Thank you Manfred.

[...]

Looks like an awful lot of repetition, and would have to take a closer
look at your problem for advice on design.  However, to get you going,
below is the Boost.PP work to do what you want - but think even that
could be done better..


This is the design of the lib I use. The class I need is templated and policy based. Usually, when I know the instanciation I would like to have, I define a typedef and use it in the rest of the programm. Now, to be more generic, the programm need to let a user choose how to instanciate the class. If you have any idea about a better design, I will be very interesting in reading it.

Best regards,

Olivier


--
Dr. Olivier Tournaire
MATIS - Institut Géographique National
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