int32 conv_num(struct script_state* st, struct script_data* data) {
	char* p;
	int32 num;

	script->get_val(st, data);
	if( data_isint(data) )
	{// nothing to convert
	}
	else if( data_isstring(data) )
	{// string -> int
		// the result does not overflow or underflow, it is capped instead
		// ex: 999999999999 is capped to INT_MAX (2147483647)
		p = data->u.str;
		errno = 0;
		num = strtol(data->u.str, NULL, 10);// change radix to 0 to support octal numbers "o377" and hex numbers "0xFF"
		if( errno == ERANGE
#if LONG_MAX > INT_MAX
			|| num < INT_MIN || num > INT_MAX
#endif
			)
		{
			if( num <= INT_MIN )
			{
				num = INT_MIN;
				ShowError("script:conv_num: underflow detected, capping to %ld\n", num);
			}
			else//if( num >= INT_MAX )
			{
				num = INT_MAX;
				ShowError("script:conv_num: overflow detected, capping to %ld\n", num);
			}
			script_reportdata(data);
			script_reportsrc(st);
		}
		if( data->type == C_STR )
			aFree(p);
		data->type = C_INT;
		data->u.num = num;
	}
#if 0
	// FIXME this function is being used to retrieve the position of labels and
	// probably other stuff [FlavioJS]
	else
	{// unsupported data type
		ShowError("script:conv_num: cannot convert to number, defaulting to 0\n");
		script_reportdata(data);
		script_reportsrc(st);
		data->type = C_INT;
		data->u.num = 0;
	}
#endif
	return (int32)data->u.num;
}