[Boost-users] copy constructor for derived boost::multi_array

Subject: [Boost-users] copy constructor for derived boost::multi_array
From: HweeKuan Lee (hweekuan_at_[hidden])
Date: 2009-08-24 21:46:20

i am having problems compiling class derived from boost::multi_array. the copy constructor does not compile. as i understand, the usual copy constructor for derived class can be implemented as in line 12 in the code below. however, can't do the same for boost::multi_array at line 21. lots of compile error, i extracted a small part of it below

  1 #include <boost/multi_array.hpp>
  2 
  3 // ------------------------------------------
  4 template<class V> struct base {
  5   base(int y)            : u(y  ) { }
  6   base(const base<V>& b) : u(b.u) { }
  7   int u;
  8 };
  9 
 10 template<class V> struct derived : public base<V> {
 11   derived(int y)               : base<V>(y) { }
 12   derived(const derived<V>& d) : base<V>(d) { }
 13 };
 14 // ------------------------------------------
 15 template<class V, unsigned int D>
 16 struct my_multi : public boost::multi_array<V,D> {
 17 
 18   template<class extent_type>
 19   my_multi(const extent_type&   e) : boost::multi_array<V,D>(e) { }
 20 
 21   my_multi(const my_multi<V,D>& t) : boost::multi_array<V,D>(t) { }
 22 };
 23 // ------------------------------------------
 24 int main () {
 25   derived<int> d(1.0);
 26   derived<int> e(d);     // ok
 27 
 28   my_multi<int,2> mm0(boost::extents[3][4]);
 29   mm0[0][0] = 6;     // ok
 30   my_multi<int,2> mm1(mm0);
 31 }

--------------
extracted compile error:

bmulti.C:21:   instantiated from 'my_multi<V, D>::my_multi(const my_multi<V, D>&) [with V = int, unsigned int D = 2u]'
bmulti.C:30:   instantiated from here
/opt/local/include/boost/multi_array/collection_concept.hpp:44: error: 'struct my_multi<int, 2u>' has no member named 'swap'

bmulti.C:21:   instantiated from 'my_multi<V, D>::my_multi(const my_multi<V, D>&) [with V = int, unsigned int D = 2u]'
bmulti.C:30:   instantiated from here
/opt/local/include/boost/multi_array/algorithm.hpp:56: error: cannot convert 'boost::detail::multi_array::const_sub_array<int, 1ul, const int*>' to 'long unsigned int' in assignment