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Diffstat (limited to 'grammar/grammar.go')
-rw-r--r--grammar/grammar.go266
1 files changed, 155 insertions, 111 deletions
diff --git a/grammar/grammar.go b/grammar/grammar.go
index da1c77c..a5d6cb7 100644
--- a/grammar/grammar.go
+++ b/grammar/grammar.go
@@ -150,7 +150,7 @@ func (b *GrammarBuilder) Build() (*Grammar, error) {
return nil, b.errs
}
- pa, err := b.genPrecAndAssoc(symTabAndLexSpec.symTab, prodsAndActs.prods, prodsAndActs.prodPrecs, prodsAndActs.prodPrecPoss)
+ pa, err := b.genPrecAndAssoc(symTabAndLexSpec.symTab, prodsAndActs)
if err != nil {
return nil, err
}
@@ -597,12 +597,13 @@ func genLexEntry(prod *spec.ProductionNode) (*mlspec.LexEntry, bool, string, *ve
}
type productionsAndActions struct {
- prods *productionSet
- augStartSym symbol
- astActs map[productionID][]*astActionEntry
- prodPrecs map[productionID]symbol
- prodPrecPoss map[productionID]*spec.Position
- recoverProds map[productionID]struct{}
+ prods *productionSet
+ augStartSym symbol
+ astActs map[productionID][]*astActionEntry
+ prodPrecsTerm map[productionID]symbol
+ prodPrecsOrdSym map[productionID]string
+ prodPrecPoss map[productionID]*spec.Position
+ recoverProds map[productionID]struct{}
}
func (b *GrammarBuilder) genProductionsAndActions(root *spec.RootNode, symTabAndLexSpec *symbolTableAndLexSpec) (*productionsAndActions, error) {
@@ -620,7 +621,8 @@ func (b *GrammarBuilder) genProductionsAndActions(root *spec.RootNode, symTabAnd
prods := newProductionSet()
var augStartSym symbol
astActs := map[productionID][]*astActionEntry{}
- prodPrecs := map[productionID]symbol{}
+ prodPrecsTerm := map[productionID]symbol{}
+ prodPrecsOrdSym := map[productionID]string{}
prodPrecPoss := map[productionID]*spec.Position{}
recoverProds := map[productionID]struct{}{}
@@ -918,36 +920,42 @@ func (b *GrammarBuilder) genProductionsAndActions(root *spec.RootNode, symTabAnd
}
astActs[p.id] = astAct
case "prec":
- if len(dir.Parameters) != 1 || dir.Parameters[0].ID == "" {
+ if len(dir.Parameters) != 1 || (dir.Parameters[0].ID == "" && dir.Parameters[0].OrderedSymbol == "") {
b.errs = append(b.errs, &verr.SpecError{
Cause: semErrDirInvalidParam,
- Detail: "'prec' directive needs an ID parameter",
+ Detail: "'prec' directive needs just one ID parameter or ordered symbol",
Row: dir.Pos.Row,
Col: dir.Pos.Col,
})
continue LOOP_RHS
}
- sym, ok := symTab.toSymbol(dir.Parameters[0].ID)
- if !ok {
- b.errs = append(b.errs, &verr.SpecError{
- Cause: semErrDirInvalidParam,
- Detail: fmt.Sprintf("unknown terminal symbol: %v", dir.Parameters[0].ID),
- Row: dir.Pos.Row,
- Col: dir.Pos.Col,
- })
- continue LOOP_RHS
- }
- if !sym.isTerminal() {
- b.errs = append(b.errs, &verr.SpecError{
- Cause: semErrDirInvalidParam,
- Detail: fmt.Sprintf("the symbol must be a terminal: %v", dir.Parameters[0].ID),
