public static cSet <cLexem> cm_FirstTerminals(List <cLexem> a_listLexem)
{
cSet <cLexem> _tempSet = new cSet <cLexem>();
if (a_listLexem.Count > 0)
{
int _pos = 0;
cLexem _currLexem = a_listLexem[_pos];
do
{
_tempSet.Remove(cLexem.cc_EpsilonLexem);
_currLexem = a_listLexem[_pos];
_tempSet.UnionWith(_currLexem.cp_FirstCache);
_pos++;
} while (_tempSet.Contains(cLexem.cc_EpsilonLexem) && (_pos < a_listLexem.Count));
}
cSet <cLexem> _retSet = new cSet <cLexem>();
foreach (cLexem _lexem in _tempSet)
{
if (_lexem.cp_Type != eLexType.NonTerminal)
{
_retSet.Add(_lexem);
}
}
return(_retSet);
}
public object Clone()
{
cSet <T> _retSet = new cSet <T>();
_retSet.UnionWith(this);
return(_retSet);
}
private cSet <cLexem> cm_First(List <cLexem> a_listLexem)
{
cSet <cLexem> _retSet = new cSet <cLexem>();
if (a_listLexem.Count > 0)
{
int _pos = a_listLexem.Count - 1;
cLexem _currLexem = a_listLexem[_pos];
do
{
_retSet.Remove(cLexem.cc_EpsilonLexem);
_currLexem = a_listLexem[_pos];
_retSet.UnionWith(_currLexem.cp_FirstCache);
_pos--;
} while (_retSet.Contains(cLexem.cc_EpsilonLexem) && (_pos >= 0));
}
return(_retSet);
}
private Dictionary <cLexem, cSet <cLexem> > cm_Follow()
{
Dictionary <cLexem, cSet <cLexem> > _retDic = new Dictionary <cLexem, cSet <cLexem> >();
foreach (cLexem _nonTerminal in cp_Lexems)
{
if (_nonTerminal.cp_Type == eLexType.NonTerminal)
{
_retDic[_nonTerminal] = new cSet <cLexem>();
}
}
_retDic[cf_root].Add(cLexem.cc_StopLexem);
// 2
foreach (cLexem _nonTerminal in _retDic.Keys)
{
foreach (cProduction _production in _nonTerminal.cp_ListProducts)
{
int _count = _production.cp_RightPart.Count - 1;
List <cLexem> _revListProduct = new List <cLexem>();
for (int i = _count; i >= 0; i--)
{
cLexem _lex = _production.cp_RightPart[i];
switch (_lex.cp_Type)
{
case eLexType.NonTerminal:
cSet <cLexem> _first = cm_First(_revListProduct);
_first.Remove(cLexem.cc_EpsilonLexem);
_retDic[_lex].AddRange(_first);
break;
default:
break;
}
_revListProduct.Add(_lex);
}
}
}
// 3
bool _added = true;
while (_added)
{
_added = false;
foreach (cLexem _nonTerminal in _retDic.Keys)
{
foreach (cProduction _production in _nonTerminal.cp_ListProducts)
{
int _count = _production.cp_RightPart.Count - 1;
List <cLexem> _revListProduct = new List <cLexem>();
bool _break = false; //?
for (int i = _count; i >= 0; i--)
{
cLexem _lex = _production.cp_RightPart[i];
switch (_lex.cp_Type)
{
case eLexType.NonTerminal:
cSet <cLexem> _first = cm_First(_revListProduct);
if (_first.Contains(cLexem.cc_EpsilonLexem) | (i == _count))
{
//_production.cp_Root.cm_First(_first);
//_first.UnionWith(_production.cp_Root.cp_FirstCache);
_first.Remove(cLexem.cc_EpsilonLexem);
_first.UnionWith(_retDic[_nonTerminal]);
}
_added |= _retDic[_lex].AddRange(_first);
break;
case eLexType.Action:
break;
default:
_break = true;
break;
}
_revListProduct.Add(_lex);
if (_break)
{
break;
}
}
}
}
}
return(_retDic);
}