() *DefaultSyntaxTreeBuilder {
- return &DefaultSyntaxTreeBuilder{}
-}
-
-// Shift is a implementation of SyntaxTreeBuilder.Shift.
-func (b *DefaultSyntaxTreeBuilder) Shift(kindName string, tok VToken) SyntaxTreeNode {
- bytePos, byteLen := tok.BytePosition()
- row, col := tok.Position()
- return &Node{
- Type: NodeTypeTerminal,
- KindName: kindName,
- Text: string(tok.Lexeme()),
- BytePos: bytePos,
- ByteLen: byteLen,
- Row: row,
- Col: col,
- }
-}
-
-// ShiftError is a implementation of SyntaxTreeBuilder.ShiftError.
-func (b *DefaultSyntaxTreeBuilder) ShiftError(kindName string) SyntaxTreeNode {
- return &Node{
- Type: NodeTypeError,
- KindName: kindName,
- }
-}
-
-// Reduce is a implementation of SyntaxTreeBuilder.Reduce.
-func (b *DefaultSyntaxTreeBuilder) Reduce(kindName string, children []SyntaxTreeNode) SyntaxTreeNode {
- cNodes := make([]*Node, len(children))
- for i, c := range children {
- cNodes[i] = c.(*Node)
- }
- return &Node{
- Type: NodeTypeNonTerminal,
- KindName: kindName,
- Children: cNodes,
- }
-}
-
-// Accept is a implementation of SyntaxTreeBuilder.Accept.
-func (b *DefaultSyntaxTreeBuilder) Accept(f SyntaxTreeNode) {
- b.tree = f.(*Node)
-}
-
-// Tree returns a syntax tree when the parser has accepted an input. If a syntax error occurs, the return value is nil.
-func (b *DefaultSyntaxTreeBuilder) Tree() *Node {
- return b.tree
-}
-
-// SyntaxTreeActionSet is a implementation of SemanticActionSet interface and constructs a syntax tree.
-type SyntaxTreeActionSet struct {
- gram Grammar
- builder SyntaxTreeBuilder
- semStack *semanticStack
- disableASTAction bool
-}
-
-// NewASTActionSet returns a new SyntaxTreeActionSet that constructs an AST (Abstract Syntax Tree).
-// When grammar `gram` contains `#ast` directives, the new SyntaxTreeActionSet this function returns interprets them.
-func NewASTActionSet(gram Grammar, builder SyntaxTreeBuilder) *SyntaxTreeActionSet {
- return &SyntaxTreeActionSet{
- gram: gram,
- builder: builder,
- semStack: newSemanticStack(),
- }
-}
-
-// NewCSTTActionSet returns a new SyntaxTreeActionSet that constructs a CST (Concrete Syntax Tree).
-// Even if grammar `gram` contains `#ast` directives, the new SyntaxTreeActionSet this function returns ignores them.
-func NewCSTActionSet(gram Grammar, builder SyntaxTreeBuilder) *SyntaxTreeActionSet {
- return &SyntaxTreeActionSet{
- gram: gram,
- builder: builder,
- semStack: newSemanticStack(),
- disableASTAction: true,
- }
-}
-
-// Shift is a implementation of SemanticActionSet.Shift method.
-func (a *SyntaxTreeActionSet) Shift(tok VToken, recovered bool) {
- term := a.tokenToTerminal(tok)
- a.semStack.push(a.builder.Shift(a.gram.Terminal(term), tok))
-}
-
-// Reduce is a implementation of SemanticActionSet.Reduce method.
-func (a *SyntaxTreeActionSet) Reduce(prodNum int, recovered bool) {
- lhs := a.gram.LHS(prodNum)
-
- // When an alternative is empty, `n` will be 0, and `handle` will be empty slice.
- n := a.gram.AlternativeSymbolCount(prodNum)
- handle := a.semStack.pop(n)
-
- var astAct []int
- if !a.disableASTAction {
- astAct = a.gram.ASTAction(prodNum)
- }
- var children []SyntaxTreeNode
- if astAct != nil {
- // Count the number of children in advance to avoid frequent growth in a slice for children.
- {
- l := 0
- for _, e := range astAct {
- if e > 0 {
- l++
- } else {
- offset := e*-1 - 1
- l += handle[offset].ChildCount()
- }
- }
-
- children = make([]SyntaxTreeNode, l)
- }
-
- p := 0
- for _, e := range astAct {
- if e > 0 {
- offset := e - 1
- children[p] = handle[offset]
- p++
- } else {
- offset := e*-1 - 1
- for _, c := range handle[offset].ExpandChildren() {
- children[p] = c
- p++
- }
- }
- }
- } else {
- // If an alternative has no AST action, a driver generates
- // a node with the same structure as a CST.
- children = handle
- }
-
- a.semStack.push(a.builder.Reduce(a.gram.NonTerminal(lhs), children))
-}
-
-// Accept is a implementation of SemanticActionSet.Accept method.
-func (a *SyntaxTreeActionSet) Accept() {
- top := a.semStack.pop(1)
- a.builder.Accept(top[0])
-}
-
-// TrapAndShiftError is a implementation of SemanticActionSet.TrapAndShiftError method.
