is this a bug?

Bjorn Pettersen BPettersen at NAREX.com
Thu Aug 16 23:46:19 CEST 2001


> From: Vassilis Virvilis [mailto:vasvir at iit.demokritos.gr]
> 
> Brian Quinlan wrote:
> > 
> 
> > The bottom line is that you should rarely use the "is" 
> operator except
> > when testing if an object is None (there is only one None object in
> > Python).
> > 
> 
> Halo Brian,
> 
> So is it safe to do?
> if type(a) is type(b): blah blah

In general, no -- although it will probably work most of the time in the
current implementation (didn't look too closely). The general idiom is:

  import types
  ...
  if type(x) == types.IntType:
     ...

although many people also use:

  if type(x) == type(1):

-- bjorn




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