- Row: dir.Pos.Row,
- Col: dir.Pos.Col,
- })
- continue LOOP_RHS
+ switch {
+ case dir.Parameters[0].ID != "":
+ sym, ok := symTab.toSymbol(dir.Parameters[0].ID)
+ if !ok {
+ b.errs = append(b.errs, &verr.SpecError{
+ Cause: semErrDirInvalidParam,
+ Detail: fmt.Sprintf("unknown terminal symbol: %v", dir.Parameters[0].ID),
+ Row: dir.Pos.Row,
+ Col: dir.Pos.Col,
+ })
+ continue LOOP_RHS
+ }
+ if !sym.isTerminal() {
+ b.errs = append(b.errs, &verr.SpecError{
+ Cause: semErrDirInvalidParam,
+ Detail: fmt.Sprintf("the symbol must be a terminal: %v", dir.Parameters[0].ID),
+ Row: dir.Pos.Row,
+ Col: dir.Pos.Col,
+ })
+ continue LOOP_RHS
+ }
+ prodPrecsTerm[p.id] = sym
+ prodPrecPoss[p.id] = &dir.Parameters[0].Pos
+ case dir.Parameters[0].OrderedSymbol != "":
+ prodPrecsOrdSym[p.id] = dir.Parameters[0].OrderedSymbol
+ prodPrecPoss[p.id] = &dir.Parameters[0].Pos
}
- prodPrecs[p.id] = sym
- prodPrecPoss[p.id] = &dir.Parameters[0].Pos
case "recover":
if len(dir.Parameters) > 0 {
b.errs = append(b.errs, &verr.SpecError{
@@ -973,18 +981,20 @@ func (b *GrammarBuilder) genProductionsAndActions(root *spec.RootNode, symTabAnd
}
return &productionsAndActions{
- prods: prods,
- augStartSym: augStartSym,
- astActs: astActs,
- prodPrecs: prodPrecs,
- prodPrecPoss: prodPrecPoss,
- recoverProds: recoverProds,
+ prods: prods,
+ augStartSym: augStartSym,
+ astActs: astActs,
+ prodPrecsTerm: prodPrecsTerm,
+ prodPrecsOrdSym: prodPrecsOrdSym,
+ prodPrecPoss: prodPrecPoss,
+ recoverProds: recoverProds,
}, nil
}
-func (b *GrammarBuilder) genPrecAndAssoc(symTab *symbolTable, prods *productionSet, prodPrecs map[productionID]symbol, prodPrecPoss map[productionID]*spec.Position) (*precAndAssoc, error) {
+func (b *GrammarBuilder) genPrecAndAssoc(symTab *symbolTable, prodsAndActs *productionsAndActions) (*precAndAssoc, error) {
termPrec := map[symbolNum]int{}
termAssoc := map[symbolNum]assocType{}
+ ordSymPrec := map[string]int{}
{
var precGroup []*spec.DirectiveNode
for _, dir := range b.AST.Directives {
@@ -1004,9 +1014,10 @@ func (b *GrammarBuilder) genPrecAndAssoc(symTab *symbolTable, prods *productionS
if dir.Name != "name" && dir.Name != "prec" {
b.errs = append(b.errs, &verr.SpecError{
- Cause: semErrDirInvalidName,
- Row: dir.Pos.Row,
- Col: dir.Pos.Col,
+ Cause: semErrDirInvalidName,
+ Detail: dir.Name,
+ Row: dir.Pos.Row,
+ Col: dir.Pos.Col,
})
continue
}
@@ -1024,9 +1035,10 @@ func (b *GrammarBuilder) genPrecAndAssoc(symTab *symbolTable, prods *productionS
assocTy = assocTypeNil
default:
b.errs = append(b.errs, &verr.SpecError{
- Cause: semErrDirInvalidName,
- Row: dir.Pos.Row,
- Col: dir.Pos.Col,
+ Cause: semErrDirInvalidName,
+ Detail: dir.Name,
+ Row: dir.Pos.Row,
+ Col: dir.Pos.Col,
})
return nil, nil
}
@@ -1042,63 +1054,85 @@ func (b *GrammarBuilder) genPrecAndAssoc(symTab *symbolTable, prods *productionS
}
ASSOC_PARAM_LOOP:
