Re: [boost] [fusion][ping] how to initialize a container of non-const references to objects, from a container of objects
Stjepan Rajko wrote:
Found a case where it doesn't compile - adapting your example to how ... However, if I change this to:
typedef fusion::vector<> vec; vec v; fusion::transform_view<vec, make_ref> t(v, make_ref()); fusion::vector<> vec_of_references(t); // does not compile
The problem is that since vec_of_references is a vector of size 0 then it can't initialize from the transform_view because vector0 has no constructors defined (so only copy constructible).
For sake of consistency, would it be possible to add a templated constructor to vector0 that could take a fusion sequence and do nothing with it? I'm using this from a templated class and it would be helpful if I didn't have to specially treat the size 0 case.
Vector, list and deque (experimental) all have converting ctors for the zero length case now.
Or, perhaps there is another simple solution I'm missing... :-)
No, I think your solution is simple and the right one, it definitely improves the uniformity of container behaviour in Fusion. Thanks for pointing this one out Cheers Dan ___________________________________________________________ Yahoo! Answers - Got a question? Someone out there knows the answer. Try it now. http://uk.answers.yahoo.com/
On 7/6/07, dan marsden <danmarsden@yahoo.co.uk> wrote:
Vector, list and deque (experimental) all have converting ctors for the zero length case now.
Thanks, much appreciated! Stjepan
dan marsden wrote:
Stjepan Rajko wrote:
Found a case where it doesn't compile - adapting your example to how ... However, if I change this to:
typedef fusion::vector<> vec; vec v; fusion::transform_view<vec, make_ref> t(v, make_ref()); fusion::vector<> vec_of_references(t); // does not compile
The problem is that since vec_of_references is a vector of size 0 then it can't initialize from the transform_view because vector0 has no constructors defined (so only copy constructible).
For sake of consistency, would it be possible to add a templated constructor to vector0 that could take a fusion sequence and do nothing with it? I'm using this from a templated class and it would be helpful if I didn't have to specially treat the size 0 case.
Vector, list and deque (experimental) all have converting ctors for the zero length case now.
Or, perhaps there is another simple solution I'm missing... :-)
No, I think your solution is simple and the right one, it definitely improves the uniformity of container behaviour in Fusion.
Thanks for pointing this one out
Hmm after updating I now can't #include <boost/fusion/sequence/container/vector.hpp> in my source code on RVCT. It complains with: boost/fusion/sequence/conversion/detail/as_vector.hpp", line 41: Error: #70: incomplete type is not allowed return vector<>(); ^ :( Any Ideas? Thanks, Michael Marcin
participants (3)
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dan marsden -
Michael Marcin -
Stjepan Rajko