This commit was manufactured by cvs2svn to create branch 'mono-1-0'.
[mono.git] / mcs / gmcs / cs-tokenizer.cs
index 93f0a2549372e53e6723bf2b703f760437829377..0fdc84b6ce5fe49dc9c9f9832b9d4ac230b0fd3b 100755 (executable)
@@ -1,3 +1,4 @@
+// -*- coding: dos -*-\r
 //\r
 // cs-tokenizer.cs: The Tokenizer for the C# compiler\r
 //                  This also implements the preprocessor\r
@@ -147,7 +148,7 @@ namespace Mono.CSharp
                //\r
                // Class variables\r
                // \r
-               static Hashtable keywords;\r
+               static CharArrayHashtable[] keywords;\r
                static NumberStyles styles;\r
                static NumberFormatInfo csharp_format_info;\r
                \r
@@ -178,6 +179,8 @@ namespace Mono.CSharp
                const int max_id_size = 512;\r
                static char [] id_builder = new char [max_id_size];\r
 \r
+               static CharArrayHashtable [] identifiers = new CharArrayHashtable [max_id_size + 1];\r
+\r
                const int max_number_size = 128;\r
                static char [] number_builder = new char [max_number_size];\r
                static int number_pos;\r
@@ -205,98 +208,101 @@ namespace Mono.CSharp
                        }\r
                }\r
 \r
+               static void AddKeyword (string kw, int token) {\r
+                       if (keywords [kw.Length] == null) {\r
+                               keywords [kw.Length] = new CharArrayHashtable (kw.Length);\r
+                       }\r
+                       keywords [kw.Length] [kw.ToCharArray ()] = token;\r
+               }\r
+\r
                static void InitTokens ()\r
                {\r
-                       keywords = new Hashtable ();\r
-\r
-                       keywords.Add ("abstract", Token.ABSTRACT);\r
-                       keywords.Add ("as", Token.AS);\r
-                       keywords.Add ("add", Token.ADD);\r
-                       keywords.Add ("assembly", Token.ASSEMBLY);\r
-                       keywords.Add ("base", Token.BASE);\r
-                       keywords.Add ("bool", Token.BOOL);\r
-                       keywords.Add ("break", Token.BREAK);\r
-                       keywords.Add ("byte", Token.BYTE);\r
-                       keywords.Add ("case", Token.CASE);\r
-                       keywords.Add ("catch", Token.CATCH);\r
-                       keywords.Add ("char", Token.CHAR);\r
-                       keywords.Add ("checked", Token.CHECKED);\r
-                       keywords.Add ("class", Token.CLASS);\r
-                       keywords.Add ("const", Token.CONST);\r
-                       keywords.Add ("continue", Token.CONTINUE);\r
-                       keywords.Add ("decimal", Token.DECIMAL);\r
-                       keywords.Add ("default", Token.DEFAULT);\r
-                       keywords.Add ("delegate", Token.DELEGATE);\r
-                       keywords.Add ("do", Token.DO);\r
-                       keywords.Add ("double", Token.DOUBLE);\r
-                       keywords.Add ("else", Token.ELSE);\r
-                       keywords.Add ("enum", Token.ENUM);\r
-                       keywords.Add ("event", Token.EVENT);\r
-                       keywords.Add ("explicit", Token.EXPLICIT);\r
-                       keywords.Add ("extern", Token.EXTERN);\r
-                       keywords.Add ("false", Token.FALSE);\r
-                       keywords.Add ("finally", Token.FINALLY);\r
-                       keywords.Add ("fixed", Token.FIXED);\r
-                       keywords.Add ("float", Token.FLOAT);\r
-                       keywords.Add ("for", Token.FOR);\r
-                       keywords.Add ("foreach", Token.FOREACH);\r
-                       keywords.Add ("goto", Token.GOTO);\r
-                       keywords.Add ("get", Token.GET);\r
-                       keywords.Add ("if", Token.IF);\r
-                       keywords.Add ("implicit", Token.IMPLICIT);\r
-                       keywords.Add ("in", Token.IN);\r
-                       keywords.Add ("int", Token.INT);\r
-                       keywords.Add ("interface", Token.INTERFACE);\r
-                       keywords.Add ("internal", Token.INTERNAL);\r
-                       keywords.Add ("is", Token.IS);\r
-                       keywords.Add ("lock", Token.LOCK);\r
-                       keywords.Add ("long", Token.LONG);\r
-                       keywords.Add ("namespace", Token.NAMESPACE);\r
-                       keywords.Add ("new", Token.NEW);\r
-                       keywords.Add ("null", Token.NULL);\r
-                       keywords.Add ("object", Token.OBJECT);\r
-                       keywords.Add ("operator", Token.OPERATOR);\r
-                       keywords.Add ("out", Token.OUT);\r
-                       keywords.Add ("override", Token.OVERRIDE);\r
