How to specify the size of a class array ?

tuxduino:
Will the final executable contain only one instance of the MPLArrary<int, 10> code, or will there be code duplication ?

There will only ever be one instance of the executable code if that's what you mean. Each compilation unit gets its own copy of the template methods in the object code but they are marked with the .weak attribute which causes the linker to discard duplicates.