Semantics: typedefs

The following types are implementation defined:

typedef ... value_type;
typedef ... reference;
typedef ... const_reference;
typedef ... pointer;
typedef ... const_pointer;

However, the structure of the type mimics std::pair s.t. one can use first and second members. The reference-types are not real references and the pointer-types are not real pointers. However, one may still write

map_type::value_type       a_value      = *m.begin();
a_value.second->foo();
map_type::reference        a_reference  = *m.begin();
a_reference.second->foo();
map_type::const_reference  a_creference = *const_begin(m);
map_type::pointer          a_pointer    = &*m.begin();
a_pointer->second->foo();
map_type::const_pointer    a_cpointer   = &*const_begin(m);

The difference compared to std::map<Key,T*> is that constness is propagated to the pointer (that is, to second) in const_itertor.

Semantics: modifiers

• std::pair<iterator,bool> insert( key_type& k, value_type x );

  • Requirements: x != 0
  • Effects: Takes ownership of x and insert it iff there is no equivalent of it already. The bool part of the return value indicates insertion and the iterator points to the element with key x.
  • Throws: bad_pointer if x == 0
  • Exception safety: Strong guarantee

• template< class U > std::pair<iterator,bool> insert( const key_type& k, compatible-smart-ptr<U> x );

  • Equivalent to (but without the const_cast): return insert( const_cast<key_type&>(k), x.release() );

Semantics: lookup

• T& operator[]( const key_type& key );

  • Effects: returns the object with key key if it exists; otherwise a new object is allocated and inserted and its reference returned.
  • Exception-safety: Strong guarantee

• T&       at( const key_type& key );

• const T& at( const key_type& jey ) const;

  • Requirement: the key exists
  • Throws: bad_ptr_container_operation if the key does not exist

Semantics: pointer container requirements

• bool transfer( iterator object, ptr_map_adapter& from );

  • Requirements: not from.empty()
  • Effects: Inserts the object defined by object into the container and remove it from from iff no equivalent object exists.
  • Returns: whether the object was transfered
  • Exception safety: Strong guarantee

• size_type transfer( iterator first, iterator last, ptr__set_adapter& from );

  • Requirements: not from.empty()
  • Effects: Inserts the objects defined by the range [first,last) into the container and remove it from from. An object is only transferred if no equivalent object exists.
  • Returns: the number of transfered objects
  • Exception safety: Basic guarantee

• template< class Range > void transfer( const Range& r, ptr_map_adapter& from );

  • Effects: return transfer( boost::begin(r), boost::end(r), from );

• size_type transfer( ptr_set_adapter& from );

  • Effects: return transfer( from.begin(), from.end(), from );.