-                       keywords.Add ("params", Token.PARAMS);\r
-                       keywords.Add ("private", Token.PRIVATE);\r
-                       keywords.Add ("protected", Token.PROTECTED);\r
-                       keywords.Add ("public", Token.PUBLIC);\r
-                       keywords.Add ("readonly", Token.READONLY);\r
-                       keywords.Add ("ref", Token.REF);\r
-                       keywords.Add ("remove", Token.REMOVE);\r
-                       keywords.Add ("return", Token.RETURN);\r
-                       keywords.Add ("sbyte", Token.SBYTE);\r
-                       keywords.Add ("sealed", Token.SEALED);\r
-                       keywords.Add ("set", Token.SET);\r
-                       keywords.Add ("short", Token.SHORT);\r
-                       keywords.Add ("sizeof", Token.SIZEOF);\r
-                       keywords.Add ("stackalloc", Token.STACKALLOC);\r
-                       keywords.Add ("static", Token.STATIC);\r
-                       keywords.Add ("string", Token.STRING);\r
-                       keywords.Add ("struct", Token.STRUCT);\r
-                       keywords.Add ("switch", Token.SWITCH);\r
-                       keywords.Add ("this", Token.THIS);\r
-                       keywords.Add ("throw", Token.THROW);\r
-                       keywords.Add ("true", Token.TRUE);\r
-                       keywords.Add ("try", Token.TRY);\r
-                       keywords.Add ("typeof", Token.TYPEOF);\r
-                       keywords.Add ("uint", Token.UINT);\r
-                       keywords.Add ("ulong", Token.ULONG);\r
-                       keywords.Add ("unchecked", Token.UNCHECKED);\r
-                       keywords.Add ("unsafe", Token.UNSAFE);\r
-                       keywords.Add ("ushort", Token.USHORT);\r
-                       keywords.Add ("using", Token.USING);\r
-                       keywords.Add ("virtual", Token.VIRTUAL);\r
-                       keywords.Add ("void", Token.VOID);\r
-                       keywords.Add ("volatile", Token.VOLATILE);\r
-                       keywords.Add ("where", Token.WHERE);\r
-                       keywords.Add ("while", Token.WHILE);\r
-\r
-                       if (RootContext.V2){\r
-                               keywords.Add ("__yield", Token.YIELD);\r
-                               keywords.Add ("yield", Token.YIELD);\r
-                       }\r
+                       keywords = new CharArrayHashtable [64];\r
+\r
+                       AddKeyword ("__arglist", Token.ARGLIST);\r
+                       AddKeyword ("abstract", Token.ABSTRACT);\r
+                       AddKeyword ("as", Token.AS);\r
+                       AddKeyword ("add", Token.ADD);\r
+                       AddKeyword ("assembly", Token.ASSEMBLY);\r
+                       AddKeyword ("base", Token.BASE);\r
+                       AddKeyword ("bool", Token.BOOL);\r
+                       AddKeyword ("break", Token.BREAK);\r
+                       AddKeyword ("byte", Token.BYTE);\r
+                       AddKeyword ("case", Token.CASE);\r
+                       AddKeyword ("catch", Token.CATCH);\r
+                       AddKeyword ("char", Token.CHAR);\r
+                       AddKeyword ("checked", Token.CHECKED);\r
+                       AddKeyword ("class", Token.CLASS);\r
+                       AddKeyword ("const", Token.CONST);\r
+                       AddKeyword ("continue", Token.CONTINUE);\r
+                       AddKeyword ("decimal", Token.DECIMAL);\r
+                       AddKeyword ("default", Token.DEFAULT);\r
+                       AddKeyword ("delegate", Token.DELEGATE);\r
+                       AddKeyword ("do", Token.DO);\r
+                       AddKeyword ("double", Token.DOUBLE);\r
+                       AddKeyword ("else", Token.ELSE);\r
+                       AddKeyword ("enum", Token.ENUM);\r
+                       AddKeyword ("event", Token.EVENT);\r
+                       AddKeyword ("explicit", Token.EXPLICIT);\r
+                       AddKeyword ("extern", Token.EXTERN);\r
+                       AddKeyword ("false", Token.FALSE);\r
+                       AddKeyword ("finally", Token.FINALLY);\r
+                       AddKeyword ("fixed", Token.FIXED);\r
+                       AddKeyword ("float", Token.FLOAT);\r
+                       AddKeyword ("for", Token.FOR);\r
+                       AddKeyword ("foreach", Token.FOREACH);\r
+                       AddKeyword ("goto", Token.GOTO);\r
+                       AddKeyword ("get", Token.GET);\r
+                       AddKeyword ("if", Token.IF);\r
+                       AddKeyword ("implicit", Token.IMPLICIT);\r
+                       AddKeyword ("in", Token.IN);\r
+                       AddKeyword ("int", Token.INT);\r
