[Tutor] Pickling in plain English

[Tom Tucker]

John,
Thanks that did help.  Like usual, I was making it harder than necessary.  

Tom,
I concur! Well put!

On 5/24/05, Tom Cloyd <tomcloyd at bestmindhealth.com> wrote:
> I just want to take a moment to express my deep appreciation for this
> List. As one who is learning Python as amateur, in my spare moments, and
> already getting it to do good work for me, these clear, beautifully worked
> descriptions of basic aspects of Python are simply an ongoing delight for
> me - and singularly useful to my study of Python. To those of you who give
> your time, thought, and experience here to those of us who need it, thank
> you so very much.
> 
> Tom Cloyd
> 
> On Tue, 24 May 2005 16:32:50 -0700, <jfouhy at paradise.net.nz> wrote:
> 
> > Quoting Tom Tucker <tktucker at gmail.com>:
> >
> >> I am having trouble understanding the c|Pickle modules. What does
> >> serializing and de-serializing objects mean? I have read the below
> >> urls and I "think" I understand the process, but I can't visualize the
> >> beneifts. Can someone kindly explain pickling in lamens terms?
> >
> > It's actually astonishingly simple, once you get the hang of it.
> >
> > example:
> >
> >>>> arr = [1, 3, 5, 7]
> >>>> dct = {'foo':1, 'bar':2, 'baz':3}
> >>>> st = "re: your mail"
> >>>>
> >>>> import pickle
> >>>> f = file('dump', 'wb')
> >>>> pickle.dump((arr, dct, st), f)
> >>>> f.close()
> >>>> ^Z
> >
> > [new instance of python]
> >
> >>>> import pickle
> >>>> f = file('dump', 'r')
> >>>> res = pickle.load(f)
> >>>> res
> > ([1, 3, 5, 7], {'bar': 2, 'foo': 1, 'baz': 3}, 're: your mail')
> >
> > [and you can look at the file 'dump' on your HDD, if you want to]
> >
> > Basically, pickle allows you to write any python object to disk and the
> > load it
> > back again with very little effort.  This is important if you want your
> > program
> > to be able to save state between instances.
> >
> > You can pickle more complex objects; the only restriction is that
> > pickle.load
> > must be able to find the module where the classes are defined.
> >
> > [there are some other restrictions, but you can do a lot without
> > worrying about
> > them]
> >
> > Does this help?
> >
> 
> 
> 
> --
> 
> ======================================================
> Tom Cloyd
> Bellingham, Washington, U.S.A: (360) 920-1226
> << BestMindHealth.com >>
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