src/llex.h

   1 /*
   2 ** $Id: llex.h,v 1.12 1999/06/17 17:04:03 roberto Exp $
   3 ** Lexical Analyzer
   4 ** See Copyright Notice in lua.h
   5 */
   6
   7 #ifndef llex_h
   8 #define llex_h
   9
  10 #include "lobject.h"
  11 #include "lzio.h"
  12
  13
  14 #define FIRST_RESERVED  260
  15
  16 /* maximum length of a reserved word (+1 for terminal 0) */
  17 #define TOKEN_LEN       15
  18
  19 enum RESERVED {
  20   /* terminal symbols denoted by reserved words */
  21   AND = FIRST_RESERVED,
  22   DO, ELSE, ELSEIF, END, FUNCTION, IF, LOCAL, NIL, NOT, OR,
  23   REPEAT, RETURN, THEN, UNTIL, WHILE,
  24   /* other terminal symbols */
  25   NAME, CONC, DOTS, EQ, GE, LE, NE, NUMBER, STRING, EOS};
  26
  27
  28 #ifndef MAX_IFS
  29 #define MAX_IFS 5  /* arbitrary limit */
  30 #endif
  31
  32 /* "ifstate" keeps the state of each nested $if the lexical is dealing with. */
  33
  34 struct ifState {
  35   int elsepart;  /* true if it's in the $else part */
  36   int condition;  /* true if $if condition is true */
  37   int skip;  /* true if part must be skipped */
  38 };
  39
  40
  41 typedef struct LexState {
  42   int current;  /* look ahead character */
  43   int token;  /* look ahead token */
  44   struct FuncState *fs;  /* 'FuncState' is private for the parser */
  45   union {
  46     real r;
  47     TaggedString *ts;
  48   } seminfo;  /* semantics information */
  49   struct zio *lex_z;  /* input stream */
  50   int linenumber;  /* input line counter */
  51   int iflevel;  /* level of nested $if's (for lexical analysis) */
  52   struct ifState ifstate[MAX_IFS];
  53 } LexState;
  54
  55
  56 void luaX_init (void);
  57 void luaX_setinput (LexState *LS, ZIO *z);
  58 int luaX_lex (LexState *LS);
  59 void luaX_syntaxerror (LexState *ls, char *s, char *token);
  60 void luaX_error (LexState *ls, char *s);
  61 void luaX_token2str (int token, char *s);
  62
  63
  64 #endif