-func (a *SyntaxTreeActionSet) TrapAndShiftError(cause VToken, popped int) {
- a.semStack.pop(popped)
- a.semStack.push(a.builder.ShiftError(a.gram.Terminal(a.gram.Error())))
-}
-
-// MissError is a implementation of SemanticActionSet.MissError method.
-func (a *SyntaxTreeActionSet) MissError(cause VToken) {
-}
-
-func (a *SyntaxTreeActionSet) tokenToTerminal(tok VToken) int {
- if tok.EOF() {
- return a.gram.EOF()
- }
-
- return tok.TerminalID()
-}
-
-type semanticStack struct {
- frames []SyntaxTreeNode
-}
-
-func newSemanticStack() *semanticStack {
- return &semanticStack{
- frames: make([]SyntaxTreeNode, 0, 100),
- }
-}
-
-func (s *semanticStack) push(f SyntaxTreeNode) {
- s.frames = append(s.frames, f)
-}
-
-func (s *semanticStack) pop(n int) []SyntaxTreeNode {
- fs := s.frames[len(s.frames)-n:]
- s.frames = s.frames[:len(s.frames)-n]
-
- return fs
-}
-
-type NodeType int
-
-const (
- NodeTypeError = 0
- NodeTypeTerminal = 1
- NodeTypeNonTerminal = 2
-)
-
-// Node is a implementation of SyntaxTreeNode interface.
-type Node struct {
- Type NodeType
- KindName string
- Text string
- BytePos int
- ByteLen int
- Row int
- Col int
- Children []*Node
-}
-
-func (n *Node) MarshalJSON() ([]byte, error) {
- switch n.Type {
- case NodeTypeError:
- return json.Marshal(struct {
- Type NodeType `json:"type"`
- KindName string `json:"kind_name"`
- }{
- Type: n.Type,
- KindName: n.KindName,
- })
- case NodeTypeTerminal:
- if n.KindName == "" {
- return json.Marshal(struct {
- Type NodeType `json:"type"`
- Text string `json:"text"`
- Row int `json:"row"`
- Col int `json:"col"`
- }{
- Type: n.Type,
- Text: n.Text,
- Row: n.Row,
- Col: n.Col,
- })
- }
- return json.Marshal(struct {
- Type NodeType `json:"type"`
- KindName string `json:"kind_name"`
- Text string `json:"text"`
- Row int `json:"row"`
- Col int `json:"col"`
- }{
- Type: n.Type,
- KindName: n.KindName,
- Text: n.Text,
- Row: n.Row,
- Col: n.Col,
- })
- case NodeTypeNonTerminal:
- return json.Marshal(struct {
- Type NodeType `json:"type"`
- KindName string `json:"kind_name"`
- Children []*Node `json:"children"`
- }{
- Type: n.Type,
- KindName: n.KindName,
- Children: n.Children,
- })
- default:
- return nil, fmt.Errorf("invalid node type: %v", n.Type)
- }
-}
-
-// ChildCount is a implementation of SyntaxTreeNode.ChildCount.
-func (n *Node) ChildCount() int {
- return len(n.Children)
-}
-
-// ExpandChildren is a implementation of SyntaxTreeNode.ExpandChildren.
-func (n *Node) ExpandChildren() []SyntaxTreeNode {
- fs := make([]SyntaxTreeNode, len(n.Children))
- for i, n := range n.Children {
- fs[i] = n
- }
- return fs
-}
-
-// PrintTree prints a syntax tree whose root is `node`.
-func PrintTree(w io.Writer, node *Node) {
- printTree(w, node, "", "")
-}
-
-func printTree(w io.Writer, node *Node, ruledLine string, childRuledLinePrefix string) {
- if node == nil {
- return
- }
-
- switch node.Type {
- case NodeTypeError:
- fmt.Fprintf(w, "%v%v\n", ruledLine, node.KindName)
- case NodeTypeTerminal:
- fmt.Fprintf(w, "%v%v %v\n", ruledLine, node.KindName, strconv.Quote(node.Text))
- case NodeTypeNonTerminal:
- fmt.Fprintf(w, "%v%v\n", ruledLine, node.KindName)
-
- num := len(node.Children)
- for i, child := range node.Children {
- var line string
- if num > 1 && i < num-1 {
- line = "├─ "
- } else {
- line = "└─ "
- }
-
- var prefix string
- if i >= num-1 {
- prefix = " "
- } else {
- prefix = "│ "
- }
-
- printTree(w, child, childRuledLinePrefix+line, childRuledLinePrefix+prefix)
- }
- }
-}
diff --git a/driver/parser/semantic_action_test.go b/driver/parser/semantic_action_test.go
deleted file mode 100644
index 8c224e2..0000000
--- a/driver/parser/semantic_action_test.go
+++ /dev/null
@@ -1,227 +0,0 @@
-package parser
-
-import (
- "fmt"
- "strings"
- "testing"
-
- "grammar"
- spec "spec/grammar"
- "spec/grammar/parser"
-)
-
-type testSemAct struct {