+                       AddKeyword ("interface", Token.INTERFACE);\r
+                       AddKeyword ("internal", Token.INTERNAL);\r
+                       AddKeyword ("is", Token.IS);\r
+                       AddKeyword ("lock", Token.LOCK);\r
+                       AddKeyword ("long", Token.LONG);\r
+                       AddKeyword ("namespace", Token.NAMESPACE);\r
+                       AddKeyword ("new", Token.NEW);\r
+                       AddKeyword ("null", Token.NULL);\r
+                       AddKeyword ("object", Token.OBJECT);\r
+                       AddKeyword ("operator", Token.OPERATOR);\r
+                       AddKeyword ("out", Token.OUT);\r
+                       AddKeyword ("override", Token.OVERRIDE);\r
+                       AddKeyword ("params", Token.PARAMS);\r
+                       AddKeyword ("private", Token.PRIVATE);\r
+                       AddKeyword ("protected", Token.PROTECTED);\r
+                       AddKeyword ("public", Token.PUBLIC);\r
+                       AddKeyword ("readonly", Token.READONLY);\r
+                       AddKeyword ("ref", Token.REF);\r
+                       AddKeyword ("remove", Token.REMOVE);\r
+                       AddKeyword ("return", Token.RETURN);\r
+                       AddKeyword ("sbyte", Token.SBYTE);\r
+                       AddKeyword ("sealed", Token.SEALED);\r
+                       AddKeyword ("set", Token.SET);\r
+                       AddKeyword ("short", Token.SHORT);\r
+                       AddKeyword ("sizeof", Token.SIZEOF);\r
+                       AddKeyword ("stackalloc", Token.STACKALLOC);\r
+                       AddKeyword ("static", Token.STATIC);\r
+                       AddKeyword ("string", Token.STRING);\r
+                       AddKeyword ("struct", Token.STRUCT);\r
+                       AddKeyword ("switch", Token.SWITCH);\r
+                       AddKeyword ("this", Token.THIS);\r
+                       AddKeyword ("throw", Token.THROW);\r
+                       AddKeyword ("true", Token.TRUE);\r
+                       AddKeyword ("try", Token.TRY);\r
+                       AddKeyword ("typeof", Token.TYPEOF);\r
+                       AddKeyword ("uint", Token.UINT);\r
+                       AddKeyword ("ulong", Token.ULONG);\r
+                       AddKeyword ("unchecked", Token.UNCHECKED);\r
+                       AddKeyword ("unsafe", Token.UNSAFE);\r
+                       AddKeyword ("ushort", Token.USHORT);\r
+                       AddKeyword ("using", Token.USING);\r
+                       AddKeyword ("virtual", Token.VIRTUAL);\r
+                       AddKeyword ("void", Token.VOID);\r
+                       AddKeyword ("volatile", Token.VOLATILE);\r
+                       AddKeyword ("where", Token.WHERE);\r
+                       AddKeyword ("while", Token.WHILE);\r
                }\r
 \r
                //\r
@@ -311,9 +317,16 @@ namespace Mono.CSharp
                        string_builder = new System.Text.StringBuilder ();\r
                }\r
 \r
-               int GetKeyword (string name)\r
+               int GetKeyword (char[] id, int id_len)\r
                {\r
-                       object o = keywords [name];\r
+                       /*\r
+                        * Keywords are stored in an array of hashtables grouped by their\r
+                        * length.\r
+                        */\r
+\r
+                       if ((id_len >= keywords.Length) || (keywords [id_len] == null))\r
+                               return -1;\r
+                       object o = keywords [id_len] [id];\r
 \r
                        if (o == null)\r
                                return -1;\r
@@ -369,14 +382,33 @@ namespace Mono.CSharp
                        Mono.CSharp.Location.Push (file);\r
                }\r
 \r
-               bool is_identifier_start_character (char c)\r
+               public static void Cleanup () {\r
+                       identifiers = null;\r
+               }\r
+\r
+               static bool is_identifier_start_character (char c)\r
                {\r
                        return (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') || c == '_' || Char.IsLetter (c);\r
                }\r
 \r
-               bool is_identifier_part_character (char c)\r
+               static bool is_identifier_part_character (char c)\r
                {\r
                        return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || c == '_' || (c >= '0' && c <= '9') || Char.IsLetter (c);\r
+               }
+               
+               public static bool IsValidIdentifier (string s)
+               {
+                       if (s == null || s.Length == 0)
+                               return false;
+                       
