public void CurrentTest()
{
Write("current.txt", "scary Variable ");
StreamReader stream = new StreamReader("C:\\current.txt");
scanner = new PrologScanner(stream);
scanner.Next();
Assert.AreEqual(PrologToken.ATOM, scanner.Current.Kind);
scanner.Next();
Assert.AreEqual(PrologToken.VARIABLE, scanner.Current.Kind);
stream.Close();
}
public PrologCodeUnit Parse(TextReader input)
{
_scanner = new PrologScanner(input);
_errors.Clear();
PrologCodeTerm term = null;
while (true)
{
term = ReadTerm(1200);
if (_scanner.Next().Kind != PrologToken.DOT)
{
_errors.Add(new PrologCompilerError("P0001", "Unexpected end of term", "", false, _scanner.Current.Line, _scanner.Current.Column));
break;
}
if (term is PrologCodeHeadlessClause)
{
ProcessHeadlessClause(term);
}
else
{
_codeUnit.Terms.Add(term);
}
if (_scanner.Lookahead.Kind == PrologToken.EOF)
{
break;
}
}
return(_codeUnit);
}
public void DotTest()
{
Write("dot.txt", " . ");
StreamReader stream = new StreamReader("C:\\dot.txt");
scanner = new PrologScanner(stream);
scanner.Next();
Assert.AreEqual(PrologToken.DOT, scanner.Current.Kind);
stream.Close();
}
public void CommaTest()
{
Write("comma.txt", " , ");
StreamReader stream = new StreamReader("C:\\comma.txt");
scanner = new PrologScanner(stream);
scanner.Next();
Assert.AreEqual(PrologToken.COMMA, scanner.Current.Kind);
stream.Close();
}
public void AtomTest()
{
Write("atom.txt", " atom ");
StreamReader stream = new StreamReader("C:\\atom.txt");
scanner = new PrologScanner(stream);
scanner.Next();
Assert.AreEqual(PrologToken.ATOM, scanner.Current.Kind);
stream.Close();
}
public void FactTokensRule()
{
Write("fact_tokens.txt", "male(ali,hodroj,X,'Fine not really!',[A|B]).");
StreamReader stream = new StreamReader("C:\\fact_tokens.txt");
scanner = new PrologScanner(stream);
// male
scanner.Next();
Assert.AreEqual(PrologToken.ATOM, scanner.Current.Kind);
// (
scanner.Next();
Assert.AreEqual(PrologToken.LPAREN, scanner.Current.Kind);
// ali
scanner.Next();
Assert.AreEqual(PrologToken.ATOM, scanner.Current.Kind);
// ,
scanner.Next();
Assert.AreEqual(PrologToken.COMMA, scanner.Current.Kind);
// hodroj
scanner.Next();
Assert.AreEqual(PrologToken.ATOM, scanner.Current.Kind);
// ,
scanner.Next();
Assert.AreEqual(PrologToken.COMMA, scanner.Current.Kind);
// X
scanner.Next();
Assert.AreEqual(PrologToken.VARIABLE, scanner.Current.Kind);
// ,
scanner.Next();
Assert.AreEqual(PrologToken.COMMA, scanner.Current.Kind);
// 'Fine Not Really!'
scanner.Next();
Assert.AreEqual(PrologToken.ATOM, scanner.Current.Kind);
// ,
scanner.Next();
Assert.AreEqual(PrologToken.COMMA, scanner.Current.Kind);
// [
scanner.Next();
Assert.AreEqual(PrologToken.LBRACKET, scanner.Current.Kind);
// A
scanner.Next();
Assert.AreEqual(PrologToken.VARIABLE, scanner.Current.Kind);
// |
scanner.Next();
Assert.AreEqual(PrologToken.LIST_SEP, scanner.Current.Kind);
// B
scanner.Next();
Assert.AreEqual(PrologToken.VARIABLE, scanner.Current.Kind);
// ]
scanner.Next();
Assert.AreEqual(PrologToken.RBRACKET, scanner.Current.Kind);
// )
scanner.Next();
Assert.AreEqual(PrologToken.RPAREN, scanner.Current.Kind);
// .