- gram *spec.CompiledGrammar
- actLog []string
-}
-
-func (a *testSemAct) Shift(tok VToken, recovered bool) {
- t := a.gram.Syntactic.Terminals[tok.TerminalID()]
- if recovered {
- a.actLog = append(a.actLog, fmt.Sprintf("shift/%v/recovered", t))
- } else {
- a.actLog = append(a.actLog, fmt.Sprintf("shift/%v", t))
- }
-}
-
-func (a *testSemAct) Reduce(prodNum int, recovered bool) {
- lhsSym := a.gram.Syntactic.LHSSymbols[prodNum]
- lhsText := a.gram.Syntactic.NonTerminals[lhsSym]
- if recovered {
- a.actLog = append(a.actLog, fmt.Sprintf("reduce/%v/recovered", lhsText))
- } else {
- a.actLog = append(a.actLog, fmt.Sprintf("reduce/%v", lhsText))
- }
-}
-
-func (a *testSemAct) Accept() {
- a.actLog = append(a.actLog, "accept")
-}
-
-func (a *testSemAct) TrapAndShiftError(cause VToken, popped int) {
- a.actLog = append(a.actLog, fmt.Sprintf("trap/%v/shift/error", popped))
-}
-
-func (a *testSemAct) MissError(cause VToken) {
- a.actLog = append(a.actLog, "miss")
-}
-
-func TestParserWithSemanticAction(t *testing.T) {
- specSrcWithErrorProd := `
-#name test;
-
-seq
- : seq elem semicolon
- | elem semicolon
- | error star star semicolon
- | error semicolon #recover
- ;
-elem
- : char char char
- ;
-
-ws #skip
- : "[\u{0009}\u{0020}]+";
-semicolon
- : ';';
-star
- : '*';
-char
- : "[a-z]";
-`
-
- specSrcWithoutErrorProd := `
-#name test;
-
-seq
- : seq elem semicolon
- | elem semicolon
- ;
-elem
- : char char char
- ;
-
-ws #skip
- : "[\u{0009}\u{0020}]+";
-semicolon
- : ';';
-char
- : "[a-z]";
-`
-
- tests := []struct {
- caption string
- specSrc string
- src string
- actLog []string
- }{
- {
- caption: "when an input contains no syntax error, the driver calls `Shift`, `Reduce`, and `Accept`.",
- specSrc: specSrcWithErrorProd,
- src: `a b c; d e f;`,
- actLog: []string{
- "shift/char",
- "shift/char",
- "shift/char",
- "reduce/elem",
- "shift/semicolon",
- "reduce/seq",
-
- "shift/char",
- "shift/char",
- "shift/char",
- "reduce/elem",
- "shift/semicolon",
- "reduce/seq",
-
- "accept",
- },
- },
- {
- caption: "when a grammar has `error` symbol, the driver calls `TrapAndShiftError`.",
- specSrc: specSrcWithErrorProd,
- src: `a; b !; c d !; e ! * *; h i j;`,
- actLog: []string{
- "shift/char",
- "trap/1/shift/error",
- "shift/semicolon",
- "reduce/seq/recovered",
-
- "shift/char",
- "trap/2/shift/error",
- "shift/semicolon",
- "reduce/seq/recovered",
-
- "shift/char",
- "shift/char",
- "trap/3/shift/error",
- "shift/semicolon",
- "reduce/seq/recovered",
-
- "shift/char",
- "trap/2/shift/error",
- "shift/star",
- "shift/star",
- // When the driver shifts three times, it recovers from an error.
- "shift/semicolon/recovered",
- "reduce/seq",
-
- "shift/char",
- "shift/char",
- "shift/char",
- "reduce/elem",
- "shift/semicolon",
- "reduce/seq",
-
- // Even if the input contains syntax errors, the driver calls `Accept` when the input is accepted
- // according to the error production.
- "accept",
- },
- },
- {
- caption: "when the input doesn't meet the error production, the driver calls `MissError`.",
- specSrc: specSrcWithErrorProd,
- src: `a !`,
- actLog: []string{
- "shift/char",
- "trap/1/shift/error",
-
- "miss",
- },
- },
- {
- caption: "when a syntax error isn't trapped, the driver calls `MissError`.",
- specSrc: specSrcWithoutErrorProd,
- src: `a !`,
- actLog: []string{
- "shift/char",
-
- "miss",
- },
- },
- }
- for _, tt := range tests {
- t.Run(tt.caption, func(t *testing.T) {
- ast, err := parser.Parse(strings.NewReader(tt.specSrc))
- if err != nil {
- t.Fatal(err)
- }
-
- b := grammar.GrammarBuilder{
- AST: ast,
- }
- gram, _, err := b.Build()
- if err != nil {
- t.Fatal(err)
- }
-
- toks, err := NewTokenStream(gram, strings.NewReader(tt.src))
- if err != nil {
- t.Fatal(err)
- }
-
- semAct := &testSemAct{
- gram: gram,
- }
- p, err := NewParser(toks, NewGrammar(gram), SemanticAction(semAct))