for _, p := range dir.Parameters {
- if p.ID == "" {
- b.errs = append(b.errs, &verr.SpecError{
- Cause: semErrDirInvalidParam,
- Detail: "a parameter must be an ID",
- Row: p.Pos.Row,
- Col: p.Pos.Col,
- })
- return nil, nil
- }
-
- sym, ok := symTab.toSymbol(p.ID)
- if !ok {
- b.errs = append(b.errs, &verr.SpecError{
- Cause: semErrDirInvalidParam,
- Detail: fmt.Sprintf("'%v' is undefined", p.ID),
- Row: p.Pos.Row,
- Col: p.Pos.Col,
- })
- return nil, nil
- }
- if !sym.isTerminal() {
- b.errs = append(b.errs, &verr.SpecError{
- Cause: semErrDirInvalidParam,
- Detail: fmt.Sprintf("associativity can take only terminal symbol ('%v' is a non-terminal)", p.ID),
- Row: p.Pos.Row,
- Col: p.Pos.Col,
- })
- return nil, nil
- }
- if prec, alreadySet := termPrec[sym.num()]; alreadySet {
- if prec == precN {
- b.errs = append(b.errs, &verr.SpecError{
- Cause: semErrDuplicateAssoc,
- Detail: fmt.Sprintf("'%v' already has the same associativity and precedence", p.ID),
- Row: p.Pos.Row,
- Col: p.Pos.Col,
- })
- } else if assoc := termAssoc[sym.num()]; assoc == assocTy {
+ switch {
+ case p.ID != "":
+ sym, ok := symTab.toSymbol(p.ID)
+ if !ok {
b.errs = append(b.errs, &verr.SpecError{
- Cause: semErrDuplicateAssoc,
- Detail: fmt.Sprintf("'%v' already has different precedence", p.ID),
+ Cause: semErrDirInvalidParam,
+ Detail: fmt.Sprintf("'%v' is undefined", p.ID),
Row: p.Pos.Row,
Col: p.Pos.Col,
})
- } else {
+ return nil, nil
+ }
+ if !sym.isTerminal() {
b.errs = append(b.errs, &verr.SpecError{
- Cause: semErrDuplicateAssoc,
- Detail: fmt.Sprintf("'%v' already has different associativity and precedence", p.ID),
+ Cause: semErrDirInvalidParam,
+ Detail: fmt.Sprintf("associativity can take only terminal symbol ('%v' is a non-terminal)", p.ID),
Row: p.Pos.Row,
Col: p.Pos.Col,
})
+ return nil, nil
+ }
+ if prec, alreadySet := termPrec[sym.num()]; alreadySet {
+ if prec == precN {
+ b.errs = append(b.errs, &verr.SpecError{
+ Cause: semErrDuplicateAssoc,
+ Detail: fmt.Sprintf("'%v' already has the same associativity and precedence", p.ID),
+ Row: p.Pos.Row,
+ Col: p.Pos.Col,
+ })
+ } else if assoc := termAssoc[sym.num()]; assoc == assocTy {
+ b.errs = append(b.errs, &verr.SpecError{
+ Cause: semErrDuplicateAssoc,
+ Detail: fmt.Sprintf("'%v' already has different precedence", p.ID),
+ Row: p.Pos.Row,
+ Col: p.Pos.Col,
+ })
+ } else {
+ b.errs = append(b.errs, &verr.SpecError{
+ Cause: semErrDuplicateAssoc,
+ Detail: fmt.Sprintf("'%v' already has different associativity and precedence", p.ID),
+ Row: p.Pos.Row,
+ Col: p.Pos.Col,
+ })
+ }
+ break ASSOC_PARAM_LOOP
+ }
+
+ termPrec[sym.num()] = precN
+ termAssoc[sym.num()] = assocTy
+ case p.OrderedSymbol != "":
+ if prec, alreadySet := ordSymPrec[p.OrderedSymbol]; alreadySet {
+ if prec == precN {
+ b.errs = append(b.errs, &verr.SpecError{
+ Cause: semErrDuplicateAssoc,
