public static bool Matches(DeclarationTerm term, Ast.Node node)
{
if (term.Type == DeclarationTermType.Keyword || term.Type == DeclarationTermType.Operator)
{
if (node is Ast.Identifier)
return term.Name == (node as Ast.Identifier).Name.Value.ToUpper();
else if (node is Ast.MemberAccess.DummyKeyword)
return term.Name == (node as Ast.MemberAccess.DummyKeyword).Name;
return false;
}
return true;
}
internal static DeclarationTerm ParseDeclarationTerm(TokenStream Stream)
{
DeclarationTerm r = null;
var start = Stream.Next();
if (Stream.Next().Type == TokenType.Identifier)
{
r = new DeclarationTerm
{
Name = Stream.Next().Value.ToUpper(),
Type = DeclarationTermType.Keyword,
RepetitionType = DeclarationTermRepetitionType.Once
};
Stream.Advance();
}
else if (Stream.Next().Type == TokenType.Operator)
{
r = new DeclarationTerm
{
Name = Stream.Next().Value.ToUpper(),
Type = DeclarationTermType.Operator,
RepetitionType = DeclarationTermRepetitionType.Once
};
Stream.Advance();
}
else if (Stream.Next().Type == TokenType.OpenParen)
{
Stream.Advance();
if (Stream.Next().Type != TokenType.Identifier)
throw new CompileError("[021] Expected identifier", start);
r = new DeclarationTerm
{
Name = Stream.Next().Value.ToUpper(),
Type = DeclarationTermType.Term,
RepetitionType = DeclarationTermRepetitionType.Once
};
Stream.Advance();
if (Stream.Next().Type == TokenType.Colon)
{
Stream.Advance();
if (Stream.Next().Type != TokenType.Identifier)
throw new CompileError("[022] Expected identifier", start);
var declaredType = Stream.Next().Value;
r.DeclaredTypeName = declaredType.ToUpper();
Stream.Advance();
}
if (Stream.Next().Type != TokenType.CloseParen)
throw new CompileError("[023] Expected )", start);
Stream.Advance();
}
else
throw new CompileError("[025] Illegal token in declaration header", start);
if (!Stream.AtEnd())
{
if (Stream.Next().Type == TokenType.QuestionMark)
{
var marker = Stream.Next();
var repetitionMarker = Stream.Next().Value;
Stream.Advance();
if (repetitionMarker == "?")
{
if (r.Type != DeclarationTermType.Keyword)
throw new CompileError("[026] Only keywords can be optional in a declaration header", Stream);
r.RepetitionType = DeclarationTermRepetitionType.Optional;
}
//Left over from when terms could be repeated.
//else if (repetitionMarker == "+")
// r.RepetitionType = DeclarationTermRepetitionType.OneOrMany;
//else if (repetitionMarker == "*")
// r.RepetitionType = DeclarationTermRepetitionType.NoneOrMany;
else
throw new CompileError("[027] Unrecognized repetition marker on declaration term", marker);
}
}
return r;
}