[Tutor] Object problem in python 1.5.2

[Ibraheem Umaru-Mohammed]

["Guillermo Fernandez"="Guillermo"]
				.
				.
				.
Guillermo >> 
Guillermo >> The code is:
Guillermo >> In a Class:
Guillermo >> 
Guillermo >>     def _evaluate(self, mylist):
Guillermo >>         """Evaluate the program stored in the list
Guillermo >>         IN : The list
Guillermo >>         OUT:"""
Guillermo >> 
Guillermo >>         def iffood():
Guillermo >>             # Is there food in front of us?
Guillermo >> line 400 -> length=int(math.sqrt(len(self._temp_map)))
Guillermo >>             if self._direction == 0:
Guillermo >>                 return self._temp_map[self._x_pos+length*
Guillermo >>                                       int(math.fmod((self._y_pos-1),
Guillermo >> length))]
Guillermo >>             elif self._direction == 1:
Guillermo >>                 return self._temp_map[int(math.fmod((self._x_pos+1),
Guillermo >> length))+
Guillermo >>                                       length*self._y_pos]
Guillermo >>             elif self._direction == 2:
Guillermo >>                 return self._temp_map[self._x_pos+length*
Guillermo >>                                       int(math.fmod((self._y_pos+1),
Guillermo >> length))]
Guillermo >>             elif self._direction == 3:
Guillermo >>                 return self._temp_map[int(math.fmod((self._x_pos-1),
Guillermo >> length))+
Guillermo >>                                       length*self._y_pos]
Guillermo >>             else:
Guillermo >>                 print "Error"
Guillermo >> 
Guillermo >>         executed=0
Guillermo >>         length=int(math.sqrt(len(self._temp_map)))
Guillermo >>         result=mylist[0]
Guillermo >>         if result == "iffood":
Guillermo >>       ETC, ETC, ETC...
Guillermo >> 
Guillermo >> Have the object interface changed in such a manner that self is not
Guillermo >> recognized anymore?
Guillermo >> 
Guillermo >> Of course, the original 2.2 code runs perfectly fine.
Guillermo >> 
Guillermo >> Thanks!
Guillermo >> 
Guillermo >> Guille

I believe the issue here is one of "nested scopes". Before Python2.2,
names were resolved using the LGB princible (Local, Global, Built-in
namespaces). Since nested scopes have been introduced, unbound names can
be resolved from the enclosing function space. So in the example above,
the method "iffood" is defined within "_evaluate", therefore any
unresolved names in "iffood" are searched for in the "_evaluate"
method's scope. In this case, "self" and "mylist" are resolved in the
enclosing "_evaluate" namespace.


Kindest regards,

			--ibs.

-- 
				Ibraheem Umaru-Mohammed 
					"ibz"
			umarumohammed (at) btinternet (dot) com