public WSOperation(string _name, OperatorChars _operatorChar, List <string> _aliaces = null) : base(_name, _aliaces)
{
OperatorChar = Operators[_operatorChar];
}
public WSStateOperation(string _name, OperatorChars _operatorChar, List <string> _aliaces = null) : base(_name, _operatorChar, _aliaces)
{
}
/// <summary>
/// Scans a token.
/// </summary>
void ScanToken()
{
var c = source.Peek();
// Test for whitespace
if (char.IsWhiteSpace(source.Peek()))
{
// Skip the whitespace
source.SkipWhitespace();
return;
}
// Test for hexadecimal number
if (source.See(2) && source.Peeks(2) == "0x")
{
// Read a hexadecimal number
ReadHexNumber();
return;
}
// Test for decimal number
if (char.IsDigit(c))
{
// Read a decimal number
ReadNumber();
return;
}
// Test for single-character operator
if (OperatorChars.Contains(c.ToString()))
{
// Read an operator
ReadOperator();
return;
}
// Build key-value-pairs of characters and their
// corresponding token classes.
var dict = new Dictionary <char, TokenClass> {
{ '{', TokenClass.OpenBrace },
{ '}', TokenClass.CloseBrace },
{ '(', TokenClass.OpenParen },
{ ')', TokenClass.CloseParen },
{ '[', TokenClass.OpenBracket },
{ ']', TokenClass.CloseBracket },
{ ';', TokenClass.Semicolon },
{ ':', TokenClass.Colon },
{ ',', TokenClass.Comma }
};
// Test for those characters
if (dict.ContainsKey(c))
{
// Skip if advancing is possible
if (source.See())
{
source.Skip();
}
// Add the lexeme
lexemes.Add(new Lexeme(dict[c], source, c));
return;
}
// Test for other stuff
switch (c)
{
case '#':
// Skip a character
source.Skip();
// Read a comment line
var comment = source.ReadLine();
// Test if the line cotnains source analysis hints
if (comment.TrimStart().StartsWith("analysis", StringComparison.Ordinal))
{
// Parse the source analysis hint
var parts = comment.Trim().Split(' ');
if (parts.Length != 3)
{
break;
}
var action = parts[1].Trim();
var name = parts[2].Trim();
// Add the source analysis hint
lexemes.Add(new Lexeme(TokenClass.SourceAnalysisHint, source, $"{action}:{name}"));
}
break;
case '\'':
case '"':
case '`':
// Read a string
ReadString();
break;
default:
// Test for binary string
if (source.See() && c == 'b' && (source.Peek(1) == '\"' || source.Peek(1) == '\''))
{
// Read a binary string
ReadBinaryString();
break;
}
// Test for identifier
if (char.IsLetter(c) || c == '_')
{
// Read an identifier
ReadIdentifier();
break;
}
// The token was not handled by any of the above code; Throw an exception
throw new Exception($"Unexpected token: '{c}' at {source.Location}.");
}
}