scanner.Next();
Assert.AreEqual(PrologToken.DOT, scanner.Current.Kind);
stream.Close();
}
public void VariableTest()
{
Write("var.txt", "Father ");
StreamReader stream = new StreamReader("C:\\var.txt");
scanner = new PrologScanner(stream);
scanner.Next();
Assert.AreEqual(PrologToken.VARIABLE, scanner.Current.Kind);
stream.Close();
}
public void StringTest()
{
Write("string.txt", " 'This is a string' ");
StreamReader stream = new StreamReader("C:\\string.txt");
scanner = new PrologScanner(stream);
scanner.Next();
Assert.AreEqual(PrologToken.ATOM, scanner.Current.Kind);
stream.Close();
}
public void RParenTest()
{
Write("rparen.txt", " ) ");
StreamReader stream = new StreamReader("C:\\rparen.txt");
scanner = new PrologScanner(stream);
scanner.Next();
Assert.AreEqual(PrologToken.RPAREN, scanner.Current.Kind);
stream.Close();
}
public void RBracketTest()
{
Write("rbra.txt", " ] ");
StreamReader stream = new StreamReader("C:\\rbra.txt");
scanner = new PrologScanner(stream);
scanner.Next();
Assert.AreEqual(PrologToken.RBRACKET, scanner.Current.Kind);
stream.Close();
}
public void ListSepTest()
{
Write("sep.txt", " | ");
StreamReader stream = new StreamReader("C:\\sep.txt");
scanner = new PrologScanner(stream);
scanner.Next();
Assert.AreEqual(PrologToken.LIST_SEP, scanner.Current.Kind);
stream.Close();
}
public BinaryTree Term(int n)
{
int m = 0;
BinaryTree ast = null;
_scanner.Next();
switch (_scanner.Current.Kind)
{
case PrologToken.LPAREN:
ast = Term(1200);
_scanner.Next();
if (_scanner.Current.Kind != PrologToken.RPAREN)
{
_errors.Add(new PrologCompilerError("P0003", "Expected ) after term", "", false, _scanner.Current.Line, _scanner.Current.Column));
}
break;
// Handle list terms here...
case PrologToken.LBRACKET:
ArrayList listArguments = new ArrayList();
// Peek after [ token
if (_scanner.Lookahead.Kind == PrologToken.RBRACKET)
{
_scanner.Next();
// return a nil atom: []
ast = new BinaryList(); // empty list
break;
}
listArguments.Add(Term(999));
_scanner.Next();
// if , is encountered
while (_scanner.Current.Kind == PrologToken.COMMA)
{
listArguments.Add(Term(999));
_scanner.Next();
}
if (_scanner.Current.Kind == PrologToken.LIST_SEP)
{
listArguments.Add(Term(999));
_scanner.Next();
}
else
{
listArguments.Add(new BinaryList());
}
if (_scanner.Current.Kind != PrologToken.RBRACKET)
{
_errors.Add(new PrologCompilerError("P0004", "Unterminated list, expected ]", "", false, _scanner.Current.Line, _scanner.Current.Column));
}
int i = listArguments.Count - 1;
BinaryList list = new BinaryList((BinaryTree)listArguments[i - 1], (BinaryTree)listArguments[i]);
i -= 2;
while (i > -1)
{
list = new BinaryList((BinaryTree)listArguments[i--], list);
}
ast = list;
break;
case PrologToken.RPAREN:
case PrologToken.RBRACKET:
case PrologToken.COMMA:
case PrologToken.DOT:
_errors.Add(new PrologCompilerError("P0005", "Unexpected closure of term", "", false, _scanner.Current.Line, _scanner.Current.Column));
return(null);
case PrologToken.ATOM:
case PrologToken.VARIABLE:
string atomName = _scanner.Current.StringValue;
if (_scanner.Lookahead.Kind == PrologToken.LPAREN)
{
ArrayList arguments = new ArrayList();
_scanner.Next();
