curious problem with large numbers - Due to subprocess - using pickle

[Michael Spencer]

Michael Spencer wrote:

>>
> Problem is associated with executing iteractive input in a subprocess.
> 
>  >python idle.py -n
> 
> IDLE 1.1      ==== No Subprocess ====
>  >>> 1e10000
> 1.#INF
>  >>>
> 
> Michael
> 
> 
It seems that the culprit is pickle - used to send messages between the IDLE 
shell and the execution server.
  >>> import pickle

  >>> pickle.dumps(1e10000)
  'F1.#INF\n.'
  >>> pickle.loads(_)
  Traceback (most recent call last):
    File "<input>", line 1, in ?
    File "c:\python24\lib\pickle.py", line 1394, in loads
      return Unpickler(file).load()
    File "c:\python24\lib\pickle.py", line 872, in load
      dispatch[key](self)
    File "c:\python24\lib\pickle.py", line 968, in load_float
      self.append(float(self.readline()[:-1]))
  ValueError: invalid literal for float(): 1.#INF
  >>> import cPickle as pickle
  >>> pickle.dumps(1e10000)
  'F1.#INF\n.'
  >>> pickle.loads(_)
  Traceback (most recent call last):
    File "<input>", line 1, in ?
  ValueError: could not convert string to float
  >>>

  It seems that somewhere IDLE traps this error and shows '1.0' instead. 
However, I can't follow the IDLE output code, so I won't try to track this down 
any further

  IDLE 1.1
 >>> 2e10000
1.0
 >>> 3e10000
1.0
 >>> 100e10000
1.0
 >>> 999e1000
1.0
 >>>

Michael