private MyArrayList TotalRuleFollowSet(RuleStart rs)
{
MyArrayList res = new MyArrayList();
rs = GoToFirstStartRule(rs);
while (rs != null)
{
res = ParseHelper.UnionSet(res, rs.GetRuleConnect().FollowSet);
rs = rs.GetAlternate();
}
return(res);
}
private bool IsLeftRecursionInStartToken(RuleStart rs)
{
while (rs != null)
{
if (IsRuleLeftRekursiv(rs))
{
return(true);
}
rs = rs.GetAlternate();
}
return(false);
}
// protected virtual void GenerateAllFirstSets()
// {
// for(int i=0;i<m_Rules.Count;i++)
// {
// BNFRule bnfRl = (BNFRule)m_Rules[i];
// RuleStart strt = bnfRl.GetStart();
// strt.GetRuleConnect().FirstSet = GenerateFirstSet(strt);
// }
// }
// protected virtual void CheckEpsilonInRules()
// {
// for(int i=0;i<m_Rules.Count;i++)
// {
// BNFRule bnfRl = (BNFRule)m_Rules[i];
// RuleStart strt = bnfRl.GetStart();
// RuleIsEpsilonFree(strt);
// }
// }
protected bool TotalRuleEpsFree(RuleStart rs)
{
rs = GoToFirstStartRule(rs);
while (rs != null)
{
if (!rs.GetRuleConnect().EpsilonFree)
{
return(false);
}
rs = rs.GetAlternate();
}
return(true);
}
protected virtual MyArrayList GenerateFirstSet(RuleStart rs)
{
MyArrayList res = new MyArrayList();
RuleElement re = null;
if (rs != null)
{
re = rs.GetNext();
}
else
{
return(null);
}
while (re != null)
{
if (re.GetToken().Equals(""))
{
re = re.GetNext();
}
else
{
if (re.IsTerminal())
{
res.Add(re);
return(res);
}
else
{
RuleToken rt = (RuleToken)re;
RuleStart conStr = GoToFirstStartRule(rt.GetConnected());
MyArrayList res2 = null;
while (conStr != null)
{
res2 = GenerateFirstSet(conStr);
res = ParseHelper.UnionSet(res, res2);
conStr = conStr.GetAlternate();
}
if (TotalRuleEpsFree(rt.GetConnected()))
{
return(res);
}
else
{
re = re.GetNext();
}
}
}
}
return(res);
}
private void DeleteStartRule(RuleStart rs)
{
BNFRule bnfRl = rs.GetRuleConnect();
RuleStart AltNext = rs.GetAlternate();
RuleStart AltBack = rs.GetAlternateBack();
if (AltBack != null)
{
AltBack.SetAlternate(AltNext);
}
if (AltNext != null)
{
AltNext.SetAlternateBack(AltBack);
}
int index = bnfRl.Index;
m_Rules.RemoveAt(index);
}
private bool SetAllFollows(RuleStart rs, MyArrayList Follows)
{
bool changed = false;
rs = GoToFirstStartRule(rs);
while (rs != null)
{
int FlwSize = 0;
if (rs.GetRuleConnect().FollowSet != null)
{
FlwSize = rs.GetRuleConnect().FollowSet.Count;
}
rs.GetRuleConnect().FollowSet = ParseHelper.UnionSet(rs.GetRuleConnect().FollowSet, Follows);
FlwSize = rs.GetRuleConnect().FollowSet.Count - FlwSize;
if (FlwSize != 0)
{
changed = true;
}
rs = rs.GetAlternate();
}
return(changed);
}
private void EleminateDirectLeftRecursion(RuleStart strt)
{
string ElemStartTkn = "";
if (strt != null)
{
ElemStartTkn = FindUnusedToken(strt.GetToken());
}
while (strt != null)
{
if (IsRuleLeftRekursiv(strt))
{
RuleElement re = strt.GetNext();
if (re != null)
{
strt.SetNext(re.GetNext());
re = GotoLastRule(strt);
re.SetNext(new RuleToken(ElemStartTkn, strt));
strt.SetToken(ElemStartTkn);
}
BNFRule bnfRl = new BNFRule(m_Rules.Count);
bnfRl.SetStart(ElemStartTkn);
bnfRl.GetStart().SetNext(new RuleEpsilon(bnfRl.GetStart()));
m_Rules.Add(bnfRl);
}
else
{
RuleElement re = strt.GetNext();
if (re != null)
{
re = GotoLastRule(strt);
re.SetNext(new RuleToken(ElemStartTkn, strt));
}
}
strt = strt.GetAlternate();
}
}
