public override string ToString()
{
var builder = new StringBuilder();
builder.Append(Identifier.ToString());
builder.Append(LeftParen.ToString());
builder.Append(Parameters.ToString());
builder.Append(RightParen.ToString());
return(builder.ToString());
}
private static NextToken ReadToken(this IEnumerable <CodeCharacter> code)
{
code = code.SkipWhile(c => c.IsWhitespace);
if (!code.Any())
{
var token = new EndOfFile();
return(new NextToken(token, () => ReadToken(code)));
}
var firstTokenChar = code.First();
if (firstTokenChar.IsStartOfIdentifier)
{
var identifier = code
.TakeWhile(c => c.IsBodyOfIdentifier)
.Aggregate("", (s, c) => s + c.Value);
code = code.SkipWhile(c => c.IsBodyOfIdentifier);
var token = KeywordTable.ContainsKey(identifier)
? KeywordTable[identifier].Invoke() as Token
: new Identifier();
token.Value = identifier;
token.LineNumber = firstTokenChar.LineNumber;
token.LinePosition = firstTokenChar.LinePosition;
return(new NextToken(token, () => ReadToken(code)));
}
if (firstTokenChar.IsDigit)
{
var number = code
.TakeWhile(c => c.IsDigit)
.Aggregate("", (s, c) => s + c.Value);
code = code.Skip(number.Length);
var token = new IntegerConstant();
token.Value = number;
token.LineNumber = firstTokenChar.LineNumber;
token.LinePosition = firstTokenChar.LinePosition;
return(new NextToken(token, () => ReadToken(code)));
}
if (firstTokenChar.IsStartOfStringLiteral)
{
var stringLiteral = code
.Skip(1)
.TakeWhile(c => c.Value != '"')
.Aggregate("\"", (s, c) => s + c.Value)
+ '"';
Debug.WriteLine(stringLiteral);
code = code.Skip(stringLiteral.Length);
var token = new StringLiteral();
token.Value = stringLiteral;
token.LineNumber = firstTokenChar.LineNumber;
token.LinePosition = firstTokenChar.LinePosition;
return(new NextToken(token, () => ReadToken(code)));
}
var t = new InvalidToken() as Token;
switch (firstTokenChar.Value)
{
case '(': t = new LeftParen(); break;
case ')': t = new RightParen(); break;
case '{': t = new LeftCurlyBrace(); break;
case '}': t = new RightCurlyBrace(); break;
case '[': t = new LeftSquareBracket(); break;
case ']': t = new RightSquareBracket(); break;
case ',': t = new Comma(); break;
case '*': t = new Asterisk(); break;
case ';': t = new Semicolon(); break;
}
code = code.Skip(1);
t.Value = firstTokenChar.Value.ToString();
t.LineNumber = firstTokenChar.LineNumber;
t.LinePosition = firstTokenChar.LinePosition;
return(new NextToken(t, () => ReadToken(code)));
}
