Putting non-copied objects in std containers

Question

Is this class a standard C ++ 0x way to prevent copying and assignment to protect client code from being accidentally double deleted data?

struct DataHolder {
  int *data;   // dangerous resource
  DataHolder(const char* fn); // load from file or so
  DataHolder(const char* fn, size_t len); // *from answers: added*
  ~DataHolder() { delete[] data; }

  // prevent copy, to prevent double-deletion
  DataHolder(const DataHolder&) = delete;
  DataHolder& operator=(const DataHolder&) = delete;

  // enable stealing
  DataHolder(DataHolder &&other) {
    data=other.data; other.data=nullptr;
  }
  DataHolder& operator=(DataHolder &&other) {
    if(&other!=this) { data = other.data; other.data=nullptr};
    return *this;
  }
};

You noticed that I have defined new methods for moving and moving here. Did I implement them correctly?

Is there any way - using the definition of displacement and displacement - to put DataHolderin a standard container? like a vector? How should I do it?

Interestingly, some options come to mind:

// init-list. do they copy? or do they move?
// *from answers: compile-error, init-list is const, can nor move from there*
vector<DataHolder> abc { DataHolder("a"), DataHolder("b"), DataHolder("c") };

// pushing temp-objects.
vector<DataHolder> xyz;
xyz.push_back( DataHolder("x") );
// *from answers: emplace uses perfect argument forwarding*
xyz.emplace_back( "z", 1 );

// pushing a regular object, probably copies, right?
DataHolder y("y");
xyz.push_back( y ); // *from anwers: this copies, thus compile error.*

// pushing a regular object, explicit stealing?
xyz.push_back( move(y) );

// or is this what emplace is for?
xyz.emplace_back( y ); // *from answers: works, but nonsense here*

An idea emplace_backis just a guess.

Change . I used the answers in the sample code for reader convenience.

Answer 1

.

• const DataHolder &&other ( ).

• if(&other!=this) , .

• . DataHolder, .

• push_back emplace_back rvalue. , lvalue ( y), .

push_back emplace_back , . emplace_back - , DataHolder , , . :.

// Imagine this new constructor:
DataHolder(const char* fn, size_t len);

xyz.emplace_back( "data", 4 );  // ok
xyz.push_back("data", 4 );  // compile time error

Update:

, .

DataHolder& operator=(DataHolder &&other)
{
   if(&other!=this)
   {
      delete[] data;  // insert this
      data = other.data;
      other.data=nullptr;
   }
   return *this;
}

Answer 2

, , . DataHolder("a"), , . ++ 0x , , std::unique_ptr .
, :

  // enable stealing
  DataHolder(const DataHolder &&other) {
    data=other.data; other.data=nullptr;
  }
  DataHolder& operator=(const DataHolder&&other) {
    if(&other!=this) { data = other.data; other.data=nullptr};
    return *this;
  }

? other data, other . DataHolder&&.