2009/3/8 Steven Watanabe <watanabesj@gmail.com>:
AMDG
Joachim Faulhaber wrote:
I think that the assumption of Vicente ...
dynamic_bitset<> bs1, bs2; // ... expecting ... intersetcs(bs1, bs2)?
is kind of justified, because function intersects could be implemented not only by memberfunctions of dynamic_bitset but even with non member functions, in more than one way,
e.g. bool intersects(const dynamic_bitset<Block, Allocator>& a, const dynamic_bitset<Block, Allocator>& b) // nonmembers & and member empty() { return !(a & b).empty(); }
this would be consistent with the coding standard to keep class interfaces minimal and to implement namespace global functions on the bases of class memberfunctions where ever this is possible.
This would be less efficient because of the temporary.
Thank you both (this also refers to Vicente since he had the same argument). Yes, but this is not the only way to implement the function. I think this implementation is as efficient as the member function: template <typename Block, typename Allocator> bool intersects(const dynamic_bitset<Block, Allocator>& a, const dynamic_bitset<Block, Allocator>& b) { typedef typename dynamic_bitset<Block, Allocator>::size_type size_type; size_type common_blocks = a.num_blocks() < b.num_blocks() ? a.num_blocks() : b.num_blocks(); for(size_type i = 0; i < common_blocks; ++i) { if(a.test(i) & b.test(i)) return true; } return false; } best regards, Joachim