- if err != nil {
- t.Fatal(err)
- }
-
- err = p.Parse()
- if err != nil {
- t.Fatal(err)
- }
-
- if len(semAct.actLog) != len(tt.actLog) {
- t.Fatalf("unexpected action log; want: %+v, got: %+v", tt.actLog, semAct.actLog)
- }
-
- for i, e := range tt.actLog {
- if semAct.actLog[i] != e {
- t.Fatalf("unexpected action log; want: %+v, got: %+v", tt.actLog, semAct.actLog)
- }
- }
- })
- }
-}
diff --git a/driver/parser/spec.go b/driver/parser/spec.go
deleted file mode 100644
index b288f5f..0000000
--- a/driver/parser/spec.go
+++ /dev/null
@@ -1,73 +0,0 @@
-package parser
-
-import spec "spec/grammar"
-
-type grammarImpl struct {
- g *spec.CompiledGrammar
-}
-
-func NewGrammar(g *spec.CompiledGrammar) *grammarImpl {
- return &grammarImpl{
- g: g,
- }
-}
-
-func (g *grammarImpl) InitialState() int {
- return g.g.Syntactic.InitialState
-}
-
-func (g *grammarImpl) StartProduction() int {
- return g.g.Syntactic.StartProduction
-}
-
-func (g *grammarImpl) RecoverProduction(prod int) bool {
- return g.g.Syntactic.RecoverProductions[prod] != 0
-}
-
-func (g *grammarImpl) Action(state int, terminal int) int {
- return g.g.Syntactic.Action[state*g.g.Syntactic.TerminalCount+terminal]
-}
-
-func (g *grammarImpl) GoTo(state int, lhs int) int {
- return g.g.Syntactic.GoTo[state*g.g.Syntactic.NonTerminalCount+lhs]
-}
-
-func (g *grammarImpl) AlternativeSymbolCount(prod int) int {
- return g.g.Syntactic.AlternativeSymbolCounts[prod]
-}
-
-func (g *grammarImpl) TerminalCount() int {
- return g.g.Syntactic.TerminalCount
-}
-
-func (g *grammarImpl) SkipTerminal(terminal int) bool {
- return g.g.Syntactic.TerminalSkip[terminal] == 1
-}
-
-func (g *grammarImpl) ErrorTrapperState(state int) bool {
- return g.g.Syntactic.ErrorTrapperStates[state] != 0
-}
-
-func (g *grammarImpl) NonTerminal(nonTerminal int) string {
- return g.g.Syntactic.NonTerminals[nonTerminal]
-}
-
-func (g *grammarImpl) LHS(prod int) int {
- return g.g.Syntactic.LHSSymbols[prod]
-}
-
-func (g *grammarImpl) EOF() int {
- return g.g.Syntactic.EOFSymbol
-}
-
-func (g *grammarImpl) Error() int {
- return g.g.Syntactic.ErrorSymbol
-}
-
-func (g *grammarImpl) Terminal(terminal int) string {
- return g.g.Syntactic.Terminals[terminal]
-}
-
-func (g *grammarImpl) ASTAction(prod int) []int {
- return g.g.ASTAction.Entries[prod]
-}
diff --git a/driver/parser/syntax_error_test.go b/driver/parser/syntax_error_test.go
deleted file mode 100644
index c508be6..0000000
--- a/driver/parser/syntax_error_test.go
+++ /dev/null
@@ -1,306 +0,0 @@
-package parser
-
-import (
- "fmt"
- "sort"
- "strings"
- "testing"
-
- "grammar"
- "spec/grammar/parser"
-)
-
-func TestParserWithSyntaxErrors(t *testing.T) {
- tests := []struct {
- caption string
- specSrc string
- src string
- synErrCount int
- }{
- {
- caption: "the parser can report a syntax error",
- specSrc: `
-#name test;
-
-s
- : foo
- ;
-
-foo
- : 'foo';
-`,
- src: `bar`,
- synErrCount: 1,
- },
- {
- caption: "when the parser reduced a production having the reduce directive, the parser will recover from an error state",
- specSrc: `
-#name test;
-
-seq
- : seq elem semi_colon
- | elem semi_colon
- | error semi_colon #recover
- ;
-elem
- : a b c
- ;
-
-ws #skip
- : "[\u{0009}\u{0020}]+";
-semi_colon
- : ';';
-a
- : 'a';
-b
- : 'b';
-c
- : 'c';
-`,
- src: `!; a!; ab!;`,
- synErrCount: 3,
- },
- {
- caption: "After the parser shifts the error symbol, symbols are ignored until a symbol the parser can perform shift appears",
- specSrc: `
-#name test;
-
-seq
- : seq elem semi_colon
- | elem semi_colon
- | error semi_colon #recover
- ;
-elem
- : a b c
- ;
-
-ws #skip
- : "[\u{0009}\u{0020}]+";
-semi_colon
- : ';';
-a
- : 'a';
-b
- : 'b';
-c
- : 'c';
-`,
- // After the parser trasits to the error state reading the first invalid symbol ('!'),
- // the second and third invalid symbols ('!') are ignored.
