Re: once again about TClonesArray

Victor Perevoztchikov (perev@bnl.gov)
Wed, 23 Dec 1998 20:26:19 -0500

Hi Pasha,
...
> This would allow to decouple to a certain extent the use of TClonesArray's and
> the generation of the dictionaries which would be very nice from the point of
> view of general design.

TClonesArray and TObjArray have principal difference.

In TObjArray user creates the object and then saves its pointer into TObjArray.

In TCloneArray creation is made inside TCloneArray class by special new operator
which allows reuse space. The same with delete, which actually did not do
real delete but only marks this part of memory as a free.

But in C++ you can not create the object defined by textual name of class. In TCloneArray
there is only text name of class. Somewhere must be compiled code like
"pointer = new Classname();"
This code is provided by CINT and then this code is compiled. Access to this compiled
code is possible only via CINT dictionary.

So, TCloneArray is principally linked with CINT and CINT dictionary.

Merry Xmass
Victor

-- 
Victor M. Perevoztchikov   perev@bnl.gov  perev@vxcern.cern.ch       
Brookhaven National Laboratory MS 510A PO Box 5000 Upton NY 11973-5000
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