String Replace

wiki

  static int str_replace(lua_State *L) {
    size_t l1, l2, l3;
    const char *src = luaL_checklstring(L, 1, &l1);
    const char *p = luaL_checklstring(L, 2, &l2);
    const char *p2 = luaL_checklstring(L, 3, &l3);
    const char *s2;
    int n = 0;
    int init = 0;

    luaL_Buffer b;
    luaL_buffinit(L, &b);

   while (1) {
     s2 = lmemfind(src+init, l1-init, p, l2);
     if (s2) {
		 luaL_addlstring(&b, src+init, s2-(src+init));
		 luaL_addlstring(&b, p2, l3);
		 init = init + (s2-(src+init)) + l2;
		 n++;
     } else {
	    luaL_addlstring(&b, src+init, l1-init);
	    break;
	 }
   }


   luaL_pushresult(&b);
   lua_pushnumber(L, (lua_Number)n);  /* number of substitutions */
   return 2;
 }


--*note  add new the 'replace' function to strlib 

static const luaL_reg strlib[] = {
   {"len", str_len},
   {"sub", str_sub},
   {"lower", str_lower},
   {"upper", str_upper},
   {"char", str_char},
   {"getchar", str_getchar},
   {"rep", str_rep},
   {"byte", str_byte},
   {"format", str_format},
   {"dump", str_dump},
   {"find", str_find},
   {"gfind", gfind},
   {"gsub", str_gsub},
   {"replace", str_replace},
   {NULL, NULL}
 };