- src: `! ! !; a!; ab!;`,
- synErrCount: 3,
- },
- {
- caption: "when the parser performs shift three times, the parser recovers from the error state",
- specSrc: `
-#name test;
-
-seq
- : seq elem semi_colon
- | elem semi_colon
- | error star star semi_colon
- ;
-elem
- : a b c
- ;
-
-ws #skip
- : "[\u{0009}\u{0020}]+";
-semi_colon
- : ';';
-star
- : '*';
-a
- : 'a';
-b
- : 'b';
-c
- : 'c';
-`,
- src: `!**; a!**; ab!**; abc!`,
- synErrCount: 4,
- },
- }
- for i, tt := range tests {
- t.Run(fmt.Sprintf("#%v", i), func(t *testing.T) {
- ast, err := parser.Parse(strings.NewReader(tt.specSrc))
- if err != nil {
- t.Fatal(err)
- }
-
- b := grammar.GrammarBuilder{
- AST: ast,
- }
- gram, _, err := b.Build()
- if err != nil {
- t.Fatal(err)
- }
-
- toks, err := NewTokenStream(gram, strings.NewReader(tt.src))
- if err != nil {
- t.Fatal(err)
- }
-
- p, err := NewParser(toks, NewGrammar(gram))
- if err != nil {
- t.Fatal(err)
- }
-
- err = p.Parse()
- if err != nil {
- t.Fatal(err)
- }
-
- synErrs := p.SyntaxErrors()
- if len(synErrs) != tt.synErrCount {
- t.Fatalf("unexpected syntax error; want: %v error(s), got: %v error(s)", tt.synErrCount, len(synErrs))
- }
- })
- }
-}
-
-func TestParserWithSyntaxErrorAndExpectedLookahead(t *testing.T) {
- tests := []struct {
- caption string
- specSrc string
- src string
- cause string
- expected []string
- }{
- {
- caption: "the parser reports an expected lookahead symbol",
- specSrc: `
-#name test;
-
-s
- : foo
- ;
-
-foo
- : 'foo';
-`,
- src: `bar`,
- cause: `bar`,
- expected: []string{
- "foo",
- },
- },
- {
- caption: "the parser reports expected lookahead symbols",
- specSrc: `
-#name test;
-
-s
- : foo
- | bar
- ;
-
-foo
- : 'foo';
-bar
- : 'bar';
-`,
- src: `baz`,
- cause: `baz`,
- expected: []string{
- "foo",
- "bar",
- },
- },
- {
- caption: "the parser may report the EOF as an expected lookahead symbol",
- specSrc: `
-#name test;
-
-s
- : foo
- ;
-
-foo
- : 'foo';
-`,
- src: `foobar`,
- cause: `bar`,
- expected: []string{
- "<eof>",
- },
- },
- {
- caption: "the parser may report the EOF and others as expected lookahead symbols",
- specSrc: `
-#name test;
-
-s
- : foo
- |
- ;
-
-foo
- : 'foo';
-`,
- src: `bar`,
- cause: `bar`,
- expected: []string{
- "foo",
- "<eof>",
- },
- },
- }
- for i, tt := range tests {
- t.Run(fmt.Sprintf("#%v", i), func(t *testing.T) {
- ast, err := parser.Parse(strings.NewReader(tt.specSrc))
- if err != nil {
- t.Fatal(err)
- }
-
- b := grammar.GrammarBuilder{
- AST: ast,
- }
- gram, _, err := b.Build()
- if err != nil {
- t.Fatal(err)
- }
-
- toks, err := NewTokenStream(gram, strings.NewReader(tt.src))
- if err != nil {
- t.Fatal(err)
- }
-
- p, err := NewParser(toks, NewGrammar(gram))
- if err != nil {
- t.Fatal(err)
- }
-
- err = p.Parse()
- if err != nil {
- t.Fatal(err)
- }
-
- synErrs := p.SyntaxErrors()
- if synErrs == nil {
- t.Fatalf("expected one syntax error, but it didn't occur")
- }
- if len(synErrs) != 1 {
- t.Fatalf("too many syntax errors: %v errors", len(synErrs))
- }
- synErr := synErrs[0]
- if string(synErr.Token.Lexeme()) != tt.cause {
- t.Fatalf("unexpected lexeme: want: %v, got: %v", tt.cause, string(synErr.Token.Lexeme()))
- }
- if len(synErr.ExpectedTerminals) != len(tt.expected) {
- t.Fatalf("unexpected lookahead symbols: want: %v, got: %v", tt.expected, synErr.ExpectedTerminals)
- }
- sort.Slice(tt.expected, func(i, j int) bool {
- return tt.expected[i] < tt.expected[j]
- })
- sort.Slice(synErr.ExpectedTerminals, func(i, j int) bool {
- return synErr.ExpectedTerminals[i] < synErr.ExpectedTerminals[j]
- })
- for i, e := range tt.expected {
- if synErr.ExpectedTerminals[i] != e {
- t.Errorf("unexpected lookahead symbol: want: %v, got: %v", e, synErr.ExpectedTerminals[i])
- }
- }
- })
- }
-}
diff --git a/driver/parser/template.go b/driver/parser/template.go
deleted file mode 100644
index 3e25193..0000000
--- a/driver/parser/template.go
+++ /dev/null
