Re: assigning vector with predefined values

On Apr 27, 5:30 am, meisterbartsch <Bluesman.Patr...@gmx.de> wrote:


You can use a helper class with method chaining (http://
www.parashift.com/c++-faq-lite/references.html#faq-8.4) like this (not
tested):

 #include <vector>
 using namespace std;

 template<typename T>
 class Initializer
 {
   vector<T> v_;
 public:
   Initializer( const size_t capacity=0 )
   {
     v_.reserve( capacity );
   }

   Initializer& Add( const T& t )
   {
     v_.push_back( t );
     return *this;
   }

   operator vector<T>() const
   {
     return v_;
   }
 };

 int main()
 {
   const vector<double> v = Initializer<double>( 4 )
     .Add(1.0)
     .Add(2.0)
     .Add(3.0)
     .Add(4.0);
 }

There's a vector copy in there, but any modern compiler will use the
return value optimization to get rid of it.

Cheers! --M