public LL1Table(InputGrammer inputGrammer) : base(inputGrammer)
{
generatedFirst = new GenerateFirst(inputGrammer);
GenerateFollow generatedFollow = new GenerateFollow(inputGrammer, generatedFirst);
if (!checkLeft())
{
throw new FailToGenerateLL1Exception("含有左递归或左公因子");
}
foreach (Production production in inputGrammer.userProductions)
{
List <string> firstSetOfRightPart = generatedFirst.getFirstFromPart(production.Values);
foreach (string token in firstSetOfRightPart.Where(i => (!inputGrammer.nonTerminalTokens.Contains(i) && i != PublicFunc.EPSILON)))
{
Item item = new Item(production.Key, token, production.ToString());
checkConflict(item);
table.Add(item);
}
if (firstSetOfRightPart.Contains(PublicFunc.EPSILON))
{
foreach (string token in generatedFollow[production.Key].Where(i => !inputGrammer.nonTerminalTokens.Contains(i)))
{
Item item = new Item(production.Key, token, production.ToString());
checkConflict(item);
table.Add(item);
}
}
}
}
public SLR1Table(DFAGraphBase DFAGraph, InputGrammer inputGrammer) : base(DFAGraph, inputGrammer)
{
GenerateFirst generatedFirst = new GenerateFirst(inputGrammer);
generatedFollow = new GenerateFollow(inputGrammer, generatedFirst);
generateLRTable();
}
public DFAGraphFromLR1(InputGrammer inputGrammer) : base(inputGrammer)
{
generatedFirst = new GenerateFirst(inputGrammer);
DFANodes.Add(new DFANode(closure(new List <ProductionInLR0> {
new ProductionInLR1(inputGrammer.userProductions[0], new List <string> {
PublicFunc.ENDSYMBOL
})
}), DFANodes.Count.ToString()));
generateDFAGraph <ProductionInLR1>(DFANodes);
}
private void button1_Click(object sender, EventArgs e)
{
try
{
InputGrammer inputGrammer = new InputGrammer(InputArea.Text);
GenerateFirst generatedFirst = new GenerateFirst(inputGrammer);
if (formFirstAndFollow == null)
{
formFirstAndFollow = new FormFirstAndFollow();
}
formFirstAndFollow.getTextData(generatedFirst);
formFirstAndFollow.Show();
}
catch (NoValidGrammerException ee) { MessageBox.Show(ee.Message, ee.Message); }
}
public GenerateFollow(InputGrammer inputGrammer, GenerateFirst generatedFirst)
{
foreach (string token in inputGrammer.nonTerminalTokens)
{
followSet.Add(new Production(token, new List <string>()));
}
// 加入$符号
GetValuesByKey(inputGrammer.nonTerminalTokens[0], followSet).Add(ENDSYMBOL);
int changeTotal;
do
{
changeTotal = 0;
foreach (Production production in inputGrammer.userProductions)
{
List <string> valuesInFollow = GetValuesByKey(production.Key, followSet);
for (int i = 0; i < production.Values.Count; i++)
{
string token = production.Values[i];
if (inputGrammer.nonTerminalTokens.Contains(token))
{
List <string> valuesOfTokenInFollow = GetValuesByKey(token, followSet);
if (i != production.Values.Count - 1)
{
bool hasEpsilon = false;
if (ExtendElementWithoutEpsilon(generatedFirst.getFirstFromPart(production.Values, i + 1), valuesOfTokenInFollow, ref hasEpsilon))
{
changeTotal++;
}
if (hasEpsilon && ExtendElement(valuesInFollow, valuesOfTokenInFollow))
{
changeTotal++;
}
}
else if (ExtendElement(valuesInFollow, valuesOfTokenInFollow))
{
changeTotal++;
}
}
}
}
} while (changeTotal != 0);
}
