void ScanBlock(RandomAccessIterator <SourceLine> lines)
{
var ix = lines.Index;
var line = lines.Current;
var closures = new Stack <Token>();
closures.Push(line.Instruction);
while (lines.MoveNext() && closures.Count > 0)
{
if (lines.Current.Instruction != null)
{
if (lines.Current.Instruction.Name.Equals(_openClosures[closures.Peek().Name], Services.StringViewComparer))
{
closures.Pop();
}
else if (_openClosures.ContainsKey(lines.Current.Instruction.Name))
{
closures.Push(lines.Current.Instruction);
}
}
}
if (closures.Count > 0)
{
throw new SyntaxException(closures.Peek(),
$"Missing closure \"{_openClosures[closures.Peek().Name]}\" for directive \"{closures.Peek().Name}\".");
}
lines.SetIndex(ix);
}
/// <summary>
/// Determines whether the tokenized expression is a string.
/// </summary>
/// <param name="iterator">The iterator to the tokenized expression.</param>
/// <param name="services">The shared assembly services.</param>
/// <returns></returns>
public static bool ExpressionIsAString(RandomAccessIterator <Token> iterator, AssemblyServices services)
{
var token = iterator.Current;
if (token.IsDoubleQuote())
{
return(token.Name.Length > 2 && Token.IsEnd(iterator.PeekNext()));
}
var ix = iterator.Index;
var result = false;
if (token.Type == TokenType.Function &&
(token.Name.Equals("format", services.StringComparison) || token.Name.Equals("char", services.StringComparison)))
{
iterator.MoveNext();
var parms = Token.GetGroup(iterator);
var last = iterator.Current;
result = Token.IsEnd(last);
if (token.Name.Equals("char", services.StringComparison))
{
result &= services.Evaluator.Evaluate(parms.GetIterator(), 0, 0x10FFFF).IsInteger();
}
}
else if (token.Type == TokenType.Operand &&
(char.IsLetter(token.Name[0]) || token.Name[0] == '_') &&
!services.Evaluator.IsReserved(token.Name))
{
var sym = services.SymbolManager.GetSymbol(token, false);
if (sym != null)
{
if (iterator.MoveNext() && iterator.Current.Name.Equals("["))
{
var subscript = (int)services.Evaluator.Evaluate(iterator);
result = Token.IsEnd(iterator.Current) &&
subscript >= 0 && subscript < sym.StringVector.Count;
}
else
{
result = Token.IsEnd(iterator.Current) &&
sym.StorageType == StorageType.Scalar &&
sym.DataType == DataType.String;
}
}
}
iterator.SetIndex(ix);
return(result);
}