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Re: Why does 1**2**3**4**5 raise a MemoryError?

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Dave Angel wrote:

> On 03/31/2013 02:56 AM, morphex wrote:
> > > > > 1**2
> > 1
> > > > > 1**2**3
> > 1
> > > > > 1**2**3**4
> > 1L
> > > > > 1**2**3**4**5
> > Traceback (most recent call last):
> >   File "<stdin>", line 1, in <module>
> > MemoryError
> > > > > 
> > 
> > Does anyone know why this raises a MemoryError?  Doesn't make sense
> > to me.
> 
> Perhaps you didn't realize that the expression will be done from
> right to left.  

Really? 

The Python 3 documentation
(http://docs.python.org/3/reference/expressions.html) says in section
6.14 (Evaluation order) that "Python evaluates expressions from left to
right" (an exception being when evaluating assignments, in which case
the RHS of the assignment is calculated first, in left-to-right order).

Section 6.4 discusses the power operator specifically and does not
contradict 6.14 except that the power operator uses right-to-left
evaluation in the presence of unparenthesized unary operators.

Neither of these two exception cases appear to apply here, so I think
the OP is reasonable in expecting Python to do the operation
left-to-right.

Am I missing something written somewhere else in the docs? Are the docs
I quoted wrong? Please help me understand the discrepancy I am
perceiving here.

Alex

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Thread

Why does 1**2**3**4**5 raise a MemoryError? morphex <morphex@gmail.com> - 2013-03-30 23:56 -0700
  Re: Why does 1**2**3**4**5 raise a MemoryError? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-03-31 07:33 +0000
    Re: Why does 1**2**3**4**5 raise a MemoryError? Dave Angel <davea@davea.name> - 2013-03-31 03:48 -0400
    Re: Why does 1**2**3**4**5 raise a MemoryError? morphex <morphex@gmail.com> - 2013-03-31 05:07 -0700
      Re: Why does 1**2**3**4**5 raise a MemoryError? Dave Angel <d@davea.name> - 2013-03-31 08:43 -0400
        Re: Why does 1**2**3**4**5 raise a MemoryError? Roy Smith <roy@panix.com> - 2013-03-31 09:15 -0400
          Re: Why does 1**2**3**4**5 raise a MemoryError? Jason Swails <jason.swails@gmail.com> - 2013-03-31 10:03 -0400
      Re: Why does 1**2**3**4**5 raise a MemoryError? Roy Smith <roy@panix.com> - 2013-03-31 09:04 -0400
      Re: Why does 1**2**3**4**5 raise a MemoryError? Tim Roberts <timr@probo.com> - 2013-04-01 21:45 -0700
        Re: Why does 1**2**3**4**5 raise a MemoryError? Chris Angelico <rosuav@gmail.com> - 2013-04-02 17:16 +1100
        Re: Why does 1**2**3**4**5 raise a MemoryError? Dan Sommers <dan@tombstonezero.net> - 2013-04-02 12:56 +0000
    Re: Why does 1**2**3**4**5 raise a MemoryError? Roy Smith <roy@panix.com> - 2013-03-31 08:59 -0400
  Re: Why does 1**2**3**4**5 raise a MemoryError? Dave Angel <davea@davea.name> - 2013-03-31 03:34 -0400
    Re: Why does 1**2**3**4**5 raise a MemoryError? "Alex" <foo@email.invalid> - 2013-03-31 22:06 +0000
      Re: Why does 1**2**3**4**5 raise a MemoryError? Chris Angelico <rosuav@gmail.com> - 2013-04-01 09:28 +1100
        Re: Why does 1**2**3**4**5 raise a MemoryError? "Alex" <foo@email.invalid> - 2013-04-01 00:39 +0000
          Re: Why does 1**2**3**4**5 raise a MemoryError? Chris Angelico <rosuav@gmail.com> - 2013-04-01 11:58 +1100
          Re: Why does 1**2**3**4**5 raise a MemoryError? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-04-01 04:16 +0000
            Re: Why does 1**2**3**4**5 raise a MemoryError? Roy Smith <roy@panix.com> - 2013-04-01 07:48 -0400
          Re: Why does 1**2**3**4**5 raise a MemoryError? Nobody <nobody@nowhere.com> - 2013-04-02 08:40 +0100
      Re: Why does 1**2**3**4**5 raise a MemoryError? Chris Angelico <rosuav@gmail.com> - 2013-04-01 09:32 +1100
      Re: Why does 1**2**3**4**5 raise a MemoryError? Dave Angel <davea@davea.name> - 2013-03-31 18:34 -0400

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