+                       if (!is_identifier_start_character (s [0]))
+                               return false;
+                       
+                       for (int i = 1; i < s.Length; i ++)
+                               if (! is_identifier_part_character (s [i]))
+                                       return false;
+                       
+                       return true;
                }\r
 \r
                bool parse_less_than ()\r
@@ -411,7 +443,7 @@ namespace Mono.CSharp
 \r
                        if (the_token == Token.OP_GENERICS_GT)\r
                                return true;\r
-                       else if (the_token == Token.COMMA)\r
+                       else if ((the_token == Token.COMMA) || (the_token == Token.DOT))\r
                                goto start;\r
                        else if (the_token == Token.OP_GENERICS_LT) {\r
                                if (!parse_less_than ())\r
@@ -626,37 +658,6 @@ namespace Mono.CSharp
                                return Token.CARRET;\r
                        }\r
 \r
-#if FIXME\r
-                       if (c == '>'){\r
-                               if (deambiguate_greater_than == 0)\r
-                                       return Token.OP_GT;\r
-\r
-                               --deambiguate_greater_than;\r
-\r
-                               // Save current position and parse next token.\r
-                               int old = reader.Position;\r
-                               int new_token = token ();\r
-                               reader.Position = old;\r
-                               putback_char = -1;\r
-\r
-                               switch (new_token) {\r
-                               case Token.OPEN_PARENS:\r
-                               case Token.CLOSE_PARENS:\r
-                               case Token.CLOSE_BRACKET:\r
-                               case Token.OP_GT:\r
-                               case Token.COLON:\r
-                               case Token.SEMICOLON:\r
-                               case Token.COMMA:\r
-                               case Token.DOT:\r
-                               case Token.INTERR:\r
-                                       return Token.OP_GENERICS_GT;\r
-\r
-                               default:\r
-                                       return Token.OP_GT;\r
-                               }\r
-                       }\r
-#endif\r
-\r
                        return Token.ERROR;\r
                }\r
 \r
@@ -891,10 +892,6 @@ namespace Mono.CSharp
                        getChar ();\r
                        while ((d = peekChar ()) != -1){\r
                                if (is_hex (d)){\r
-                                       if (number_pos == 16){\r
-                                               Report.Error (1021, Location, "Integral constant too large");\r
-                                               return Token.ERROR;\r
-                                       }\r
                                        number_builder [number_pos++] = (char) d;\r
                                        getChar ();\r
                                } else\r
@@ -902,10 +899,18 @@ namespace Mono.CSharp
                        }\r
                        \r
                        string s = new String (number_builder, 0, number_pos);\r
-                       if (number_pos <= 8)\r
-                               ul = System.UInt32.Parse (s, NumberStyles.HexNumber);\r
-                       else\r
-                               ul = System.UInt64.Parse (s, NumberStyles.HexNumber);\r
+                       try {\r
+                               if (number_pos <= 8)\r
+                                       ul = System.UInt32.Parse (s, NumberStyles.HexNumber);\r
+                               else\r
+                                       ul = System.UInt64.Parse (s, NumberStyles.HexNumber);\r
+                       } catch (OverflowException){\r
+                               error_details = "Integral constant is too large";\r
+                               Report.Error (1021, Location, error_details);\r
+                               val = 0ul;\r
+                               return Token.LITERAL_INTEGER;\r
+                       }\r
+                       \r
                        return integer_type_suffix (ul, peekChar ());\r
                }\r
 \r
@@ -995,7 +1000,6 @@ namespace Mono.CSharp
                //\r
                int getHex (int count, out bool error)\r
                {\r
-                       int [] buffer = new int [8];\r
                        int i;\r
                        int total = 0;\r
                        int c;\r
@@ -1164,6 +1168,19 @@ namespace Mono.CSharp
                        case Token.TYPEOF:\r
