/*

** $Id: llex.h,v 1.47 2003/02/28 17:19:47 roberto Exp $

** Lexical Analyzer

** See Copyright Notice in lua.h

*/



#ifndef llex_h

#define llex_h



#include "lobject.h"

#include "lzio.h"





#define FIRST_RESERVED	257



/* maximum length of a reserved word */

#define TOKEN_LEN	(sizeof("function")/sizeof(char))





/*

* WARNING: if you change the order of this enumeration,

* grep "ORDER RESERVED"

*/

enum RESERVED {

  /* terminal symbols denoted by reserved words */

  TK_AND = FIRST_RESERVED, TK_BREAK,

  TK_DO, TK_ELSE, TK_ELSEIF, TK_END, TK_FALSE, TK_FOR, TK_FUNCTION,

  TK_IF, TK_IN, TK_LOCAL, TK_NIL, TK_NOT, TK_OR, TK_REPEAT,

  TK_RETURN, TK_THEN, TK_TRUE, TK_UNTIL, TK_WHILE,

  /* other terminal symbols */

  TK_NAME, TK_CONCAT, TK_DOTS, TK_EQ, TK_GE, TK_LE, TK_NE, TK_NUMBER,

  TK_STRING, TK_EOS

};



/* number of reserved words */

#define NUM_RESERVED	(cast(int, TK_WHILE-FIRST_RESERVED+1))





typedef union {

  lua_Number r;

  TString *ts;

} SemInfo;  /* semantics information */





typedef struct Token {

  int token;

  SemInfo seminfo;

} Token;





typedef struct LexState {

  int current;  /* current character (charint) */

  int linenumber;  /* input line counter */

  int lastline;  /* line of last token `consumed' */

  Token t;  /* current token */

  Token lookahead;  /* look ahead token */

  struct FuncState *fs;  /* `FuncState' is private to the parser */

  struct lua_State *L;

  ZIO *z;  /* input stream */

  Mbuffer *buff;  /* buffer for tokens */

  TString *source;  /* current source name */

  int nestlevel;  /* level of nested non-terminals */

} LexState;





void luaX_init (lua_State *L);

void luaX_setinput (lua_State *L, LexState *LS, ZIO *z, TString *source);

int luaX_lex (LexState *LS, SemInfo *seminfo);

void luaX_checklimit (LexState *ls, int val, int limit, const char *msg);

void luaX_syntaxerror (LexState *ls, const char *s);

void luaX_errorline (LexState *ls, const char *s, const char *token, int line);

const char *luaX_token2str (LexState *ls, int token);





#endif

