public static Pair <HashSet <char>, Automaton <BDD> > parseRegexFromXML(XElement regex, XElement alphabet, CharSetSolver solver)
{
HashSet <char> al = new HashSet <char>();
XElement xmlAlphabet = XElement.Parse(RemoveAllNamespaces(alphabet.ToString()));
string alRex = "";
bool first = true;
foreach (XElement child in xmlAlphabet.Elements())
{
char element = Convert.ToChar(child.Value);
al.Add(element);
if (first)
{
first = false;
alRex += element;
}
else
{
alRex += "|" + element;
}
}
XElement Regex = XElement.Parse(RemoveAllNamespaces(regex.ToString()));
string rexpr = Regex.Value.Trim();
var escapedRexpr = string.Format(@"^({0})$", rexpr);
Automaton <BDD> aut = null;
try
{
aut = solver.Convert(escapedRexpr);
}
catch (ArgumentException e)
{
throw new PDLException("The input is not a well formatted regular expression: " + e.Message);
}
catch (AutomataException e)
{
throw new PDLException("The input is not a well formatted regular expression: " + e.Message);
}
var diff = aut.Intersect(solver.Convert(@"^(" + alRex + @")*$").Complement(solver), solver);
if (!diff.IsEmpty)
{
throw new PDLException(
"The regular expression should only accept strings over (" + alRex + ")*. Yours accepts the string '" + DFAUtilities.GenerateShortTerm(diff.Determinize(solver), solver) + "'");
}
return(new Pair <HashSet <char>, Automaton <BDD> >(al, aut));
}
