func_code vs. string problem

[Filip Dreger]

Uzytkownik "Steven Bethard" <steven.bethard at gmail.com> napisal w 
wiadomosci news:QvKdnZAEj5TEKfffRVn-oQ at comcast.com...
> Filip Dreger wrote:
>> I am trying to find a way of executing functions without creating a 
>> nested scope, so they can share local and global namespace (even if 
>> they are declared in some other module).
>
> Why?  Can you explain what the use case is?

I have a large set of objects of a single class - 'actor'. They are 
created all at once, and they all live in a sort of container written 
in C. The methods of the functions are few and general. One of them is 
simply 'act()', that is called by the C program every X seconds (tics, 
whatever).
Each object can play 0..N roles, and the roles played by an object 
often change during its lifetime. The roles should be played in the 
act() method. Also, the roles should be defined in some simple way, 
and in an external python file (so adding/removing roles does not 
require recompiling of the parts embedded in C).

If I had a magic function 'exec in current scope' I would implement it 
like this:

class actor:
  def __init__():
    self.roles=[]
  def act():
    for i in self.roles:
      exec i in current scope

then the roles would simply be functions defined in any importable 
file. For example creating an actor that logs each time it is called 
would be as simple as:

import actor

def log():
  self.counter+=1
  print "called %d times"%self.counter

a=actor.actor()
a.counter=0
a.roles.append(log)

Let me recapitulate (is that the right English word?):
1. I need to keep the definitions of roles in a separate file (they 
can not simply be additional methods)
2. I need the roles to have full access to global and local namespace 
of the actor object (sometimes they have to change it, and sometimes 
they have to use some external modules) - the roles should work like 
plugins.
3. I guess I also need a fresh look at the problem. Maybe I am simply 
going the wrong way? I am more than willing to change my design, if 
someone shows me the light :-)

regards,
Filip Dreger