/// <summary>
/// Parser for Predicate
/// </summary>
/// <returns>Parsed Predicate</returns>
public Predicate ParsePredicate()
{
Predicate predicate = null; //Empty predicate
if (TokenStream.HasNext() && TokenStream.Peek(1).GetValue().ToString() == "!")
{ //Not Predicate
NotPredicate notPredicate = new NotPredicate();
//Skip ! token
NextToken("!", "! predicate", '!');
//Parse predicate after !
notPredicate.SetPredicate(ParsePredicate());
predicate = notPredicate;
}
else
{ //Other predicates exists out of an expression
Expression expression = expressionParser.ParseExpression();
if (TokenStream.HasNext() && TokenStream.Peek(1).GetValue().ToString() == ".")
{ //IsPredicate
predicate = ParseIsPredicate(expression);
}
else
{ //ExpressionPredicate
predicate = ParseExpressionPredicate(expression);
}
}
//Check for && or || predicates
if (TokenStream.HasNext() && TokenStream.Peek(1).GetValue().ToString() == "&" && TokenStream.Peek(2).GetValue().ToString() == "&")
{ //AndPredicate
return ParseAndPredicate(predicate);
}
else if (TokenStream.HasNext() && TokenStream.Peek(1).GetValue().ToString() == "|" && TokenStream.Peek(2).GetValue().ToString() == "|")
{ //OrPredicate
return ParseOrPredicate(predicate);
}
return predicate;
}
public virtual void Visit(NotPredicate predicate)
{
VisitSubNodes(predicate);
}