hmm it could be container of any type (set, multiset, list, vector, array, deque). It should act like ruby on rails, flatten. http://www.ruby-doc.org/core/classes/Array.html#M002241 On 10/22/07, Vinzenz 'evilissimo' Feenstra wrote:

Oops, some typos here.

Vinzenz 'evilissimo' Feenstra schrieb:

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Hi,

I am wondering how your example container looks like, since it seems to contain several types.

If container is a container containing containers with values, you could do something like this:

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[code] vectorcontainer::value_type::value_type flattened; for(container::iterator it = c.begin(), end = c.end();beg != end; ++it) flattened(it->begin(), it->end(), std::back_inserter(flattened)); [/code] Should be: [code] std::vectorcontainer::value_type::value_type flattened; for(container::iterator it = c.begin(), end = c.end();beg != end; ++it) std::copy(it->begin(), it->end(), std::back_inserter(flattened)); [/code]

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Regards, Vinzenz

chun ping wang schrieb:

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Is their some kind of method to flatten a stl container...

example [[1, 4], [a,b, c], [b, [e]] ] becomes [1, 4, a, b, c, b, e]

Sorry for the mistake. Regards, Vinzenz

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Digvijoy Chatterjee wrote:

...and how do u intend to create a container that stores any container( set, multiset ,list, vector..... ) in C++ , if u really want stuff like Ruby ....take a look at boost::variant ( already known types of containers to store in a container ) , or boost::any ( unknown container types to be stored in a container )

HTH Digz

On 10/23/07, chun ping wang wrote:

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hmm it could be container of any type (set, multiset, list, vector, array, deque).

It should act like ruby on rails, flatten.

http://www.ruby-doc.org/core/classes/Array.html#M002241

If you are looking for a function to flatten any STL container [of STL containers [etc]], the code below will work. (It works under VS 2003.) It may need cleaning up, and incorrect usage may generate horrid error messages. There are some test functions at the end. David #include <vector> #include <deque> #include <list> #include <cassert> #include #include #include #include #include using namespace boost; using namespace boost::assign; using namespace std; template struct is_leaf_of_iterator { static const bool value = false; }; // Normal iterator template struct is_leaf_of_iterator >::type> { static const bool value = is_same< ContainerObject, iterator_traits<OutIt>::value_type >::value; }; // back iterator, front iterator, insert iterator(?) template struct is_leaf_of_iterator >::type> { static const bool value = is_same< ContainerObject, OutIt::container_type::value_type >::value; }; template struct do_flatten; // Call self again with sub-container until reach a leaf. // A leaf is defined as the type expected by the output iterator. template struct do_flatten { static void apply(const ContainerObject &c, OutIt &out) { for(ContainerObject::const_iterator it = c.begin() ; it != c.end() ; ++it) { do_flatten::value >::apply(*it, out); } } }; // partial specialization for non-containers template struct do_flatten { static void apply(const ContainerObject &c, OutIt &out) { *out = c; ++out; } }; template void flatten(const ContainerObject &c, OutIt &out) { static const bool isleaf = is_same::value; do_flatten::apply(c, out); } static std::vector<int> MakeV1_6() { std::vector<int> v; v += 1,2,3,4,5,6; // this uses boost::assign return v; } static void Test1() { typedef std::deque<int> deque_int; typedef std::vector< deque_int > vector_deque_ints; deque_int d1; d1 += 1,2,3; deque_int d2; d2 += 4,5,6; vector_deque_ints v; v += d1,d2; // [[1,2,3],[4,5,6]] std::vector<int> out; flatten(v, std::back_inserter(out)); assert(out == MakeV1_6()); } static void Test2() { typedef std::deque<int> d_i; typedef std::list l_d_i; typedef std::vector< l_d_i > v_l_d_i; d_i d1; d1 += 1,2; d_i d2; d2 += 3,4; d_i d3;d3 += 5,6; l_d_i l1; l1 += d1,d2; l_d_i l2; l2 += d3; v_l_d_i v; v += l1, l2; //[[[1,2],[3,4]],[[5,6]]] std::vector<int> out; flatten(v, std::back_inserter(out)); assert(out == MakeV1_6()); } int main() { std::vector<int> v; v.push_back(0); flatten(static_cast<int>(0), v.begin()); flatten(v, v.begin()); std::vector<double> d; //flatten(d, v.begin()); // fails: v.begin() wrong type for double Test1(); Test2(); }