                        case Token.UNCHECKED:\r
                        case Token.UNSAFE:\r
+\r
+                               //\r
+                               // These can be part of a member access\r
+                               //\r
+                       case Token.INT:\r
+                       case Token.UINT:\r
+                       case Token.SHORT:\r
+                       case Token.USHORT:\r
+                       case Token.LONG:\r
+                       case Token.ULONG:\r
+                       case Token.DOUBLE:\r
+                       case Token.FLOAT:\r
+                       case Token.CHAR:\r
                                return true;\r
 \r
                        default:\r
@@ -1174,7 +1191,19 @@ namespace Mono.CSharp
                public int token ()\r
                 {\r
                        current_token = xtoken ();\r
-                        return current_token;\r
+\r
+                       if (current_token != Token.DEFAULT)\r
+                               return current_token;\r
+\r
+                       int c = consume_whitespace ();\r
+                       if (c == -1)\r
+                               current_token = Token.ERROR;\r
+                       else if (c == '(')\r
+                               current_token = Token.DEFAULT_OPEN_PARENS;\r
+                       else\r
+                               putback (c);\r
+\r
+                       return current_token;\r
                 }\r
 \r
                static StringBuilder static_cmd_arg = new System.Text.StringBuilder ();\r
@@ -1186,9 +1215,19 @@ namespace Mono.CSharp
                        tokens_seen = false;\r
                        arg = "";\r
                        static_cmd_arg.Length = 0;\r
+\r
+                       // skip over white space\r
+                       while ((c = getChar ()) != -1 && (c != '\n') && ((c == '\r') || (c == ' ') || (c == '\t')))\r
+                               ;\r
                                \r
-                       while ((c = getChar ()) != -1 && (c != '\n') && (c != ' ') && (c != '\t') && (c != '\r')){\r
-                               static_cmd_arg.Append ((char) c);\r
+                       while ((c != -1) && (c != '\n') && (c != ' ') && (c != '\t') && (c != '\r')){\r
+                               if (is_identifier_part_character ((char) c)){\r
+                                       static_cmd_arg.Append ((char) c);\r
+                                       c = getChar ();\r
+                               } else {\r
+                                       putback (c);\r
+                                       break;\r
+                               }\r
                        }\r
 \r
                        cmd = static_cmd_arg.ToString ();\r
@@ -1241,6 +1280,11 @@ namespace Mono.CSharp
                                ref_name = file_name;\r
                                Location.Push (ref_name);\r
                                return true;\r
+                       } else if (arg == "hidden"){\r
+                               //\r
+                               // We ignore #line hidden\r
+                               //\r
+                               return true;\r
                        }\r
                        \r
                        try {\r
@@ -1254,6 +1298,8 @@ namespace Mono.CSharp
                                        \r
                                        string name = arg.Substring (pos). Trim (quotes);\r
                                        ref_name = Location.LookupFile (name);\r
+                                       file_name.HasLineDirective = true;\r
+                                       ref_name.HasLineDirective = true;\r
                                        Location.Push (ref_name);\r
                                } else {\r
                                        ref_line = System.Int32.Parse (arg);\r
@@ -1491,7 +1537,6 @@ namespace Mono.CSharp
                //\r
                bool handle_preprocessing_directive (bool caller_is_taking)\r
                {\r
-                       char [] blank = { ' ', '\t' };\r
                        string cmd, arg;\r
                        bool region_directive = false;\r
 \r
@@ -1746,25 +1791,41 @@ namespace Mono.CSharp
                                }\r
                        }\r
 \r
-                       string ids = new String (id_builder, 0, pos);\r
-\r
                        //\r
                        // Optimization: avoids doing the keyword lookup\r
                        // on uppercase letters and _\r
                        //\r
-                       if (s >= 'a'){\r
-                               int keyword = GetKeyword (ids);\r
-                               if (keyword == -1 || quoted){\r
-                                       val = ids;\r
