public static MalVal read_atom(Reader rdr)
{
string token = rdr.next();
string pattern = @"(^-?[0-9]+$)|(^-?[0-9][0-9.]*$)|(^nil$)|(^true$)|(^false$)|^("".*)|:(.*)|(^[^""]*$)";
Regex regex = new Regex(pattern);
Match match = regex.Match(token);
//Console.WriteLine("token: ^" + token + "$");
if (!match.Success)
{
throw new ParseError("unrecognized token '" + token + "'");
}
if (match.Groups[1].Value != String.Empty)
{
return(new Mal.types.MalInt(int.Parse(match.Groups[1].Value)));
}
else if (match.Groups[3].Value != String.Empty)
{
return(Mal.types.Nil);
}
else if (match.Groups[4].Value != String.Empty)
{
return(Mal.types.True);
}
else if (match.Groups[5].Value != String.Empty)
{
return(Mal.types.False);
}
else if (match.Groups[6].Value != String.Empty)
{
string str = match.Groups[6].Value;
if (str[str.Length - 1] != '"')
{
throw new ParseError("expected '\"', got EOF");
}
str = str.Substring(1, str.Length - 2)
.Replace("\\\\", "\u029e")
.Replace("\\\"", "\"")
.Replace("\\n", "\n")
.Replace("\u029e", "\\");
return(new Mal.types.MalString(str));
}
else if (match.Groups[7].Value != String.Empty)
{
return(new Mal.types.MalString("\u029e" + match.Groups[7].Value));
}
else if (match.Groups[8].Value != String.Empty)
{
return(new Mal.types.MalSymbol(match.Groups[8].Value));
}
else
{
throw new ParseError("unrecognized '" + match.Groups[0] + "'");
}
}
public static MalVal read_list(Reader rdr, MalList lst, char start, char end)
{
string token = rdr.next();
if (token[0] != start)
{
throw new ParseError("expected '" + start + "'");
}
while ((token = rdr.peek()) != null && token[0] != end)
{
lst.conj_BANG(read_form(rdr));
}
if (token == null)
{
throw new ParseError("expected '" + end + "', got EOF");
}
rdr.next();
return(lst);
}
public static MalVal read_form(Reader rdr)
{
string token = rdr.peek();
if (token == null)
{
throw new MalContinue();
}
MalVal form = null;
switch (token)
{
case "'": rdr.next();
return(new MalList(new MalSymbol("quote"),
read_form(rdr)));
case "`": rdr.next();
return(new MalList(new MalSymbol("quasiquote"),
read_form(rdr)));
case "~":
rdr.next();
return(new MalList(new MalSymbol("unquote"),
read_form(rdr)));
case "~@":
rdr.next();
return(new MalList(new MalSymbol("splice-unquote"),
read_form(rdr)));
case "^": rdr.next();
MalVal meta = read_form(rdr);
return(new MalList(new MalSymbol("with-meta"),
read_form(rdr),
meta));
case "@": rdr.next();
return(new MalList(new MalSymbol("deref"),
read_form(rdr)));
case "(": form = read_list(rdr, new MalList(), '(', ')'); break;
case ")": throw new ParseError("unexpected ')'");
case "[": form = read_list(rdr, new MalVector(), '[', ']'); break;
case "]": throw new ParseError("unexpected ']'");
case "{": form = read_hash_map(rdr); break;
case "}": throw new ParseError("unexpected '}'");
default: form = read_atom(rdr); break;
}
return(form);
}
