public member function
<map>

std::map::get_allocator

allocator_type get_allocator() const;
allocator_type get_allocator() const noexcept;
Get allocator
Returns a copy of the allocator object associated with the map.

Parameters

none

Return Value

The allocator.

Member type allocator_type is the type of the allocator used by the container, defined in map as an alias of its fourth template parameter (Alloc).

Example

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// map::get_allocator
#include <iostream>
#include <map>

int main ()
{
  int psize;
  std::map<char,int> mymap;
  std::pair<const char,int>* p;

  // allocate an array of 5 elements using mymap's allocator:
  p=mymap.get_allocator().allocate(5);

  // assign some values to array
  psize = sizeof(std::map<char,int>::value_type)*5;

  std::cout << "The allocated array has a size of " << psize << " bytes.\n";

  mymap.get_allocator().deallocate(p,5);

  return 0;
}

The example shows an elaborate way to allocate memory for an array of pairs using the same allocator used by the container.
A possible output is:
The allocated array has a size of 40 bytes.

Complexity

Constant.

Iterator validity

No changes.

Data races

The container is accessed.
No contained elements are accessed: concurrently accessing or modifying them is safe.

Exception safety

No-throw guarantee: this member function never throws exceptions.
Copying any instantiation of the default allocator is also guaranteed to never throw.

See also

  • 9281021542 2018-02-20
  • 632231541 2018-02-20
  • 9751491540 2018-02-20
  • 8333621539 2018-02-20
  • 995001538 2018-02-20
  • 6477441537 2018-02-20
  • 511981536 2018-02-19
  • 2072881535 2018-02-19
  • 6024461534 2018-02-19
  • 7594061533 2018-02-19
  • 9311341532 2018-02-19
  • 4928331531 2018-02-19
  • 38561530 2018-02-19
  • 7776611529 2018-02-19
  • 3038041528 2018-02-19
  • 9566341527 2018-02-19
  • 3936031526 2018-02-19
  • 9531111525 2018-02-19
  • 291211524 2018-02-19
  • 8962001523 2018-02-19