+                       if (s >= 'a' || s == '_'){\r
+                               int keyword = GetKeyword (id_builder, pos);\r
+                               if (keyword != -1 && !quoted)\r
+                               return keyword;\r
+                       }\r
+\r
+                       //\r
+                       // Keep identifiers in an array of hashtables to avoid needless\r
+                       // allocations\r
+                       //\r
+\r
+                       if (identifiers [pos] != null) {\r
+                               val = identifiers [pos][id_builder];\r
+                               if (val != null) {\r
                                        return Token.IDENTIFIER;\r
                                }\r
-                               return keyword;\r
                        }\r
-                       val = ids;\r
+                       else\r
+                               identifiers [pos] = new CharArrayHashtable (pos);\r
+\r
+                       val = new String (id_builder, 0, pos);\r
+\r
+                       char [] chars = new char [pos];\r
+                       Array.Copy (id_builder, chars, pos);\r
+\r
+                       identifiers [pos] [chars] = val;\r
+\r
                        return Token.IDENTIFIER;\r
                }\r
-               \r
-               public int xtoken ()\r
+\r
+               int consume_whitespace ()\r
                {\r
                        int t;\r
                        bool doread = false;\r
@@ -1773,10 +1834,26 @@ namespace Mono.CSharp
                        val = null;\r
                        // optimization: eliminate col and implement #directive semantic correctly.\r
                        for (;(c = getChar ()) != -1; col++) {\r
-                               if (c == ' ' || c == '\t' || c == '\f' || c == '\v' || c == '\r' || c == 0xa0){\r
-                                       \r
-                                       if (c == '\t')\r
-                                               col = (((col + 8) / 8) * 8) - 1;\r
+                               if (c == ' ')\r
+                                       continue;\r
+                               \r
+                               if (c == '\t') {\r
+                                       col = (((col + 8) / 8) * 8) - 1;\r
+                                       continue;\r
+                               }\r
+                               \r
+                               if (c == ' ' || c == '\f' || c == '\v' || c == 0xa0)\r
+                                       continue;\r
+\r
+                               if (c == '\r') {\r
+                                       if (peekChar () == '\n')\r
+                                               getChar ();\r
+\r
+                                       line++;\r
+                                       ref_line++;\r
+                                       col = 0;\r
+                                       any_token_seen |= tokens_seen;\r
+                                       tokens_seen = false;\r
                                        continue;\r
                                }\r
 \r
@@ -1818,22 +1895,7 @@ namespace Mono.CSharp
                                        goto is_punct_label;\r
                                }\r
 \r
-                               \r
-                               if (is_identifier_start_character ((char)c)){\r
-                                       tokens_seen = true;\r
-                                       return consume_identifier (c, false);\r
-                               }\r
-\r
                        is_punct_label:\r
-                               if ((t = is_punct ((char)c, ref doread)) != Token.ERROR){\r
-                                       tokens_seen = true;\r
-                                       if (doread){\r
-                                               getChar ();\r
-                                               col++;\r
-                                       }\r
-                                       return t;\r
-                               }\r
-\r
                                // white space\r
                                if (c == '\n'){\r
                                        line++;\r
@@ -1844,19 +1906,6 @@ namespace Mono.CSharp
                                        continue;\r
                                }\r
 \r
-                               if (c >= '0' && c <= '9'){\r
-                                       tokens_seen = true;\r
-                                       return is_number (c);\r
-                               }\r
-\r
-                               if (c == '.'){\r
-                                       tokens_seen = true;\r
-                                       int peek = peekChar ();\r