arguments.Add(Term(1200));
_scanner.Next();
while (_scanner.Current.Kind == PrologToken.COMMA)
{
arguments.Add(Term(1200));
_scanner.Next();
}
if (_scanner.Current.Kind != PrologToken.RPAREN)
{
_errors.Add(new PrologCompilerError("P0005", "Unexpected closure of term", "", false, _scanner.Current.Line, _scanner.Current.Column));
return(null);
}
ast = new BinaryTree(atomName, arguments);
break;
}
if (_operators.IsOperator(_scanner.Current.StringValue))
{
PrologOperator op = _operators.GetOperator(_scanner.Current.StringValue);
if (op.IsPrefix)
{
// prefix operator
if (n < op.PrefixPrecedence)
{
ParserError("prefix precedence error", _scanner.Current.Line, _scanner.Current.Column);
return(null);
}
switch (_scanner.Lookahead.Kind)
{
case PrologToken.LPAREN:
case PrologToken.LBRACKET:
ast = new BinaryTree(op.Name, Term(op.PrefixRightPrecedence));
m = op.PrefixPrecedence;
Right(n, m, ref ast);
break;
case PrologToken.RPAREN:
case PrologToken.RBRACKET:
case PrologToken.DOT:
case PrologToken.LIST_SEP:
if (n < m)
{
_errors.Add(new PrologCompilerError("P0006", "Unexpected atom '" + _scanner.Lookahead.StringValue + "'", "", false, _scanner.Current.Line, _scanner.Current.Column));
return(null);
}
ast = new BinaryTree(_scanner.Current.StringValue);
Right(n, m, ref ast);
break;
case PrologToken.ATOM:
if (_operators.IsOperator(_scanner.Lookahead.StringValue))
{
PrologOperator atomOp = _operators.GetOperator(_scanner.Lookahead.StringValue);
if (atomOp.IsInfix && m <= atomOp.InfixLeftPrecedence)
{
if (n < m)
{
ParserError("n < m", _scanner.Lookahead.Line, _scanner.Current.Column);
return(null);
}
ast = new BinaryTree(_scanner.Lookahead.StringValue);
Right(n, m, ref ast);
break;
}
else if (atomOp.IsPostfix && m <= atomOp.PostfixLeftPrecedence)
{
if (n < m)
{
ParserError("n < m", _scanner.Current.Line, _scanner.Current.Column);
return(null);
}
ast = new BinaryTree(_scanner.Current.StringValue);
Right(n, m, ref ast);
break;
}
// Just added on 6/23/2006. Might not fix anything.
else
{
ast = new BinaryTree(_scanner.Current.StringValue, null, Term(op.InfixRightPrecedence));
m = op.PrefixPrecedence;
Right(n, m, ref ast);
break;
}
}
else
{
ast = new BinaryTree(_scanner.Current.StringValue, null, Term(op.InfixRightPrecedence));
m = op.PrefixPrecedence;
Right(n, m, ref ast);
}
break;
default:
ParserError("Unknown internal error", _scanner.Current.Line, _scanner.Current.Column);
return(null);
}
}
}
else
{
ast = new BinaryTree(_scanner.Current.StringValue);
}
break;
default:
ParserError("Unknown internal error", _scanner.Current.Line, _scanner.Current.Column);
return(null);
}
Right(n, m, ref ast);
return(ast);
}
public PrologCodeUnit Parse(TextReader input)
{
_scanner = new PrologScanner(input);
_errors.Clear();
PrologCodeTerm term = null;
while(true)
{
term = ReadTerm(1200);
if (_scanner.Next().Kind != PrologToken.DOT)
{
_errors.Add(new PrologCompilerError("P0001", "Unexpected end of term", "", false, _scanner.Current.Line, _scanner.Current.Column));
break;
}
if (term is PrologCodeHeadlessClause)
{
ProcessHeadlessClause(term);
}
else
{
_codeUnit.Terms.Add(term);
}
if (_scanner.Lookahead.Kind == PrologToken.EOF)
break;
}
return _codeUnit;
}
