private Node ParseTerminal(ILexer lexer)
{
Node result;
switch (lexer.Token)
{
// Nested
case TokenType.LeftParenthesis:
lexer.ReadToken();
result = ParseConditional(lexer);
if (lexer.Token != TokenType.RightParenthesis)
{
throw new Exception("Unclosed parenthesis");
}
lexer.ReadToken();
break;
// A number
case TokenType.Number:
result = Node.Constant(SpiceHelper.ParseNumber(lexer.Content));
lexer.ReadToken();
break;
// Can be a variable or a function call
case TokenType.Identifier:
string name = lexer.Content;
lexer.ReadToken();
if (lexer.Token == TokenType.LeftParenthesis)
{
// Function call!
string function = null;
switch (name.ToLowerInvariant())
{
case "vr":
function = "real"; goto case "v";
case "vi":
function = "imag"; goto case "v";
case "vm":
function = "abs"; goto case "v";
case "vdb":
function = "db"; goto case "v";
case "vph":
function = "phase"; goto case "v";
case "v":
// Read the nodes
lexer.ReadNode();
result = Node.Voltage(lexer.Content);
lexer.ReadToken();
if (lexer.Token == TokenType.Comma)
{
lexer.ReadNode();
result = Node.Subtract(result, Node.Voltage(lexer.Content));
lexer.ReadToken();
}
if (lexer.Token != TokenType.RightParenthesis)
{
throw new Exception("Invalid voltage specifier");
}
lexer.ReadToken();
break;
case "ir":
function = "real"; goto case "i";
case "ii":
function = "imag"; goto case "i";
case "im":
function = "abs"; goto case "i";
case "idb":
function = "db"; goto case "i";
case "iph":
function = "phase"; goto case "i";
case "i":
// Read the name
lexer.ReadNode();
result = Node.Current(lexer.Content);
lexer.ReadToken();
if (lexer.Token != TokenType.RightParenthesis)
{
throw new Exception("Invalid current specifier");
}
lexer.ReadToken();
break;
default:
var arguments = new List <Node>(2);
// Let's go to the first token after the function call
lexer.ReadToken();
while (lexer.Token != TokenType.RightParenthesis)
{
// Read the argument
arguments.Add(ParseConditional(lexer));
// Continue with another argument
if (lexer.Token == TokenType.Comma)
{
lexer.ReadToken();
}
else if (lexer.Token != TokenType.RightParenthesis)
{
throw new Exception("Invalid function call");
}
}
result = Node.Function(name, arguments);
lexer.ReadToken();
break;
}
if (function != null)
{
result = Node.Function(function, new[] { result });
}
}
else
{
result = Node.Variable(name);
// We already read the next token, no need to do it here again...
}
break;
case TokenType.At:
lexer.ReadNode();
name = lexer.Content;
lexer.ReadToken();
if (lexer.Token != TokenType.LeftIndex)
{
throw new Exception("Invalid property identifier");
}
lexer.ReadNode();
result = Node.Property(name, lexer.Content);
lexer.ReadToken();
if (lexer.Token != TokenType.RightIndex)
{
throw new Exception("Invalid property identifier");
}
lexer.ReadToken();
break;
// There is no level below this, so let's throw an exception
default:
throw new Exception("Invalid value");
}
return(result);
}
private static Node ParseTerminal(Lexer lexer)
{
Node result;
switch (lexer.Type)
{
case TokenType.LeftParenthesis:
lexer.Next();
result = ParseConditional(lexer);
if (lexer.Type != TokenType.RightParenthesis)
{
throw new ParserException("Expected closing parenthesis, but found '{0}'".FormatString(lexer.Content));
}
lexer.Next();
break;
case TokenType.Number:
result = SpiceHelper.ParseNumber(lexer.Content);
lexer.Next();
break;
case TokenType.Identifier:
string name = lexer.Content;
lexer.Next();
if (lexer.Type == TokenType.LeftParenthesis)
{
// Function call!
lexer.Next();
string function = null;
switch (name.ToLowerInvariant())
{
case "vr":
function = "real";
goto case "v";
case "vi":
function = "imag";
goto case "v";
case "vm":
function = "abs";
goto case "v";
case "vdb":
function = "db";
goto case "v";
case "vp":
function = "arg";
goto case "v";
case "v":
// Read the nodes
lexer.ContinueWhileNode();
result = Node.Voltage(lexer.Content);
lexer.Next();
if (lexer.Type == TokenType.Comma)
{
lexer.Next(); lexer.ContinueWhileNode();
result = Node.Subtract(result, Node.Voltage(lexer.Content));
lexer.Next();
}
if (lexer.Type != TokenType.RightParenthesis)
{
throw new ParserException(lexer, "Expected closing parenthesis but found '{0}'".FormatString(lexer.Content));
}
lexer.Next();
break;
case "ir":
function = "real";
goto case "i";
case "ii":
function = "imag";
goto case "i";
case "im":
function = "abs";
goto case "i";
case "idb":
function = "db";
goto case "i";
case "ip":
function = "arg";
goto case "i";
case "i":
// Read the nodes
lexer.ContinueWhileNode();
result = Node.Current(lexer.Content);
lexer.Next();
if (lexer.Type != TokenType.RightParenthesis)
{
throw new ParserException("Expected closing parenthesis but found '{0}'".FormatString(lexer.Content));
}
lexer.Next();
break;
default:
var arguments = new List <Node>(2);
while (lexer.Type != TokenType.RightParenthesis)
{
arguments.Add(ParseConditional(lexer));
// continue
if (lexer.Type == TokenType.Comma)
{
lexer.Next();
}
else if (lexer.Type != TokenType.RightParenthesis)
{
throw new ParserException("Expected closing parenthesis but found '{0}'".FormatString(lexer.Content));
}
}
result = Node.Function(name, arguments);
lexer.Next();
break;
}
if (function != null)
{
Node.Function(function, new[] { result });
}
}
else
{
result = Node.Variable(name);
}
break;
case TokenType.At:
lexer.Next();
lexer.ContinueWhileNode();
name = lexer.Content;
lexer.Next();
if (lexer.Type != TokenType.LeftIndex)
{
throw new ParserException("Expected property indexing, but found '{0}'".FormatString(lexer.Content));
}
lexer.Next();
lexer.ContinueWhileNode();
result = Node.Property(name, lexer.Content);
if (lexer.Type != TokenType.RightIndex)
{
throw new ParserException("Expected closing indexer, but found '{0}'".FormatString(lexer.Content));
}
break;
default:
throw new ParserException("Invalid value");
}
return(result);
}
