finding name of instances created

Steven Bethard steven.bethard at gmail.com
Sun Jan 23 22:01:12 CET 2005


Michael Tobis wrote:
> I have a similar problem. Here's what I do:
> 
> .def new_robot_named(name,indict=globals()):
> .   execstr = name + " = robot('" + name + "')"
> .   exec(execstr,indict)
> 
> .class robot(object):
> .   def __init__(self,name):
> .      self.name = name
> 
> .   def sayhi(self):
> .      print "Hi!  I'm %s!" % self.name
> 
> .if __name__=="__main__":
> .   new_robot_named('Bert')
> .   new_robot_named('Ernie')
> .   Ernie.sayhi()
> .   Bert.sayhi()
> 

If you're changing the syntax from
     alex = CreateRobot()
to
     new_robot_named('Alex')
I don't see what you gain from using exec...

py> class robot(object):
...    def __init__(self,name):
...       self.name = name
...    def sayhi(self):
...       print "Hi!  I'm %s!" % self.name
...
py> def new_robot_named(name, indict=globals()):
...     indict[name] = robot(name)
...
py> new_robot_named('Bert')
py> new_robot_named('Ernie')
py> Ernie.sayhi()
Hi!  I'm Ernie!
py> Bert.sayhi()
Hi!  I'm Bert!
py> import new
py> temp = new.module('temp')
py> new_robot_named('Alex', temp.__dict__)
py> temp.Alex.sayhi()
Hi!  I'm Alex!

That said, I do think a 'new_robot_named' function is probably a better 
approach than trying to change the meaning of Python's assignment 
statement...

Steve



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