@@ -1,535 +0,0 @@
-package parser
-
-import (
- "bytes"
- _ "embed"
- "fmt"
- "go/ast"
- "go/format"
- "go/parser"
- "go/token"
- goToken "go/token"
- "strconv"
- "strings"
- "text/template"
-
- spec "spec/grammar"
-)
-
-// go:embed parser.go
-var parserCoreSrc string
-
-// go:embed semantic_action.go
-var semActSrc string
-
-func GenParser(cgram *spec.CompiledGrammar, pkgName string) ([]byte, error) {
- var parserSrc string
- {
- fset := goToken.NewFileSet()
- f, err := parser.ParseFile(fset, "parser.go", parserCoreSrc, parser.ParseComments)
- if err != nil {
- return nil, err
- }
-
- var b strings.Builder
- err = format.Node(&b, fset, f)
- if err != nil {
- return nil, err
- }
-
- parserSrc = b.String()
- }
-
- var grammarSrc string
- {
- t, err := template.New("").Funcs(genGrammarTemplateFuncs(cgram)).Parse(grammarSrcTmplate)
- if err != nil {
- return nil, err
- }
-
- var b strings.Builder
- err = t.Execute(&b, map[string]interface{}{
- "initialState": cgram.Syntactic.InitialState,
- "startProduction": cgram.Syntactic.StartProduction,
- "terminalCount": cgram.Syntactic.TerminalCount,
- "nonTerminalCount": cgram.Syntactic.NonTerminalCount,
- "eofSymbol": cgram.Syntactic.EOFSymbol,
- "errorSymbol": cgram.Syntactic.ErrorSymbol,
- })
- if err != nil {
- return nil, err
- }
-
- grammarSrc = b.String()
- }
-
- var lexerSrc string
- {
- t, err := template.New("").Funcs(genLexerTemplateFuncs(cgram)).Parse(lexerSrcTmplate)
- if err != nil {
- return nil, err
- }
-
- var b strings.Builder
- err = t.Execute(&b, nil)
- if err != nil {
- return nil, err
- }
-
- lexerSrc = b.String()
- }
-
- var src string
- {
- tmpl := `// Code generated by vartan-go. DO NOT EDIT.
-{{ .parserSrc }}
-
-{{ .grammarSrc }}
-
-{{ .lexerSrc }}
-`
- t, err := template.New("").Parse(tmpl)
- if err != nil {
- return nil, err
- }
-
- var b strings.Builder
- err = t.Execute(&b, map[string]string{
- "parserSrc": parserSrc,
- "grammarSrc": grammarSrc,
- "lexerSrc": lexerSrc,
- })
- if err != nil {
- return nil, err
- }
-
- src = b.String()
- }
-
- fset := goToken.NewFileSet()
- f, err := parser.ParseFile(fset, "", src, parser.ParseComments)
- if err != nil {
- return nil, err
- }
-
- f.Name = ast.NewIdent(pkgName)
-
- // Complete an import statement.
- for _, d := range f.Decls {
- gd, ok := d.(*ast.GenDecl)
- if !ok || gd.Tok != token.IMPORT {
- continue
- }
- gd.Specs = append(gd.Specs, &ast.ImportSpec{
- Path: &ast.BasicLit{
- Value: `"io"`,
- },
- })
- break
- }
-
- var b bytes.Buffer
- err = format.Node(&b, fset, f)
- if err != nil {
- return nil, err
- }
-
- return b.Bytes(), nil
-}
-
-const grammarSrcTmplate = `
-type grammarImpl struct {
- recoverProductions []int
- action []int
- goTo []int
- alternativeSymbolCounts []int
- errorTrapperStates []int
- nonTerminals []string
- lhsSymbols []int
- terminals []string
- terminalSkip []int
- astActions [][]int
-}
-
-func NewGrammar() *grammarImpl {
- return &grammarImpl{
- recoverProductions: {{ genRecoverProductions }},
- action: {{ genAction }},
- goTo: {{ genGoTo }},
- alternativeSymbolCounts: {{ genAlternativeSymbolCounts }},
- errorTrapperStates: {{ genErrorTrapperStates }},
- nonTerminals: {{ genNonTerminals }},
- lhsSymbols: {{ genLHSSymbols }},
- terminals: {{ genTerminals }},
- terminalSkip: {{ genTerminalSkip }},
- astActions: {{ genASTActions }},
- }
-}
-
-func (g *grammarImpl) InitialState() int {
- return {{ .initialState }}
-}
-
-func (g *grammarImpl) StartProduction() int {
- return {{ .startProduction }}
-}
-
-func (g *grammarImpl) RecoverProduction(prod int) bool {
- return g.recoverProductions[prod] != 0
-}
-
-func (g *grammarImpl) Action(state int, terminal int) int {
- return g.action[state*{{ .terminalCount }}+terminal]
-}
-
-func (g *grammarImpl) GoTo(state int, lhs int) int {
- return g.goTo[state*{{ .nonTerminalCount }}+lhs]
-}
-
-func (g *grammarImpl) AlternativeSymbolCount(prod int) int {
