Persistent STL?

Discussion in 'C++' started by M?rio Amado Alves, Jun 8, 2004.

  1. Will you help an outsider trying to trace the current state of
    persistent object technology?

    "I expect that there will be persistent object stores with
    STL-conforming interfaces fitting into the STL framework within the
    next year."
    --Alexander Stepanov, 1995

    Has this happened? (In 1996 or another year.)

    Thanks a lot,
    --MAA
    M?rio Amado Alves, Jun 8, 2004
    #1
    1. Advertising

  2. M?rio Amado Alves wrote:
    > Will you help an outsider trying to trace the current state of
    > persistent object technology?


    I don't know the state of this but Objectivity offered at some
    point STL-like containers which could be made persistent.

    Unfortunately, it is impossible to create proxy containers
    conforming to the container or sequence requirements (essentially,
    because operator*() is required to return a reference). This would
    allow some lightweight persistance mechanisms, e.g. persistent
    containers. Of course, my property map approach would solve this
    problem, too (well, actually, you wouldn't necessarily need property
    maps per se but the separation of reads and writes).
    >
    > "I expect that there will be persistent object stores with
    > STL-conforming interfaces fitting into the STL framework within the
    > next year."
    > --Alexander Stepanov, 1995


    I think he was wrong. Some of the decisions in STL make it hard if not
    impossible to create persistent object stores with STL conformant
    interfaces.
    --
    <mailto:> <http://www.dietmar-kuehl.de/>
    <http://www.contendix.com> - Software Development & Consulting
    Dietmar Kuehl, Jun 8, 2004
    #2
    1. Advertising

  3. M?rio Amado Alves

    Jeff Flinn Guest

    "M?rio Amado Alves" <> wrote in message
    news:...
    > Will you help an outsider trying to trace the current state of
    > persistent object technology?
    >
    > "I expect that there will be persistent object stores with
    > STL-conforming interfaces fitting into the STL framework within the
    > next year."
    > --Alexander Stepanov, 1995
    >
    > Has this happened? (In 1996 or another year.)


    In addition to Dietmar's response, and depending on your definition of
    "persistent" there is a "serialization" library near completion at
    www.boost.org. This is an excellent library by Robert Ramey which in
    pre-release form can be downloaded from www.rrsd.com. It offers
    out-of-the-box support for most(if not all) STL containers, along with
    boost::shared_ptr.

    Jeff F.
    Jeff Flinn, Jun 8, 2004
    #3
  4. In message <ca521d$qhq$>, Jeff Flinn
    <> writes
    >
    >"M?rio Amado Alves" <> wrote in message
    >news:...
    >> Will you help an outsider trying to trace the current state of
    >> persistent object technology?
    >>
    >> "I expect that there will be persistent object stores with
    >> STL-conforming interfaces fitting into the STL framework within the
    >> next year."
    >> --Alexander Stepanov, 1995
    >>
    >> Has this happened? (In 1996 or another year.)

    >
    >In addition to Dietmar's response, and depending on your definition of
    >"persistent" there is a "serialization" library near completion at
    >www.boost.org. This is an excellent library by Robert Ramey which in
    >pre-release form can be downloaded from www.rrsd.com. It offers
    >out-of-the-box support for most(if not all) STL containers, along with
    >boost::shared_ptr.


    My feeling is that "persistent" ought to mean not just "serializable"
    but also "transparent". That would require, among other things, that:

    - use of a reference/pointer automatically loads the referenced
    persistent object;
    - some kind of GC process removes unused objects from memory, saving as
    necessary;
    - the library manages how objects are located within the file.

    All of this is perhaps nearer to the idea of an object database than
    simple persistent objects. I did a little searching on that subject a
    few years ago, but didn't pursue it far. There were a variety of
    solutions being offered, both commercial and free, but I don't think
    there's anything which offers complete STL compatibility.

    In the commercial sphere the big names seem to be Objectivity,
    Versant/Poet, ObjectStore... and no doubt many others by now; at the
    free end there's TEXAS from the University of Texas
    (ftp://ftp.cs.utexas.edu/pub/garbage/texas/, last changed 1996) and
    POST++ (http://www.garret.ru/~knizhnik/post/readme.htm)

    --
    Richard Herring
    Richard Herring, Jun 9, 2004
    #4
  5. Excelent information! Extremely helpful! Thanks all very much!

    I feel I owe some explanation of what I need this for. I'm preparing a
    presentation on persistent containers, with references to the STL, for
    RST 2004 (http://dmi.uib.es/~AE2004) I just wanted to make sure I
    would not be boobooing too much when I say Stepanov's prediction in
    1995 for 1996 is still uncomplished in 2004. I'm also developing a
    persistent graph container called Mneson
    (http://www.liacc.up.pt/~maa/mnesosn). It's in Ada but there are plans
    to provide interfaces for C++ (as well as to C and Java). All this is
    connected to the fact that the upcoming Ada.Containers library for Ada
    2005 is partially modelled on the STL. I'll be thrilled to discuss
    more if you want but please note I'm not a regular of this group so
    please do it privately or in comp.lang.ada. Thanks.
    M?rio Amado Alves, Jun 9, 2004
    #5
    1. Advertising

Want to reply to this thread or ask your own question?

It takes just 2 minutes to sign up (and it's free!). Just click the sign up button to choose a username and then you can ask your own questions on the forum.
Similar Threads
  1. Allan Bruce

    To STL or not to STL

    Allan Bruce, Oct 16, 2003, in forum: C++
    Replies:
    41
    Views:
    1,041
    Christopher Benson-Manica
    Oct 17, 2003
  2. Replies:
    4
    Views:
    797
    Daniel T.
    Feb 16, 2006
  3. Replies:
    2
    Views:
    552
    klaus hoffmann
    Feb 22, 2006
  4. Replies:
    5
    Views:
    503
    Markus Schoder
    Apr 16, 2006
  5. gk
    Replies:
    7
    Views:
    966
    Tom Anderson
    Oct 12, 2010
Loading...

Share This Page