public override EpsilonNfa Apply(PositiveExpression expression, Automaton param)
{
var nfa = new EpsilonNfa(param);
var body = Invoke(expression.Matched, param);
param.AddTransition(nfa.Start, body.Start, Transition.Type.Positive);
param.AddTransition(body.End, nfa.End, Transition.Type.End);
return(nfa);
}
Expression ParseFunction()
{
if (_sourceWindow.AdvanceIfMatches("(="))
{
var sub = ParseExpression();
if (!_sourceWindow.AdvanceIfMatches(')'))
{
throw new ArgumentException(") lost");
}
var exp = new PositiveExpression(sub);
return(exp);
}
else if (_sourceWindow.AdvanceIfMatches("(!"))
{
var sub = ParseExpression();
if (!_sourceWindow.AdvanceIfMatches(')'))
{
throw new ArgumentException(") lost");
}
var exp = new NegativeExpression(sub);
return(exp);
}
else if (_sourceWindow.AdvanceIfMatches("(<&"))
{
//表达式引用
string name;
if (!_sourceWindow.AdvanceIfName(out name))
{
throw new ArgumentException("invalid name.");
}
if (!_sourceWindow.AdvanceIfMatches('>'))
{
throw new ArgumentException("> lost.");
}
if (!_sourceWindow.AdvanceIfMatches(')'))
{
throw new ArgumentException(") lost.");
}
var exp = new ReferenceExpression(name);
return(exp);
}
else if (_sourceWindow.AdvanceIfMatches("(<$"))
{
string name;
int index = -1;
if (_sourceWindow.AdvanceIfName(out name))
{
if (_sourceWindow.AdvanceIfMatches(';'))
{
if (!_sourceWindow.AdvanceIfPositiveInteger(out index))
{
throw new ArgumentException("Positive numbers required after ;");
}
}
}
else if (!_sourceWindow.AdvanceIfPositiveInteger(out index))
{
throw new ArgumentException("Positive numbers required after (<$");
}
if (!_sourceWindow.AdvanceIfMatches('>'))
{
throw new ArgumentException("> lost.");
}
if (!_sourceWindow.AdvanceIfMatches(')'))
{
throw new ArgumentException(") lost.");
}
var exp = new MatchExpression(name, index);
return(exp);
}
else if (_sourceWindow.AdvanceIfMatches("(<"))
{
string name;
if (!_sourceWindow.AdvanceIfName(out name))
{
throw new ArgumentException("Name lost");
}
if (!_sourceWindow.AdvanceIfMatches('>'))
{
throw new ArgumentException("> lost");
}
var sub = ParseExpression();
if (!_sourceWindow.AdvanceIfMatches(')'))
{
throw new ArgumentException(") lost");
}
var exp = new CaptureExpression(name, sub);
return(exp);
}
else if (_sourceWindow.AdvanceIfMatches("(?"))
{
var sub = ParseExpression();
if (_sourceWindow.AdvanceIfMatches(')'))
{
throw new ArgumentException(") lost");
}
var exp = new CaptureExpression(sub);
return(exp);
}
else if (_sourceWindow.AdvanceIfMatches('('))//subexpression
{
var exp = ParseExpression();
if (!_sourceWindow.AdvanceIfMatches(')'))
{
throw new ArgumentException(") lost");
}
return(exp);
}
else
{
return(null);
}
}
public override Expression Apply(PositiveExpression expression, MergeParameter param)
{
return(new PositiveExpression(
Invoke(expression, param)));
}
public bool Equals(PositiveExpression obj)
{
return(Matched.Equals(obj.Matched));
}
public void Visit(PositiveExpression expression)
{
_returnValue = this.Apply(expression, _paramValue);
}
public abstract ReturnT Apply(PositiveExpression expression, ParamT param);
Expression ParseFunction()
{
if (_sourceWindow.AdvanceIfMatches("(="))
{
var sub = ParseExpression();
if (!_sourceWindow.AdvanceIfMatches(')'))
{
throw new ArgumentException(") lost");
}
var exp = new PositiveExpression(sub);
return exp;
}
else if (_sourceWindow.AdvanceIfMatches("(!"))
{
var sub = ParseExpression();
if (!_sourceWindow.AdvanceIfMatches(')'))
{
throw new ArgumentException(") lost");
}
var exp = new NegativeExpression(sub);
return exp;
}
else if (_sourceWindow.AdvanceIfMatches("(<&"))
{
//表达式引用
string name;
if (!_sourceWindow.AdvanceIfName(out name))
{
throw new ArgumentException("invalid name.");
}
if (!_sourceWindow.AdvanceIfMatches('>'))
{
throw new ArgumentException("> lost.");
}
if (!_sourceWindow.AdvanceIfMatches(')'))
{
throw new ArgumentException(") lost.");
}
var exp = new ReferenceExpression(name);
return exp;
}
else if (_sourceWindow.AdvanceIfMatches("(<$"))
{
string name;
int index = -1;
if (_sourceWindow.AdvanceIfName(out name))
{
if (_sourceWindow.AdvanceIfMatches(';'))
{
if (!_sourceWindow.AdvanceIfPositiveInteger(out index))
{
throw new ArgumentException("Positive numbers required after ;");
}
}
}
else if (!_sourceWindow.AdvanceIfPositiveInteger(out index))
{
throw new ArgumentException("Positive numbers required after (<$");
}
if (!_sourceWindow.AdvanceIfMatches('>'))
{
throw new ArgumentException("> lost.");
}
if (!_sourceWindow.AdvanceIfMatches(')'))
{
throw new ArgumentException(") lost.");
}
var exp = new MatchExpression(name, index);
return exp;
}
else if (_sourceWindow.AdvanceIfMatches("(<"))
{
string name;
if (!_sourceWindow.AdvanceIfName(out name))
{
throw new ArgumentException("Name lost");
}
if (!_sourceWindow.AdvanceIfMatches('>'))
{
throw new ArgumentException("> lost");
}
var sub = ParseExpression();
if (!_sourceWindow.AdvanceIfMatches(')'))
{
throw new ArgumentException(") lost");
}
var exp = new CaptureExpression(name, sub);
return exp;
}
else if (_sourceWindow.AdvanceIfMatches("(?"))
{
var sub = ParseExpression();
if (_sourceWindow.AdvanceIfMatches(')'))
{
throw new ArgumentException(") lost");
}
var exp = new CaptureExpression(sub);
return exp;
}
else if (_sourceWindow.AdvanceIfMatches('('))//subexpression
{
var exp = ParseExpression();
if (!_sourceWindow.AdvanceIfMatches(')'))
{
throw new ArgumentException(") lost");
}
return exp;
}
else return null;
}
public bool Equals(PositiveExpression obj)
{
return Matched.Equals(obj.Matched);
}