-                                       if (peek >= '0' && peek <= '9')\r
-                                               return is_number (c);\r
-                                       return Token.DOT;\r
-                               }\r
-                               \r
                                /* For now, ignore pre-processor commands */\r
                                // FIXME: In C# the '#' is not limited to appear\r
                                // on the first column.\r
@@ -1893,72 +1942,115 @@ namespace Mono.CSharp
                                                Report.Error (1027, Location, "#endif/#endregion expected");\r
                                        continue;\r
                                }\r
-                               \r
-                               if (c == '"') \r
-                                       return consume_string (false);\r
 \r
-                               if (c == '\''){\r
-                                       c = getChar ();\r
-                                       tokens_seen = true;\r
-                                       if (c == '\''){\r
-                                               error_details = "Empty character literal";\r
-                                               Report.Error (1011, Location, error_details);\r
-                                               return Token.ERROR;\r
-                                       }\r
-                                       c = escape (c);\r
-                                       if (c == -1)\r
-                                               return Token.ERROR;\r
-                                       val = new System.Char ();\r
-                                       val = (char) c;\r
-                                       c = getChar ();\r
+                               return c;\r
+                       }\r
 \r
-                                       if (c != '\''){\r
-                                               error_details = "Too many characters in character literal";\r
-                                               Report.Error (1012, Location, error_details);\r
+                       return -1;\r
+               }\r
+               \r
+               public int xtoken ()\r
+               {\r
+                       int t;\r
+                       bool doread = false;\r
+                       int c;\r
 \r
-                                               // Try to recover, read until newline or next "'"\r
-                                               while ((c = getChar ()) != -1){\r
-                                                       if (c == '\n' || c == '\''){\r
-                                                               line++;\r
-                                                               ref_line++;\r
-                                                               col = 0;\r
-                                                               break;\r
-                                                       } else\r
-                                                               col++;\r
-                                                       \r
-                                               }\r
-                                               return Token.ERROR;\r
-                                       }\r
-                                       return Token.LITERAL_CHARACTER;\r
-                               }\r
-                               \r
-                               if (c == '@') {\r
-                                       c = getChar ();\r
-                                       if (c == '"') {\r
-                                               tokens_seen = true;\r
-                                               return consume_string (true);\r
-                                       } else if (is_identifier_start_character ((char) c)){\r
-                                               return consume_identifier (c, true);\r
-                                       } else {\r
-                                               Report.Error (1033, Location, "'@' must be followed by string constant or identifier");\r
-                                       }\r
+                       val = null;\r
+                       // optimization: eliminate col and implement #directive semantic correctly.\r
+\r
+                       c = consume_whitespace ();\r
+                       if (c == -1)\r
+                               return Token.EOF;\r
+\r
+                       if (is_identifier_start_character ((char)c)){\r
+                               tokens_seen = true;\r
+                               return consume_identifier (c, false);\r
+                       }\r
+\r
+               is_punct_label:\r
+                       if ((t = is_punct ((char)c, ref doread)) != Token.ERROR){\r