- return g.alternativeSymbolCounts[prod]
-}
-
-func (g *grammarImpl) TerminalCount() int {
- return {{ .terminalCount }}
-}
-
-func (g *grammarImpl) SkipTerminal(terminal int) bool {
- return g.terminalSkip[terminal] == 1
-}
-
-func (g *grammarImpl) ErrorTrapperState(state int) bool {
- return g.errorTrapperStates[state] != 0
-}
-
-func (g *grammarImpl) NonTerminal(nonTerminal int) string {
- return g.nonTerminals[nonTerminal]
-}
-
-func (g *grammarImpl) LHS(prod int) int {
- return g.lhsSymbols[prod]
-}
-
-func (g *grammarImpl) EOF() int {
- return {{ .eofSymbol }}
-}
-
-func (g *grammarImpl) Error() int {
- return {{ .errorSymbol }}
-}
-
-func (g *grammarImpl) Terminal(terminal int) string {
- return g.terminals[terminal]
-}
-
-func (g *grammarImpl) ASTAction(prod int) []int {
- return g.astActions[prod]
-}
-`
-
-func genGrammarTemplateFuncs(cgram *spec.CompiledGrammar) template.FuncMap {
- return template.FuncMap{
- "genRecoverProductions": func() string {
- var b strings.Builder
- fmt.Fprintf(&b, "[]int{\n")
- c := 1
- for _, v := range cgram.Syntactic.RecoverProductions {
- fmt.Fprintf(&b, "%v, ", v)
- if c == 20 {
- fmt.Fprintf(&b, "\n")
- c = 1
- } else {
- c++
- }
- }
- if c > 1 {
- fmt.Fprintf(&b, "\n")
- }
- fmt.Fprintf(&b, "}")
- return b.String()
- },
- "genAction": func() string {
- var b strings.Builder
- fmt.Fprintf(&b, "[]int{\n")
- c := 1
- for _, v := range cgram.Syntactic.Action {
- fmt.Fprintf(&b, "%v, ", v)
- if c == 20 {
- fmt.Fprintf(&b, "\n")
- c = 1
- } else {
- c++
- }
- }
- if c > 1 {
- fmt.Fprintf(&b, "\n")
- }
- fmt.Fprintf(&b, "}")
- return b.String()
- },
- "genGoTo": func() string {
- var b strings.Builder
- fmt.Fprintf(&b, "[]int{\n")
- c := 1
- for _, v := range cgram.Syntactic.GoTo {
- fmt.Fprintf(&b, "%v, ", v)
- if c == 20 {
- fmt.Fprintf(&b, "\n")
- c = 1
- } else {
- c++
- }
- }
- if c > 1 {
- fmt.Fprintf(&b, "\n")
- }
- fmt.Fprintf(&b, "}")
- return b.String()
- },
- "genAlternativeSymbolCounts": func() string {
- var b strings.Builder
- fmt.Fprintf(&b, "[]int{\n")
- c := 1
- for _, v := range cgram.Syntactic.AlternativeSymbolCounts {
- fmt.Fprintf(&b, "%v, ", v)
- if c == 20 {
- fmt.Fprintf(&b, "\n")
- c = 1
- } else {
- c++
- }
- }
- if c > 1 {
- fmt.Fprintf(&b, "\n")
- }
- fmt.Fprintf(&b, "}")
- return b.String()
- },
- "genErrorTrapperStates": func() string {
- var b strings.Builder
- fmt.Fprintf(&b, "[]int{\n")
- c := 1
- for _, v := range cgram.Syntactic.ErrorTrapperStates {
- fmt.Fprintf(&b, "%v, ", v)
- if c == 20 {
- fmt.Fprintf(&b, "\n")
- c = 1
- } else {
- c++
- }
- }
- if c > 1 {
- fmt.Fprintf(&b, "\n")
- }
- fmt.Fprintf(&b, "}")
- return b.String()
- },
- "genNonTerminals": func() string {
- var b strings.Builder
- fmt.Fprintf(&b, "[]string{\n")
- for _, v := range cgram.Syntactic.NonTerminals {
- fmt.Fprintf(&b, "%v,\n", strconv.Quote(v))
- }
- fmt.Fprintf(&b, "}")
- return b.String()
- },
- "genLHSSymbols": func() string {
- var b strings.Builder
- fmt.Fprintf(&b, "[]int{\n")
- c := 1
- for _, v := range cgram.Syntactic.LHSSymbols {
- fmt.Fprintf(&b, "%v, ", v)
- if c == 20 {
- fmt.Fprintf(&b, "\n")
- c = 1
- } else {
- c++
- }
- }
- if c > 1 {
- fmt.Fprintf(&b, "\n")
- }
- fmt.Fprintf(&b, "}")
- return b.String()
- },
- "genTerminals": func() string {
- var b strings.Builder
- fmt.Fprintf(&b, "[]string{\n")
- for _, v := range cgram.Syntactic.Terminals {
- fmt.Fprintf(&b, "%v,\n", strconv.Quote(v))
- }
- fmt.Fprintf(&b, "}")
- return b.String()
- },
- "genTerminalSkip": func() string {
- var b strings.Builder
- fmt.Fprintf(&b, "[]int{\n")
- c := 1
- for _, v := range cgram.Syntactic.TerminalSkip {
- fmt.Fprintf(&b, "%v, ", v)
- if c == 20 {
- fmt.Fprintf(&b, "\n")
- c = 1
- } else {
- c++
- }
- }
- if c > 1 {
- fmt.Fprintf(&b, "\n")
- }
- fmt.Fprintf(&b, "}")
- return b.String()
- },
- "genASTActions": func() string {
- var b strings.Builder
- fmt.Fprintf(&b, "[][]int{\n")
- for _, entries := range cgram.ASTAction.Entries {
