public Expression<Func<Any>> Parse()
{
ahead = scanner.Scan();
if (ahead.Type == TokenType.Eof)
{
return null;
}
token = null;
var program = ProgramRule();
if (program == null)
{
ExpectError(ahead.Type);
}
while (TryExpect(TokenType.Eol))
{
}
Expect(TokenType.Eof);
//var folder = new ConstantFolder(runtime);
//result = folder.Modify(result);
return (Expression<Func<Any>>) program;
}
private void Get()
{
token = ahead;
ahead = scanner.Scan();
}
private void DoDedent(Token source)
{
levels.Pop();
var ded = new Token();
ded.Type = TokenType.Dedent;
ded.Col = source.Col;
ded.Line = source.Line;
pending.Enqueue(ded);
}
private void DoIndent(int level, Token source)
{
var s = source.Value;
if (s.Distinct().Count() > 1)
{
Console.WriteLine("Indent not same!");
throw new Exception();
}
if (it == 0)
{
it = s[0];
}
else if (it != s[0])
{
Console.WriteLine("Indent not same!");
throw new Exception();
}
levels.Push(level);
var ind = new Token();
ind.Type = TokenType.Indent;
ind.Col = source.Col;
ind.Line = source.Line;
pending.Enqueue(ind);
}
public Token Scan()
{
while (pending.Count == 0)
{
var token = Next();
if (token == error)
{
return null;
}
if (token == null)
{
token = Create(TokenType.Eof);
}
switch (token.Type)
{
case TokenType.Comment:
case TokenType.Ws:
break;
case TokenType.Eol:
{
var blankLine = last.Type == TokenType.Ws && last.Col == 1;
var commentLine = last.Type == TokenType.Comment && last.Col == 1;
if (token.Col > 1 && !blankLine && !commentLine && join == 0)
{
//Console.Write("[queued {0}]", token.Type);
pending.Enqueue(token);
}
}
break;
case TokenType.Eof:
{
if (last.Type != TokenType.Dummy && last.Type != TokenType.Eol)
{
var eol = Create(TokenType.Eol);
pending.Enqueue(eol);
}
while (levels.Peek() > 0) DoDedent(token);
pending.Enqueue(token);
}
break;
case TokenType.LParen:
case TokenType.LBrack:
++join;
pending.Enqueue(token);
break;
case TokenType.RParen:
case TokenType.RBrack:
--join;
pending.Enqueue(token);
break;
default:
{
if (last.Type == TokenType.Eol)
{
while (levels.Peek() > 0) DoDedent(token);
}
else if (last.Type == TokenType.Ws)
{
if (last.Col == 1 && join == 0)
{
var level = last.Length;
var curLevel = levels.Peek();
if (level > curLevel)
{
DoIndent(level, last);
}
else if (level < curLevel)
{
do
{
DoDedent(token);
}
while (level < levels.Peek());
}
}
}
pending.Enqueue(token);
}
break;
}
last = token;
}
return pending.Dequeue();
}
public Scanner(string data)
{
this.data = data;
col = 1;
line = 1;
p = 0;
pe = data.Length;
eof = data.Length;
it = (char)0;
levels = new Stack<int>();
pending = new Queue<Token>();
finished = false;
join = 0;
last = Create(TokenType.Dummy);
error = Create(TokenType.Dummy);
#line 472 "Scanner.cs"
{
cs = scan_start;
ts = -1;
te = -1;
act = 0;
}
#line 416 "Scanner.rl"
levels.Push(0);
}
private Token Create(TokenType type)
{
var token = new Token();
token.Type = type;
token.Col = col;
token.Line = line;
switch (type)
{
case TokenType.Dummy:
case TokenType.Indent:
case TokenType.Dedent:
case TokenType.Eof:
token.Length = -1;
token.Size = -1;
break;
case TokenType.Ws:
{
token.Value = GetTokenString(ts, te);
token.Length = token.Value.Length;
var width = 4;
foreach (var c in token.Value)
{
switch (c)
{
case ' ':
col++;
break;
case '\t':
col = ((col + width) & ~(width - 1)) + 1;
break;
}
}
break;
}
case TokenType.Eol:
col = 1;
line++;
break;
case TokenType.String:
token.Value = GetTokenString(ts, te);
token.Length = token.Value.Length;
for (var i = ts; i != te; i++)
{
switch (data[i])
{
case '\r':
col = 1;
line++;
if (data[i + 1] == '\n') i++;
break;
case '\n':
col = 1;
line++;
break;
default:
col++;
break;
}
}
break;
default:
token.Value = GetTokenString(ts, te);
token.Length = token.Value.Length;
col += token.Length;
break;
}
return token;
}