+                               tokens_seen = true;\r
+                               if (doread){\r
+                                       getChar ();\r
+                                       col++;\r
                                }\r
+                               return t;\r
+                       }\r
 \r
-                               if (c == '#') {\r
-                                       error_details = "Preprocessor directives must appear as the first non-whitespace " +\r
-                                               "character on a line.";\r
+                       if (c >= '0' && c <= '9'){\r
+                               tokens_seen = true;\r
+                               return is_number (c);\r
+                       }\r
 \r
-                                       Report.Error (1040, Location, error_details);\r
+                       if (c == '.'){\r
+                               tokens_seen = true;\r
+                               int peek = peekChar ();\r
+                               if (peek >= '0' && peek <= '9')\r
+                                       return is_number (c);\r
+                               return Token.DOT;\r
+                       }\r
+\r
+                       if (c == '"') \r
+                               return consume_string (false);\r
 \r
+                       if (c == '\''){\r
+                               c = getChar ();\r
+                               tokens_seen = true;\r
+                               if (c == '\''){\r
+                                       error_details = "Empty character literal";\r
+                                       Report.Error (1011, Location, error_details);\r
                                        return Token.ERROR;\r
                                }\r
+                               c = escape (c);\r
+                               if (c == -1)\r
+                                       return Token.ERROR;\r
+                               val = new System.Char ();\r
+                               val = (char) c;\r
+                               c = getChar ();\r
+\r
+                               if (c != '\''){\r
+                                       error_details = "Too many characters in character literal";\r
+                                       Report.Error (1012, Location, error_details);\r
 \r
-                               error_details = ((char)c).ToString ();\r
+                                       // Try to recover, read until newline or next "'"\r
+                                       while ((c = getChar ()) != -1){\r
+                                               if (c == '\n' || c == '\''){\r
+                                                       line++;\r
+                                                       ref_line++;\r
+                                                       col = 0;\r
+                                                       break;\r
+                                               } else\r
+                                                       col++;\r
+                                       }\r
+                                       return Token.ERROR;\r
+                               }\r
+                               return Token.LITERAL_CHARACTER;\r
+                       }\r
                                \r
+                       if (c == '@') {\r
+                               c = getChar ();\r
+                               if (c == '"') {\r
+                                       tokens_seen = true;\r
+                                       return consume_string (true);\r
+                               } else if (is_identifier_start_character ((char) c)){\r
+                                       return consume_identifier (c, true);\r
+                               } else {\r
+                                       Report.Error (1033, Location, "'@' must be followed by string constant or identifier");\r
+                               }\r
+                       }\r
+\r
+                       if (c == '#') {\r
+                               error_details = "Preprocessor directives must appear as the first non-whitespace " +\r
+                                       "character on a line.";\r
+\r
+                               Report.Error (1040, Location, error_details);\r
+\r
                                return Token.ERROR;\r
                        }\r
 \r
-                       return Token.EOF;\r
+                       error_details = ((char)c).ToString ();\r
+\r
+                       return Token.ERROR;\r
                }\r
 \r
                public void cleanup ()\r
@@ -1972,7 +2064,6 @@ namespace Mono.CSharp
                        }\r
                                \r
                }\r
-\r
        }\r
 }\r
 \r