gdb - pretty printer help: object has no attribute -

i writing first pretty printer, have trouble. gdb 7.7.

here c++ code debug:

enum country {     china,     usa };  class foo {    public:        foo(int _v, enum country c) {v = _v; m_country = c;}        ~foo() { v = -1; }         int v;        enum country m_country; };  int main() {     foo f(10, china);      return 0; } 

here printer:

import gdb   class fooprinter:     def __init__(self, val):         self.v = val      def to_string(self):         # because v integer, simpler way is:         # return self.v['v']         v = "v=" + str(self.v['v'])          f = self.m_country['m_country']         if (f == 0):             c = "china"         elif (f == 1):                                                                                                                                                                                    c = "usa"                                                                                                                                                                                 else:                                                                                                                                                                                             c = "unknown"          c = "c=" + c          ret = v + '\n' + c          return ret   def lookup_type (val):     if str(val.type) == 'foo':         return fooprinter(val)     return none  gdb.pretty_printers.append (lookup_type) 

when run printer in gdb, error:

(gdb) source printer.py  (gdb) p f python exception <class 'attributeerror'> 'fooprinter' object has no attribute 'm_country':  

i guess need somehow modify __init__ take country argument, if so, how should update rest of code?

the problem line:

    f = self.m_country['m_country'] 

here think want examine self.v instead:

    f = self.v['m_country'] 

note can enumeration constant names enum type. so, can replace chained if simpler lookup. nice if enum larger couple of constants.