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Re: chunking a long string?

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On Sun, Nov 10, 2013 at 2:21 AM, Roy Smith <roy@panix.com> wrote:
> But, you missed the point of my question.  You said that Python does
> this "only when you ask for it".  That implies it never interns strings
> if you don't ask for it, which is clearly not true:
>
> $ python
> Python 2.7.1 (r271:86832, Jul 31 2011, 19:30:53)
> [...]
>>>> x = "foo"
>>>> y = "foo"
>>>> x is y
> True

Ah! Yes, that's true; literals are interned - I forgot that. But
anything from an external source won't be, hence my example with
reading in the contents of a file.

> I think what you're trying to say is that there are several possible
> interning policies:
>
> 1) Strings are never interned
>
> 2) Strings are always interned
>
> 3) Strings are optionally interned, at the discretion of the
> implementation
>
> 4) The user may force a specific string to be interned by explicitly
> requesting it.
>
> and that Pike implements #1, while Python implements #3 and #4.

Pike implements #2, I presume that was a typo. And yes, the interning
of literals falls under #3, while sys.intern() gives #4. Use of #1
would be restricted to languages with mutable strings, I would expect,
for the same reason that Python tuples might be shared but lists won't
be.

ChrisA

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Thread

chunking a long string? Roy Smith <roy@panix.com> - 2013-11-08 12:48 -0500
  Re: chunking a long string? wxjmfauth@gmail.com - 2013-11-08 12:43 -0800
    Re: chunking a long string? Chris Angelico <rosuav@gmail.com> - 2013-11-09 07:53 +1100
    Re: chunking a long string? Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-11-08 20:57 +0000
    Re: chunking a long string? Tim Chase <python.list@tim.thechases.com> - 2013-11-08 15:04 -0600
    Re: chunking a long string? Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-11-08 21:06 +0000
    Re: chunking a long string? Chris Angelico <rosuav@gmail.com> - 2013-11-09 08:04 +1100
    Re: chunking a long string? Chris Angelico <rosuav@gmail.com> - 2013-11-09 08:17 +1100
    Re: chunking a long string? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-11-09 00:46 +0000
      Re: chunking a long string? wxjmfauth@gmail.com - 2013-11-09 00:14 -0800
        Re: chunking a long string? Chris Angelico <rosuav@gmail.com> - 2013-11-09 19:26 +1100
          Re: chunking a long string? Roy Smith <roy@panix.com> - 2013-11-09 09:37 -0500
            Re: chunking a long string? Chris Angelico <rosuav@gmail.com> - 2013-11-10 02:02 +1100
              Re: chunking a long string? Roy Smith <roy@panix.com> - 2013-11-09 10:21 -0500
                Re: chunking a long string? Chris Angelico <rosuav@gmail.com> - 2013-11-10 02:30 +1100
                Re: chunking a long string? Roy Smith <roy@panix.com> - 2013-11-09 10:35 -0500
            Re: chunking a long string? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-11-09 15:37 +0000
              Re: chunking a long string? Chris Angelico <rosuav@gmail.com> - 2013-11-10 09:14 +1100
                Re: chunking a long string? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-11-10 06:39 +0000
                Re: chunking a long string? Chris Angelico <rosuav@gmail.com> - 2013-11-10 19:46 +1100
        Re: chunking a long string? Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-11-09 10:13 +0000
  Re: chunking a long string? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-11-09 00:54 +0000

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