+ Detail: fmt.Sprintf("'$%v' already has the same precedence", p.OrderedSymbol),
+ Row: p.Pos.Row,
+ Col: p.Pos.Col,
+ })
+ } else {
+ b.errs = append(b.errs, &verr.SpecError{
+ Cause: semErrDuplicateAssoc,
+ Detail: fmt.Sprintf("'$%v' already has different precedence", p.OrderedSymbol),
+ Row: p.Pos.Row,
+ Col: p.Pos.Col,
+ })
+ }
+ break ASSOC_PARAM_LOOP
}
- break ASSOC_PARAM_LOOP
- }
- termPrec[sym.num()] = precN
- termAssoc[sym.num()] = assocTy
+ ordSymPrec[p.OrderedSymbol] = precN
+ default:
+ b.errs = append(b.errs, &verr.SpecError{
+ Cause: semErrDirInvalidParam,
+ Detail: "a parameter must be an ID or an ordered symbol",
+ Row: p.Pos.Row,
+ Col: p.Pos.Col,
+ })
+ return nil, nil
+ }
}
precN++
@@ -1110,36 +1144,46 @@ func (b *GrammarBuilder) genPrecAndAssoc(symTab *symbolTable, prods *productionS
prodPrec := map[productionNum]int{}
prodAssoc := map[productionNum]assocType{}
- for _, prod := range prods.getAllProductions() {
- mostrightTerm := symbolNil
- for _, sym := range prod.rhs {
- if !sym.isTerminal() {
- continue
- }
- mostrightTerm = sym
- }
- if !mostrightTerm.isNil() {
- if prec, ok := termPrec[mostrightTerm.num()]; ok {
- prodPrec[prod.num] = prec
- }
- if assoc, ok := termAssoc[mostrightTerm.num()]; ok {
- prodAssoc[prod.num] = assoc
- }
- }
-
- // #prec directive changes only precedence, not associativity.
- if term, ok := prodPrecs[prod.id]; ok {
+ for _, prod := range prodsAndActs.prods.getAllProductions() {
+ // A #prec directive changes only precedence, not associativity.
+ if term, ok := prodsAndActs.prodPrecsTerm[prod.id]; ok {
if prec, ok := termPrec[term.num()]; ok {
prodPrec[prod.num] = prec
+ prodAssoc[prod.num] = assocTypeNil
} else {
text, _ := symTab.toText(term)
b.errs = append(b.errs, &verr.SpecError{
Cause: semErrUndefinedPrec,
Detail: text,
- Row: prodPrecPoss[prod.id].Row,
- Col: prodPrecPoss[prod.id].Col,
+ Row: prodsAndActs.prodPrecPoss[prod.id].Row,
+ Col: prodsAndActs.prodPrecPoss[prod.id].Col,
})
}
+ } else if ordSym, ok := prodsAndActs.prodPrecsOrdSym[prod.id]; ok {
+ if prec, ok := ordSymPrec[ordSym]; ok {
+ prodPrec[prod.num] = prec
+ prodAssoc[prod.num] = assocTypeNil
+ } else {
+ b.errs = append(b.errs, &verr.SpecError{
+ Cause: semErrUndefinedOrdSym,
+ Detail: fmt.Sprintf("$%v", ordSym),
+ Row: prodsAndActs.prodPrecPoss[prod.id].Row,
+ Col: prodsAndActs.prodPrecPoss[prod.id].Col,
+ })
+ }
+ } else {
+ // A production inherits precedence and associativity from the right-most terminal symbol.
+ mostrightTerm := symbolNil
+ for _, sym := range prod.rhs {
+ if !sym.isTerminal() {
+ continue
+ }
+ mostrightTerm = sym
+ }
+ if !mostrightTerm.isNil() {
+ prodPrec[prod.num] = termPrec[mostrightTerm.num()]
+ prodAssoc[prod.num] = termAssoc[mostrightTerm.num()]
+ }
}
}
if len(b.errs) > 0 {
generated by cgit v1.2.3 (git 2.49.0) at 2025-07-13 15:59:05 +0000