Hello Craig,

On Jul 31 13:42 94, Craig Swanson of 1:202/354 wrote:

 CS> as the "POET Object Database for C++".  There is an 


Here's some more experience with POET 2.1 for OS/2:

a) the preProcessor (PTXX) is at C++ Level 2.0, which makes it impossible,
to make a ANSI C++ (Level 3) Class persistent. This includes 
.) nested classes 
  sample: class a { public: class b {};};
          class c { public: class b {};};
  error : redefinition of class b; // wrong. this is C++ 3.0
.) nested typedefs
  sample:
    class a;
    class b : public a { typedef a inherited; };
  note : IBM CSET++ ICLUI classes uses this method.
.) templates
  note : IBM CSET++ ICC classes are template based.
  so, you have either to use the list, set classes from poet [see below] or
write your own [whats about code reuse ?] or buy very simple container
classes.
.) additional there are bugs in PTXX:
  sample:

 class IString; // forward def. not needed to know anything about this class
 class test { IString asDebugInfo(); };

 error : don't know the size of IString. // why on earth does he need to
know the size???

.) POETS built in List/Set classes are VERY simple. 
 x) the compact version is a simple array with 'short' dimension.
 x) the large version is a array of 64K arrays [or something alike].
 x) the huge version alike the large version for OS/2 (in 16bit envirs
there is a keyword 'huge' used in front of the data.

so, my impression is: as long as the classes you want to make persistent
are simple and only contains C++ 2.0 interface descriptions, POET gives you
a useable OODB. if you have complex classes, or you want to make classes
from other vendors persistent, there will be a hard way to go.

additional literature :
.) BYTE 4/94 : special report on OODB's
.) BYTE 5/94 : POET in motion. [a test of POET 2.1 for Windows]

PS: if you have any experience in other OODB's which are available for OS/2
and other platforms, i'm very interested in reading something. 

Mario

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