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llex.h (2404B)

      1 /*
      2 ** $Id: llex.h $
      3 ** Lexical Analyzer
      4 ** See Copyright Notice in lua.h
      5 */
      6 
      7 #ifndef llex_h
      8 #define llex_h
      9 
     10 #include <limits.h>
     11 
     12 #include "lobject.h"
     13 #include "lzio.h"
     14 
     15 
     16 /*
     17 ** Single-char tokens (terminal symbols) are represented by their own
     18 ** numeric code. Other tokens start at the following value.
     19 */
     20 #define FIRST_RESERVED	(UCHAR_MAX + 1)
     21 
     22 
     23 #if !defined(LUA_ENV)
     24 #define LUA_ENV		"_ENV"
     25 #endif
     26 
     27 
     28 /*
     29 * WARNING: if you change the order of this enumeration,
     30 * grep "ORDER RESERVED"
     31 */
     32 enum RESERVED {
     33   /* terminal symbols denoted by reserved words */
     34   TK_AND = FIRST_RESERVED, TK_BREAK,
     35   TK_DO, TK_ELSE, TK_ELSEIF, TK_END, TK_FALSE, TK_FOR, TK_FUNCTION,
     36   TK_GOTO, TK_IF, TK_IN, TK_LOCAL, TK_NIL, TK_NOT, TK_OR, TK_REPEAT,
     37   TK_RETURN, TK_THEN, TK_TRUE, TK_UNTIL, TK_WHILE,
     38   /* other terminal symbols */
     39   TK_IDIV, TK_CONCAT, TK_DOTS, TK_EQ, TK_GE, TK_LE, TK_NE,
     40   TK_SHL, TK_SHR,
     41   TK_DBCOLON, TK_EOS,
     42   TK_FLT, TK_INT, TK_NAME, TK_STRING
     43 };
     44 
     45 /* number of reserved words */
     46 #define NUM_RESERVED	(cast_int(TK_WHILE-FIRST_RESERVED + 1))
     47 
     48 
     49 typedef union {
     50   lua_Number r;
     51   lua_Integer i;
     52   TString *ts;
     53 } SemInfo;  /* semantics information */
     54 
     55 
     56 typedef struct Token {
     57   int token;
     58   SemInfo seminfo;
     59 } Token;
     60 
     61 
     62 /* state of the scanner plus state of the parser when shared by all
     63    functions */
     64 typedef struct LexState {
     65   int current;  /* current character (charint) */
     66   int linenumber;  /* input line counter */
     67   int lastline;  /* line of last token 'consumed' */
     68   Token t;  /* current token */
     69   Token lookahead;  /* look ahead token */
     70   struct FuncState *fs;  /* current function (parser) */
     71   struct lua_State *L;
     72   ZIO *z;  /* input stream */
     73   Mbuffer *buff;  /* buffer for tokens */
     74   Table *h;  /* to avoid collection/reuse strings */
     75   struct Dyndata *dyd;  /* dynamic structures used by the parser */
     76   TString *source;  /* current source name */
     77   TString *envn;  /* environment variable name */
     78 } LexState;
     79 
     80 
     81 LUAI_FUNC void luaX_init (lua_State *L);
     82 LUAI_FUNC void luaX_setinput (lua_State *L, LexState *ls, ZIO *z,
     83                               TString *source, int firstchar);
     84 LUAI_FUNC TString *luaX_newstring (LexState *ls, const char *str, size_t l);
     85 LUAI_FUNC void luaX_next (LexState *ls);
     86 LUAI_FUNC int luaX_lookahead (LexState *ls);
     87 LUAI_FUNC l_noret luaX_syntaxerror (LexState *ls, const char *s);
     88 LUAI_FUNC const char *luaX_token2str (LexState *ls, int token);
     89 
     90 
     91 #endif