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/*

* proxy.c

* lexer proxy for Lua parser -- implements __FILE__ and __LINE__

* Luiz Henrique de Figueiredo

* This code is hereby placed in the public domain.

* Add <<#include "proxy.c">> just before the definition of luaX_next in llex.c

*/



#include <string.h>



static int nexttoken(LexState *ls, SemInfo *seminfo)

{

  int t=llex(ls,seminfo);

  if (t==TK_NAME) {

    if (strcmp(getstr(seminfo->ts),"__FILE__")==0) {

      t=TK_STRING;

      seminfo->ts = ls->source;

    }

    else if (strcmp(getstr(seminfo->ts),"__LINE__")==0) {

      t=TK_NUMBER;

      seminfo->r = ls->linenumber;

    }

  }

  return t;

}



#define llex nexttoken

An equivalent pure Lua code could be:

function __FILE__() return debug.getinfo(2,'S').source end

function __LINE__() return debug.getinfo(2, 'l').currentline end