internal static IDeclCmd?VisitDeclCmd(VCDLexer lexer, IDToVarDef idToVariable, Stack <Scope> scopes)
{
ReadOnlySpan <byte> declWord = lexer.NextWord();
Span <char> chars = stackalloc char[declWord.Length];
declWord.CopyToCharArray(chars);
ReadOnlySpan <byte> endToken = new byte[] { (byte)'$', (byte)'e', (byte)'n', (byte)'d' };
ReadOnlySpan <byte> dollarSign = new byte[] { (byte)'$' };
if (chars.SequenceEqual("$comment"))
{
string text = lexer.NextUntil(endToken).ToCharString();
lexer.ExpectNextWord(endToken);
return(new Comment(text));
}
else if (chars.SequenceEqual("$date"))
{
string text = lexer.NextUntil(endToken).ToCharString();
lexer.ExpectNextWord(endToken);
return(new Date(text));
}
else if (chars.SequenceEqual("$scope"))
{
ScopeType type = VisitScopeType(lexer);
string id = lexer.NextWord().ToCharString();
Scope scope = new Scope(type, id);
scopes.Push(scope);
lexer.ExpectNextWord(endToken);
return(scope);
}
else if (chars.SequenceEqual("$timescale"))
{
int scale = VisitTimeNumber(lexer);
TimeUnit unit = VisitTimeUnit(lexer);
lexer.ExpectNextWord(endToken);
return(new TimeScale(scale, unit));
}
else if (chars.SequenceEqual("$upscope"))
{
scopes.Pop();
lexer.ExpectNextWord(endToken);
return(new UpScope());
}
else if (chars.SequenceEqual("$var"))
{
VarType type = VisitVarType(lexer);
int size = VisitSize(lexer);
string id = lexer.NextWord().ToCharString();
string reference = lexer.NextWord().ToCharString();
VarDef variable = new VarDef(type, size, id, reference, scopes.Reverse().ToArray());
idToVariable.AddVariable(variable);
//Skip this stuff because it's not currently supported
char nextChar = lexer.PeekNextChar();
if (nextChar == '[')
{
ReadOnlySpan <byte> endBracket = new byte[] { (byte)']' };
lexer.NextUntil(endBracket);
lexer.SkipChar();
}
lexer.ExpectNextWord(endToken);
return(variable);
}
else if (chars.SequenceEqual("$version"))
{
string versionTxt = lexer.NextUntil(dollarSign).ToCharString();
string systemTaskString = string.Empty;
ReadOnlySpan <byte> systemTask = lexer.PeekNextWord().Span;
if (systemTask.StartsWith(dollarSign) && !systemTask.SequenceEqual(endToken))
{
lexer.SkipWord(systemTask);
systemTaskString = systemTask.ToCharString();
}
lexer.ExpectNextWord(endToken);
return(new Version(versionTxt, systemTaskString));
}
else if (chars.SequenceEqual("$enddefinitions"))
{
lexer.ExpectNextWord(endToken);
return(null);
}
else
{
throw new Exception($"Invalid declaration command: {declWord.ToCharString()}\nBuffer: {lexer.BufferToString()}");
}
}