- if len(entries) == 0 {
- fmt.Fprintf(&b, "nil,\n")
- continue
- }
-
- fmt.Fprintf(&b, "{\n")
- c := 1
- for _, v := range entries {
- fmt.Fprintf(&b, "%v, ", v)
- if c == 20 {
- fmt.Fprintf(&b, "\n")
- c = 1
- } else {
- c++
- }
- }
- if c > 1 {
- fmt.Fprintf(&b, "\n")
- }
- fmt.Fprintf(&b, "},\n")
- }
- fmt.Fprintf(&b, "}")
- return b.String()
- },
- }
-}
-
-const lexerSrcTmplate = `
-type vToken struct {
- terminalID int
- tok *Token
-}
-
-func (t *vToken) TerminalID() int {
- return t.terminalID
-}
-
-func (t *vToken) Lexeme() []byte {
- return t.tok.Lexeme
-}
-
-func (t *vToken) EOF() bool {
- return t.tok.EOF
-}
-
-func (t *vToken) Invalid() bool {
- return t.tok.Invalid
-}
-
-func (t *vToken) BytePosition() (int, int) {
- return t.tok.BytePos, t.tok.ByteLen
-}
-
-func (t *vToken) Position() (int, int) {
- return t.tok.Row, t.tok.Col
-}
-
-var kindToTerminal = {{ genKindToTerminal }}
-
-type tokenStream struct {
- lex *Lexer
- kindToTerminal []int
-}
-
-func NewTokenStream(src io.Reader) (*tokenStream, error) {
- lex, err := NewLexer(NewLexSpec(), src)
- if err != nil {
- return nil, err
- }
-
- return &tokenStream{
- lex: lex,
- }, nil
-}
-
-func (t *tokenStream) Next() (VToken, error) {
- tok, err := t.lex.Next()
- if err != nil {
- return nil, err
- }
- return &vToken{
- terminalID: kindToTerminal[tok.KindID],
- tok: tok,
- }, nil
-}
-`
-
-func genLexerTemplateFuncs(cgram *spec.CompiledGrammar) template.FuncMap {
- return template.FuncMap{
- "genKindToTerminal": func() string {
- var b strings.Builder
- fmt.Fprintf(&b, "[]int{\n")
- c := 1
- for _, v := range cgram.Syntactic.KindToTerminal {
- fmt.Fprintf(&b, "%v, ", v)
- if c == 20 {
- fmt.Fprintf(&b, "\n")
- c = 1
- } else {
- c++
- }
- }
- if c > 1 {
- fmt.Fprintf(&b, "\n")
- }
- fmt.Fprintf(&b, "}")
- return b.String()
- },
- }
-}
-
-func GenSemanticAction(pkgName string) ([]byte, error) {
- var src string
- {
- tmpl := `// Code generated by vartan-go. DO NOT EDIT.
-{{ .semActSrc }}
-`
- t, err := template.New("").Parse(tmpl)
- if err != nil {
- return nil, err
- }
-
- var b strings.Builder
- err = t.Execute(&b, map[string]string{
- "semActSrc": semActSrc,
- })
- if err != nil {
- return nil, err
- }
-
- src = b.String()
- }
-
- fset := goToken.NewFileSet()
- f, err := parser.ParseFile(fset, "", src, parser.ParseComments)
- if err != nil {
- return nil, err
- }
-
- f.Name = ast.NewIdent(pkgName)
-
- var b bytes.Buffer
- err = format.Node(&b, fset, f)
- if err != nil {
- return nil, err
- }
-
- return b.Bytes(), nil
-}
diff --git a/driver/parser/token_stream.go b/driver/parser/token_stream.go
deleted file mode 100644
index b15e8bf..0000000
--- a/driver/parser/token_stream.go
+++ /dev/null
@@ -1,65 +0,0 @@
-package parser
-
-import (
- "io"
-
- "driver/lexer"
- spec "spec/grammar"
-)
-
-type vToken struct {
- terminalID int
- tok *lexer.Token
-}
-
-func (t *vToken) TerminalID() int {
- return t.terminalID
-}
-
-func (t *vToken) Lexeme() []byte {
- return t.tok.Lexeme
-}
-
-func (t *vToken) EOF() bool {
- return t.tok.EOF
-}
-
-func (t *vToken) Invalid() bool {
- return t.tok.Invalid
-}
-
-func (t *vToken) BytePosition() (int, int) {
- return t.tok.BytePos, t.tok.ByteLen
-}
-
-func (t *vToken) Position() (int, int) {
- return t.tok.Row, t.tok.Col
-}
-
-type tokenStream struct {
- lex *lexer.Lexer
- kindToTerminal []int
-}
-
-func NewTokenStream(g *spec.CompiledGrammar, src io.Reader) (TokenStream, error) {
- lex, err := lexer.NewLexer(lexer.NewLexSpec(g.Lexical), src)
- if err != nil {
- return nil, err
- }
-
- return &tokenStream{
- lex: lex,
- kindToTerminal: g.Syntactic.KindToTerminal,
- }, nil
-}
-
-func (l *tokenStream) Next() (VToken, error) {
- tok, err := l.lex.Next()
- if err != nil {
- return nil, err
- }
- return &vToken{
- terminalID: l.kindToTerminal[tok.KindID],
- tok: tok,
- }, nil
-}
generated by cgit v1.2.3 (git 2.49.0) at 2025-07-13 17:23:22 +0000