ProfNode ParseRegex()
{
ProfNode root = null;
while (true)
{
ProfNode exp = ParseConcatExp();
if (exp == null)
{
return(exp);
}
if (root == null)
{
root = exp;
}
else
{
root = new ProfNode('|', root, exp);
}
if (_cursor.Current == '|')
{
_cursor.Next();
}
else
{
return(root);
}
}
}
ProfNode ParseCharExp()
{
if (!char.IsLetterOrDigit(_cursor.Current))
{
return(null);
}
ProfNode node = new ProfNode(_cursor.Current, null, null);
return(node);
}
public ProfNode Parse()
{
ProfNode exp = ParseRegex();
if (exp == null)
{
return(null);
}
if (_cursor.Current == 0)
{
return(null);
}
return(null);
}
ProfNode ParseStartExp()
{
ProfNode exp = ParseStarizableExp();
if (exp == null)
{
return(null);
}
if (_cursor.Current == '*')
{
exp = new ProfNode('*', exp);
}
return(exp);
}
ProfNode ParseParenthesisExp()
{
if (_cursor.Current != '(')
{
return(null);
}
_cursor.Next();
ProfNode exp = ParseRegex();
if (_cursor.Current != ')')
{
return(null);
}
_cursor.Next();
return(exp);
}
ProfNode ParseConcatExp()
{
ProfNode root = null;
do
{
ProfNode exp = ParseStartExp();
if (root == null)
{
root = exp;
}
else
{
root = new ProfNode('+', root, exp);
}
if (exp == null)
{
return(null);
}
} while (_cursor.Current == '(' || char.IsLetterOrDigit(_cursor.Current));
return(root);
}
public ProfNode(char symbol, ProfNode left)
: this(symbol, left, null)
{
}
public ProfNode(char symbol, ProfNode left, ProfNode right)
{
_symbol = symbol;
_left = left;
_right = right;
}
