*: fix the bug none use nonTerminal symbol

LALR/LALR.go

@@ -285,6 +285,20 @@ func ComputeLALR(g *grammar.Grammar) *LALR1 {
 		panic(err.Error())
 	} else {
 		// try to split the table and pack it
+		if utils.DebugPackTab {
+			fmt.Print("/*     ")
+			for _, sy := range lalr.G.Symbols {
+				fmt.Printf("%s\t", sy.Name)
+			}
+			fmt.Println("*/")
+			for index, row := range tab {
+				fmt.Printf("/* %d */ {", index)
+				for _, val := range row {
+					fmt.Printf("%d,\t", val)
+				}
+				fmt.Println("},")
+			}
+		}
 		if err := lalr.TrySplitTable(tab); err != nil {
 			fmt.Println(err.Error())
 		}
@@ -320,6 +334,7 @@ func (lalr *LALR1) TrySplitTable(tab [][]int) error {
 	actTab, goTab := lalr.SplitActionAndGotoTable(tab)
 	// try to pack the table
 	actdef := make([]int, len(actTab))
+
 	for i := range actTab {
 		actdef[i] = findMaxOccurence(actTab[i])
 		for j := range actTab[i] {
@@ -344,7 +359,21 @@ func (lalr *LALR1) TrySplitTable(tab [][]int) error {
 			actTab[j] = append(actTab[j], v)
 		}
 	}
+	if utils.DebugPackTab {
+		fmt.Println("==========Show Action Table===============")
+		for i, r := range actTab {
+			fmt.Printf("%d:%v\n", i, r)
+		}
+		fmt.Println("==========Show Action def===============")
+		for i, r := range actdef {
+			fmt.Printf("%d:%v\n", i, r)
+		}
+		fmt.Println("==========Show Goto Table===============")
+		for i, r := range gtdef {
+			fmt.Printf("%d:%v\n", i, r)
+		}
 
+	}
 	act, off, check := utils.PackTable(actTab)
 	if len(act)+len(off)+len(actdef)+len(gtdef) > len(tab)*len(tab[0]) {
 		return errors.New("the table is no need to pack")
@@ -353,6 +382,31 @@ func (lalr *LALR1) TrySplitTable(tab [][]int) error {
 	lalr.NeedPacked = true
 	lalr.ActionTable, lalr.OffsetTable, lalr.CheckTable = act, off, check
 	lalr.ActionDef, lalr.GoToDef = actdef, gtdef
+	if utils.DebugPackTab {
+		// Check the packed table is correct
+		res := 0
+		nTerminals := len(lalr.G.VtSet)
+		//nNonTerminals := len(lalr.G.VnSet) - 1 // skip the start symbol
+		for state, v := range tab {
+			for lookahead, val := range v {
+				if off[state]+lookahead < 0 {
+					res = lalr.GenErrorCode()
+				} else if off[state]+lookahead >= len(check) ||
+					check[off[state]+lookahead] != state {
+					if lookahead > nTerminals {
+						res = gtdef[lookahead-nTerminals-1]
+					} else {
+						res = actdef[state]
+					}
+				} else {
+					res = act[off[state]+lookahead]
+				}
+				if res != val {
+					panic(fmt.Sprintf("state:%d, lookahead:%d, the packed table is not correct", state, lookahead))
+				}
+			}
+		}
+	}
 	return nil
 }
 

LALR/Table.go

@@ -189,7 +189,7 @@ func (lalr *LALR1) GenTable() ([][]int, error) {
 
 func (lalr *LALR1) SplitActionAndGotoTable(tab [][]int) ([][]int, [][]int) {
 	nTerminals := len(lalr.G.VtSet)
-	nNonTerminals := len(lalr.G.VnSet)
+	nNonTerminals := len(lalr.G.VnSet) - 1 // skip the start symbol
 	fmt.Println("nTerminals", nTerminals, "nNonTerminals", nNonTerminals)
 	actionTable := [][]int{}
 	for i := 0; i < len(tab); i++ {
@@ -204,12 +204,11 @@ func (lalr *LALR1) SplitActionAndGotoTable(tab [][]int) ([][]int, [][]int) {
 	for i := 0; i < nNonTerminals; i++ {
 		row := make([]int, len(tab))
 		for j := 0; j < len(row); j++ {
-			row[j] = tab[j][nTerminals+i+1]
+			row[j] = tab[j][nTerminals+i+1] // 1 is the start symbol
 		}
 		gotoTable = append(gotoTable, row)
 	}
 	return actionTable, gotoTable
-
 }
 
 func getActionTypeName(act E_ActionType) string {

Parser/Vistor.go

@@ -309,6 +309,14 @@ func (w *Walker) BuildLALR1() *lalr.LALR1 {
 
 		}
 		// resolve symbol
+		// check the nonTerminal symbol is at left side
+		for _, sym := range g.Symbols {
+			if sym.IsNonTerminator {
+				if _, ok := g.VnSet[sym]; !ok {
+					panic(fmt.Sprintf("Check the nonterminal %s in left part of rules", sym.Name))
+				}
+			}
+		}
 		g.ResolveSymbols()
 		g.CalculateEpsilonClosure()
 		item_var := item.NewItem(0, 0)

Utils/flags.go

@@ -7,3 +7,4 @@ package utils
 var DebugFlags bool = false
 var PackFlags bool = true
 var HttpDebug bool = false
+var DebugPackTab bool = true